Status signals: Adaptive benefits of displaying and observing the nonverbal expressions of pride and shame
Jason P Martens et al.; 2012
http://sharifflab.com/wp-content/uploads/downloads/2012/04/martenstracyshariffi2012.pdf
Abstract
A growing body of research suggests that pride and shame are associated with distinct, crossculturally recognised nonverbal expressions, which are spontaneously displayed in situations of success and failure, respectively. Here, we review these findings, then offer a theoretical account of the adaptive benefits of these displays. We argue that both pride and shame expressions function as social signals that benefit both observers and expressers. Specifically, pride displays function to signal high status, which benefits displayers by according them deference from others, and benefits observers by affording them valuable information about social-learning opportunities. Shame displays function to appease others after a social transgression, which benefits displayers by allowing them to avoid punishment and negative appraisals, and observers by easing their identification of committed group members and followers.
Sonntag, 31. März 2013
The Great Struggles of Life- Darwin and the Emergence of Evolutionary Psychology
The Great Struggles of Life - Darwin and the Emergence of Evolutionary Psychology
David M Buss; 2009
http://www.homepage.psy.utexas.edu/homepage/group/busslab/pdffiles/great%20struggles%20of%20life%20-%202009AmerPsych.pdf
Abstract
---------------------------------
David M Buss; 2009
http://www.homepage.psy.utexas.edu/homepage/group/busslab/pdffiles/great%20struggles%20of%20life%20-%202009AmerPsych.pdf
Abstract
Darwin envisioned a scientific revolution for psychology. His theories of natural and sexual selection identified two classes of struggles—the struggle for existence and the struggle for mates. The emergence of evolutionary psychology and related disciplines signals the ful-fillment of Darwin’s vision. Natural selection theory guides scientists to discover adaptations for survival. Sexual selection theory illuminates the sexual struggle, highlighting mate choice and same-sex competition adaptations. Theoretical developments since publication of On the Origin of Species identify important struggles unknown to Darwin, notably, within-families conflicts and conflict between the sexes. Evolutionary psychology synthesizes modern evolutionary biology and psychology to penetrate some of life’s deep mysteries: Why do many struggles center around sex? Why is social conflict pervasive? And what are the mechanisms of mind that define human nature?
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"This article traces Darwin’s influence on evolutionary psychology and outlines the field’s development beyond Darwin’s vision."
Male satin bowerbird problem-solving ability predicts mating success
Male satin bowerbird problem-solving ability predicts mating success
Jason Keagy et al.; 2009
http://www.life.umd.edu/biology/borgialab/Keagy_et_al_2009_print.pdf
Abstract
Mate choice and mate attraction are important behaviours influencing the evolution of elaborate traits. It is possible that male general cognitive performance plays an important role in sexual attractiveness, but there has been no direct test of this hypothesis. Satin bowerbirds, Ptilonorhynchus violaceus, are an excellent species for testing this hypothesis because their complex male courtship, including use of decorations of certain colours, suggests a selective advantage to individuals with superior cognitive abilities. We used males’ strong aversion to red objects on their bowers to design two unique problemsolving tests. We presented males with these problems to test the hypothesis that males that are better problem-solvers have higher mating success. We confirmed this prediction and demonstrate that neither age nor motivational level significantly influenced problem-solving scores. Our findings suggest that general cognitive performance is related to male mating success. This is the first evidence that individuals with better problem-solving abilities are more sexually attractive.
[see also: Cognitive ability and the evolution of multiple behavioral display traits; 2012 http://beheco.oxfordjournals.org/content/23/2/448.full.pdf?keytype=ref&ijkey=CHbVqN1Rxssz8d4]
Jason Keagy et al.; 2009
http://www.life.umd.edu/biology/borgialab/Keagy_et_al_2009_print.pdf
Abstract
Mate choice and mate attraction are important behaviours influencing the evolution of elaborate traits. It is possible that male general cognitive performance plays an important role in sexual attractiveness, but there has been no direct test of this hypothesis. Satin bowerbirds, Ptilonorhynchus violaceus, are an excellent species for testing this hypothesis because their complex male courtship, including use of decorations of certain colours, suggests a selective advantage to individuals with superior cognitive abilities. We used males’ strong aversion to red objects on their bowers to design two unique problemsolving tests. We presented males with these problems to test the hypothesis that males that are better problem-solvers have higher mating success. We confirmed this prediction and demonstrate that neither age nor motivational level significantly influenced problem-solving scores. Our findings suggest that general cognitive performance is related to male mating success. This is the first evidence that individuals with better problem-solving abilities are more sexually attractive.
[see also: Cognitive ability and the evolution of multiple behavioral display traits; 2012 http://beheco.oxfordjournals.org/content/23/2/448.full.pdf?keytype=ref&ijkey=CHbVqN1Rxssz8d4]
Men with elevated testosterone levels show more affiliative behaviours during interactions with women
Men with elevated testosterone levels show more affiliative behaviours during interactions with women
Leander van der Meij et al; 2012
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3223653/
Abstract
Testosterone (T) is thought to play a key role in male–male competition and courtship in many vertebrates, but its precise effects are unclear. We explored whether courtship behaviour in humans is modulated and preceded by changes in T. Pairs of healthy male students first competed in a non-physical contest in which their T levels became elevated. Each participant then had a short, informal interaction with either an unfamiliar man or woman. The sex of the stimulus person did not affect the participants' behaviour overall. However, in interactions with women, those men who had experienced a greater T increase during the contest subsequently showed more interest in the woman, engaged in more self-presentation, smiled more and made more eye contact. No such effects were seen in interactions with other men. This is the first study to provide direct evidence that elevating T during male–male competition is followed by increased affiliative behaviour towards women.
Leander van der Meij et al; 2012
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3223653/
Abstract
Testosterone (T) is thought to play a key role in male–male competition and courtship in many vertebrates, but its precise effects are unclear. We explored whether courtship behaviour in humans is modulated and preceded by changes in T. Pairs of healthy male students first competed in a non-physical contest in which their T levels became elevated. Each participant then had a short, informal interaction with either an unfamiliar man or woman. The sex of the stimulus person did not affect the participants' behaviour overall. However, in interactions with women, those men who had experienced a greater T increase during the contest subsequently showed more interest in the woman, engaged in more self-presentation, smiled more and made more eye contact. No such effects were seen in interactions with other men. This is the first study to provide direct evidence that elevating T during male–male competition is followed by increased affiliative behaviour towards women.
Intrasexual competition among women: Vocal femininity affects perceptions of attractiveness and flirtatiousness
Intrasexual competition among women: Vocal femininity affects perceptions of attractiveness and flirtatiousness
David A Puts et al.; 2011
http://www.wellingresearchlab.com/uploads/1/3/5/7/13572010/puts_et_al_2011_paid.pdf
Abstract
Cognitive mechanisms for recognizing high quality sexual rivals should facilitate the economical allocation of mating effort. Women compete to attract male investment, and previous studies have shown that feminine voices are attractive to men. Here, we manipulated two sexually dimorphic acoustic parameters in women’s voices, fundamental frequency and formant dispersion, by the same perceptual amounts and explored the effects on attractiveness to heterosexual men in short- and long-term mating contexts. Femininity in both acoustic parameters was more attractive to men, especially in short-term mating contexts, and formant dispersion had a larger effect than did fundamental frequency. We then explored the effects of these manipulations on women’s perceptions of other women’s flirtatiousness and attractiveness to men. Feminine voices were perceived as more flirtatious and more attractive to men, and women were most sensitive to formant dispersion, the acoustic parameter that had the stronger effect on men’s preferences. These results support the interpretation that women use vocal femininity to track the threat potential of competitors.
David A Puts et al.; 2011
http://www.wellingresearchlab.com/uploads/1/3/5/7/13572010/puts_et_al_2011_paid.pdf
Abstract
Cognitive mechanisms for recognizing high quality sexual rivals should facilitate the economical allocation of mating effort. Women compete to attract male investment, and previous studies have shown that feminine voices are attractive to men. Here, we manipulated two sexually dimorphic acoustic parameters in women’s voices, fundamental frequency and formant dispersion, by the same perceptual amounts and explored the effects on attractiveness to heterosexual men in short- and long-term mating contexts. Femininity in both acoustic parameters was more attractive to men, especially in short-term mating contexts, and formant dispersion had a larger effect than did fundamental frequency. We then explored the effects of these manipulations on women’s perceptions of other women’s flirtatiousness and attractiveness to men. Feminine voices were perceived as more flirtatious and more attractive to men, and women were most sensitive to formant dispersion, the acoustic parameter that had the stronger effect on men’s preferences. These results support the interpretation that women use vocal femininity to track the threat potential of competitors.
Beauty and the beast: mechanisms of sexual selection in humans
Beauty and the beast: mechanisms of sexual selection in humans
David A Puts; 2010
http://dieoff.com/_Biology/BeautyAndTheBeast.pdf
Abstract
Literature in evolutionary psychology suggests that mate choice has been the primary mechanism of sexual selection in humans, but this conclusion conforms neither to theoretical predictions nor available evidence. Contests override other mechanisms of sexual selection; that is, when individuals can exclude their competitors by force or threat of force, mate choice, sperm competition, and other mechanisms are impossible. Mates are easier to monopolize in two dimensional mating environments, such as land, than in three-dimensional environments, such as air, water, and trees. Thus, two-dimensional mating environments may tend to favor the evolution of contests. The twodimensionality of the human mating environment, along with phylogeny, the spatial and temporal clustering of mates and competitors, and anatomical considerations, predict that contest competition should have been the primary mechanism of sexual selection in men. A functional analysis supports this prediction. Men's traits are better designed for contest competition than for other sexual selection mechanisms; size, muscularity, strength, aggression, and the manufacture and use of weapons probably helped ancestral males win contests directly, and deep voices and facial hair signal dominance more effectively than they increase attractiveness. However, male monopolization of females was imperfect, and female mate choice, sperm competition, and sexual coercion also likely shaped men's traits. In contrast, male mate choice was probably central in women's mating competition because ancestral females could not constrain the choices of larger and more aggressive males through force, and attractive women could obtain greater male investment. Neotenous female features and body fat deposition on the breasts and hips appear to have been shaped by male mate choice.
David A Puts; 2010
http://dieoff.com/_Biology/BeautyAndTheBeast.pdf
Abstract
Literature in evolutionary psychology suggests that mate choice has been the primary mechanism of sexual selection in humans, but this conclusion conforms neither to theoretical predictions nor available evidence. Contests override other mechanisms of sexual selection; that is, when individuals can exclude their competitors by force or threat of force, mate choice, sperm competition, and other mechanisms are impossible. Mates are easier to monopolize in two dimensional mating environments, such as land, than in three-dimensional environments, such as air, water, and trees. Thus, two-dimensional mating environments may tend to favor the evolution of contests. The twodimensionality of the human mating environment, along with phylogeny, the spatial and temporal clustering of mates and competitors, and anatomical considerations, predict that contest competition should have been the primary mechanism of sexual selection in men. A functional analysis supports this prediction. Men's traits are better designed for contest competition than for other sexual selection mechanisms; size, muscularity, strength, aggression, and the manufacture and use of weapons probably helped ancestral males win contests directly, and deep voices and facial hair signal dominance more effectively than they increase attractiveness. However, male monopolization of females was imperfect, and female mate choice, sperm competition, and sexual coercion also likely shaped men's traits. In contrast, male mate choice was probably central in women's mating competition because ancestral females could not constrain the choices of larger and more aggressive males through force, and attractive women could obtain greater male investment. Neotenous female features and body fat deposition on the breasts and hips appear to have been shaped by male mate choice.
Freitag, 29. März 2013
Sex Differences in Mathematics and Reading Achievement Are Inversely Related
Sex Differences in Mathematics and Reading Achievement Are Inversely Related: Within- and Across-Nation Assessment of 10 Years of PISA Data
Gijsbert Stoet and David C Geary; 2013
Abstract
We analyzed one decade of data collected by the Programme for International Student Assessment (PISA), including the mathematics and reading performance of nearly 1.5 million 15 year olds in 75 countries. Across nations, boys scored higher than girls in mathematics, but lower than girls in reading. The sex difference in reading was three times as large as in mathematics. There was considerable variation in the extent of the sex differences between nations. There are countries without a sex difference in mathematics performance, and in some countries girls scored higher than boys. Boys scored lower in reading in all nations in all four PISA assessments (2000, 2003, 2006, 2009). Contrary to several previous studies, we found no evidence that the sex differences were related to nations’ gender equality indicators. Further, paradoxically, sex differences in mathematics were consistently and strongly inversely correlated with sex differences in reading: Countries with a smaller sex difference in mathematics had a larger sex difference in reading and vice versa. We demonstrate that this was not merely a between-nation, but also a within-nation effect. This effect is related to relative changes in these sex differences across the performance continuum: We did not find a sex difference in mathematics among the lowest performing students, but this is where the sex difference in reading was largest. In contrast, the sex difference in mathematics was largest among the higher performing students, and this is where the sex difference in reading was smallest. The implication is that if policy makers decide that changes in these sex differences are desired, different approaches will be needed to achieve this for reading and mathematics. Interventions that focus on high-achieving girls in mathematics and on low achieving boys in reading are likely to yield the strongest educational benefits.
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" In summary, there are two distinct sex differences in scholastic performance that affect very different segments of the population. On the one hand, boys score lower in reading, in particular at the low end of the reading performance continuum. On the other hand, girls score lower in mathematics at the high end of the mathematics performance continuum. It is important to realize that the latter phenomenon continues to exist, despite the educational gains of women in economically developed countries, and the increased participation of women in higher education in general can easily give the false impression that we are getting closer to the end of the sex difference in mathematics."
Same or Different? Clarifying the Relationship of Need for Cognition to Personality and Intelligence
Same or Different? Clarifying the Relationship of Need for Cognition to Personality and Intelligence
Monika Fleischhauer et al., 2010
Abstract
Need for cognition (NFC) refers to an individual’s tendency to engage in and enjoy effortful cognitive processing. So far, little attention has been paid to a systematic evaluation of the distinctiveness of NFC from traits with similar conceptualization and from intelligence. The present research contributes to filling this gap by examining the relation of NFC to well-established personality concepts (Study 1) and to a comprehensive measure of intelligence in a sample with broad educational backgrounds (Study 2). We observed NFC to be positively correlated with openness, emotional stability, and traits indicating goal orientation. Using confirmatory factor analysis and event-related potentials, incremental validity of NFC and openness to ideas was demonstrated, showing that NFC is more predictive of drive-related and goal-oriented behavior and attentional resource allocation. Regarding intelligence, NFC was more associated with fluid than with crystallized aspects of intelligence. Altogether, the results provide strong support for the conceptual autonomy of NFC.
Monika Fleischhauer et al., 2010
Abstract
Need for cognition (NFC) refers to an individual’s tendency to engage in and enjoy effortful cognitive processing. So far, little attention has been paid to a systematic evaluation of the distinctiveness of NFC from traits with similar conceptualization and from intelligence. The present research contributes to filling this gap by examining the relation of NFC to well-established personality concepts (Study 1) and to a comprehensive measure of intelligence in a sample with broad educational backgrounds (Study 2). We observed NFC to be positively correlated with openness, emotional stability, and traits indicating goal orientation. Using confirmatory factor analysis and event-related potentials, incremental validity of NFC and openness to ideas was demonstrated, showing that NFC is more predictive of drive-related and goal-oriented behavior and attentional resource allocation. Regarding intelligence, NFC was more associated with fluid than with crystallized aspects of intelligence. Altogether, the results provide strong support for the conceptual autonomy of NFC.
Donnerstag, 28. März 2013
Sexual Selection on Human Faces and Voices
Sexual Selection on Human Faces and Voices
David A Puts et al., 2012
http://www.putslab.psu.edu/pdfs/Puts%20et%20al%20J%20Sex%20Res%202012-1.pdf
Abstract
Humans are highly sexually dimorphic primates, and some of the most conspicuous human sex differences occur in the face and voice. Consequently, this article utilizes research findings on human faces and voices to illustrate how human sex differences may have arisen by sexual selection (i.e., the type of natural selection favoring traits that increase mating opportunities). Evidence suggesting that sexual selection shaped women’s faces and voices is reviewed. However, sexual selection likely operated more strongly on men over human evolution. Thus, this research focuses on two types of sexual selection operating on men: female mate choice, which favors traits that attract females, and male contests, which favor traits for excluding competitors from mates by force or threat of force. This article demonstrates how masculine faces and voices advertize critical information about men’s mate value and threat potential, and reviews evidence that women’s preferences and men’s deference to masculine faces and voices reflect this information content. Data suggesting that facial and vocal masculinity influences men’s mating opportunities and reproduction are discussed, and the article concludes by highlighting directions for future research.
David A Puts et al., 2012
http://www.putslab.psu.edu/pdfs/Puts%20et%20al%20J%20Sex%20Res%202012-1.pdf
Abstract
Humans are highly sexually dimorphic primates, and some of the most conspicuous human sex differences occur in the face and voice. Consequently, this article utilizes research findings on human faces and voices to illustrate how human sex differences may have arisen by sexual selection (i.e., the type of natural selection favoring traits that increase mating opportunities). Evidence suggesting that sexual selection shaped women’s faces and voices is reviewed. However, sexual selection likely operated more strongly on men over human evolution. Thus, this research focuses on two types of sexual selection operating on men: female mate choice, which favors traits that attract females, and male contests, which favor traits for excluding competitors from mates by force or threat of force. This article demonstrates how masculine faces and voices advertize critical information about men’s mate value and threat potential, and reviews evidence that women’s preferences and men’s deference to masculine faces and voices reflect this information content. Data suggesting that facial and vocal masculinity influences men’s mating opportunities and reproduction are discussed, and the article concludes by highlighting directions for future research.
Association Between Television, Movie, and Video Game Exposure and School Performance
Association Between Television, Movie, and Video Game Exposure and School Performance
Iman Sharif and James D Sargent
http://www.pediatricsdigest.mobi/content/118/4/e1061.full
Abstract
Iman Sharif and James D Sargent
http://www.pediatricsdigest.mobi/content/118/4/e1061.full
Abstract
BACKGROUND:
The relationship between media exposure and school performance has not been studied extensively in adolescents.
OBJECTIVE:
The purpose of this work was to test the relative effects of television, movie, and video game screen time and content on adolescent school performance.
METHODS:
We conducted a population-based cross-sectional survey of middle school students (grades 5–8) in the Northeastern United States. We looked at weekday television and video game screen time, weekend television and video game screen time, cable movie channel availability, parental R-rated movie restriction, and television content restriction. The main outcome was self-report of school performance (excellent, good, average, or below average). We used ordinal logistic-regression analysis to test the independent effects of each variable, adjusting for demographics, child personality, and parenting style.
RESULTS:
There were 4508 students who participated in the study; gender was equally represented, and 95% were white. In multivariate analyses, after adjusting for other covariates, the odds of poorer school performance increased with increasing weekday television screen time and cable movie channel availability and decreased with parental restriction of television content restriction. As compared with children whose parents never allowed them to watch R-rated movies, children who watched R-rated movies once in a while, sometimes, or all of the time had significantly increased cumulative odds of poorer school performance. Weekend screen time and video game use were not associated with school performance.
CONCLUSIONS:
We found that both content exposure and screen time had independent detrimental associations with school performance. These findings support parental enforcement of American Academy of Pediatrics guidelines for media time (particularly weekdays) and content limits to enhance school success.
Cognitive ability and health-related behaviors during adolescence: A prospective study across five years
Cognitive ability and health-related behaviors during adolescence: A prospective study across five years
Joseph Ciarrochi et al., 2012
Abstract
Longitudinal research on the links between intelligence and health behaviors among adolescents is rare. We report longitudinal data in which we assessed the relationships between intelligence as assessed in Grade 7 and consequential health outcomes in Grade 11. The mean age of respondents (N= 420; 188 males, 232 females) was 12.30 years (SD= 0.49) in Grade 7and 16.17 years (SD= 0.45) in Grade 11. They completed standardized verbal and numerical ability tests and a measure of conscientiousness in Grade 7 and health related questions in Grade 11. Results indicated that higher intelligence was associated with a number of healthy behaviors including delay in onset of cigarette smoking. Intelligence significantly predicted less time spent watching TV, lower physical exercise, and lower consumption of stimulant drinks. Covariate analyses showed that general intelligence predicted health outcomes after controlling for conscientiousness, socio-economic status, and gender.
Joseph Ciarrochi et al., 2012
Abstract
Longitudinal research on the links between intelligence and health behaviors among adolescents is rare. We report longitudinal data in which we assessed the relationships between intelligence as assessed in Grade 7 and consequential health outcomes in Grade 11. The mean age of respondents (N= 420; 188 males, 232 females) was 12.30 years (SD= 0.49) in Grade 7and 16.17 years (SD= 0.45) in Grade 11. They completed standardized verbal and numerical ability tests and a measure of conscientiousness in Grade 7 and health related questions in Grade 11. Results indicated that higher intelligence was associated with a number of healthy behaviors including delay in onset of cigarette smoking. Intelligence significantly predicted less time spent watching TV, lower physical exercise, and lower consumption of stimulant drinks. Covariate analyses showed that general intelligence predicted health outcomes after controlling for conscientiousness, socio-economic status, and gender.
Mittwoch, 27. März 2013
Sex Differences in Variability in Personality:
Sex Differences in Variability in Personality: A Study in Four Samples
Peter Borkenau et al., 2013
http://psych.ut.ee/~jyri/en/Borkenau-sex-differences-in-variability_JP2013.pdf
Abstract
Objective:
Men vary more than women in cognitive abilities and physical attributes, and we expected that men would vary more in personality too. That this has not been found previously may reflect that (a) personality was measured by self-reports that confound target sex with informant sex, and (b) men actually vary more but accentuate personality differences less than women.
Method:
We analyzed informant reports and self-reports on the NEO Personality Inventory ( NEO PI -R or NEO PI -3) collected for two community and two student samples from four countries: Czech Republic ( N = 714; age M= 36.1, SD = 14.1; 58% women), Estonia ( N = 1,685; age M= 42.6, SD = 13.4; 58% women), Belgium ( N = 345; age M= 18.4, SD = 3.0; 78% women), and Germany ( N = 302; age M= 23.4, SD = 2.7; 56% women).
Results:
Higher male than female variability was found in each sample for informant reports of Extraversion, Openness to Experience, Agreeableness, and Conscientiousness. Men but not women were overrepresented in both tails of the distributions of several personality traits.
Conclusions:
According to liability-threshold models of mental disorders, this may contribute to men ’s overrepresentation in some kinds of deviant groups.
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"The present study shows that although higher variability between men than between women is not found in self-reports of personality, informant reports vary significantly more for male than for female targets. That was found for all traits except Neuroticism, and it was found in each of the four samples."
Peter Borkenau et al., 2013
http://psych.ut.ee/~jyri/en/Borkenau-sex-differences-in-variability_JP2013.pdf
Abstract
Objective:
Men vary more than women in cognitive abilities and physical attributes, and we expected that men would vary more in personality too. That this has not been found previously may reflect that (a) personality was measured by self-reports that confound target sex with informant sex, and (b) men actually vary more but accentuate personality differences less than women.
Method:
We analyzed informant reports and self-reports on the NEO Personality Inventory ( NEO PI -R or NEO PI -3) collected for two community and two student samples from four countries: Czech Republic ( N = 714; age M= 36.1, SD = 14.1; 58% women), Estonia ( N = 1,685; age M= 42.6, SD = 13.4; 58% women), Belgium ( N = 345; age M= 18.4, SD = 3.0; 78% women), and Germany ( N = 302; age M= 23.4, SD = 2.7; 56% women).
Results:
Higher male than female variability was found in each sample for informant reports of Extraversion, Openness to Experience, Agreeableness, and Conscientiousness. Men but not women were overrepresented in both tails of the distributions of several personality traits.
Conclusions:
According to liability-threshold models of mental disorders, this may contribute to men ’s overrepresentation in some kinds of deviant groups.
------------------------------
"The present study shows that although higher variability between men than between women is not found in self-reports of personality, informant reports vary significantly more for male than for female targets. That was found for all traits except Neuroticism, and it was found in each of the four samples."
Short-term storage and mental speed account for the relationship between working memory and fluid intelligence
Short-term storage and mental speed account for the relationship between working memory and fluid intelligence
Burgaleta M and Colom R ; 2008
Abstract
Here, we explore the role of short-term storage, mental speed, processing efficiency, and controlled attention to account for the relationship between working memory and fluid intelligence. Ninety-six secondary school students were assessed by several tests and tasks to tap these psychological constructs. Specifically, each construct was measured by two tests or tasks from different content domains (verbal-numerical and spatial). The findings show that short-term storage and, to a lesser degree, mental speed, account for the relationship between working memory and fluid intelligence. Further, processing efficiency and controlled attention do not play a significant role.
Burgaleta M and Colom R ; 2008
Abstract
Here, we explore the role of short-term storage, mental speed, processing efficiency, and controlled attention to account for the relationship between working memory and fluid intelligence. Ninety-six secondary school students were assessed by several tests and tasks to tap these psychological constructs. Specifically, each construct was measured by two tests or tasks from different content domains (verbal-numerical and spatial). The findings show that short-term storage and, to a lesser degree, mental speed, account for the relationship between working memory and fluid intelligence. Further, processing efficiency and controlled attention do not play a significant role.
Sonntag, 24. März 2013
Are pro-social or socially aversive people more physically symmetrical? Symmetry in relation to over 200 personality variables
Are pro-social or socially aversive people more physically symmetrical? Symmetry in relation to over 200 personality variables
Nicholas S Holtzman et al., 2011
http://nickholtzman.com/Holtzman%20Augustine%20Senne%202011%20Are%20pro-social%20or%20socially%20aversive%20people%20more%20physically%20symmetrical%20Symmetry%20in%20relation%20to%20over%20200%20personality%20variables.pdf
Abstract
Symmetry on bilateral body parts indicates evolutionary fitness. Thus, traits positively associated with symmetry are thought to have conferred fitness in evolutionary history. Studies of the relationships between personality traits and symmetry have been narrow and have produced inconsistent findings. In our study, we relate both body symmetry and facial symmetry to 203 personality variables and to the Big Five. Our results demonstrate that (a) symmetry is related to personality traits beyond chance, (b) socially aversive traits, such as aggression and Neuroticism are positively related to symmetry, and (c) pro-social traits such as empathy and Agreeableness are negatively related to symmetry. Such trait levels may developmentally adjust in response to symmetry or may be inherited with symmetry (i.e., dual inheritance).
Nicholas S Holtzman et al., 2011
http://nickholtzman.com/Holtzman%20Augustine%20Senne%202011%20Are%20pro-social%20or%20socially%20aversive%20people%20more%20physically%20symmetrical%20Symmetry%20in%20relation%20to%20over%20200%20personality%20variables.pdf
Abstract
Symmetry on bilateral body parts indicates evolutionary fitness. Thus, traits positively associated with symmetry are thought to have conferred fitness in evolutionary history. Studies of the relationships between personality traits and symmetry have been narrow and have produced inconsistent findings. In our study, we relate both body symmetry and facial symmetry to 203 personality variables and to the Big Five. Our results demonstrate that (a) symmetry is related to personality traits beyond chance, (b) socially aversive traits, such as aggression and Neuroticism are positively related to symmetry, and (c) pro-social traits such as empathy and Agreeableness are negatively related to symmetry. Such trait levels may developmentally adjust in response to symmetry or may be inherited with symmetry (i.e., dual inheritance).
Fluid Intelligence and Psychosocial Adaptation
Fluid Intelligence and Psychosocial Outcome: From Logical Problem Solving to Social Adaptation
David Huepe et al.; 2011
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3177863/
Abstract
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David Huepe et al.; 2011
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3177863/
Abstract
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Background
While fluid intelligence has proved to be central to executive functioning, logical reasoning and other frontal functions, the role of this ability in psychosocial adaptation has not been well characterized.
Methodology/Principal Findings
A random-probabilistic sample of 2370 secondary school students completed measures of fluid intelligence (Raven's Progressive Matrices, RPM) and several measures of psychological adaptation: bullying (Delaware Bullying Questionnaire), domestic abuse of adolescents (Conflict Tactic Scale), drug intake (ONUDD), self-esteem (Rosenberg's Self Esteem Scale) and the Perceived Mental Health Scale (Spanish adaptation).
Lower fluid intelligence scores were associated with physical violence, both in the role of victim and victimizer. Drug intake, especially cannabis, cocaine and inhalants and lower self-esteem were also associated with lower fluid intelligence. Finally, scores on the perceived mental health assessment were better when fluid intelligence scores were higher.
Conclusions/Significance
Our results show evidence of a strong association between psychosocial adaptation and fluid intelligence, suggesting that the latter is not only central to executive functioning but also forms part of a more general capacity for adaptation to social contexts.
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A Self-Regulatory Model of Behavioral Disinhibition in Late Adolescence: Integrating Personality Traits, Externalizing Psychopathology, and Cognitive Capacity
A Self-Regulatory Model of Behavioral Disinhibition in Late Adolescence: Integrating Personality Traits, Externalizing Psychopathology, and Cognitive Capacity
Tim Bogg and Peter R Finn; 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3145208/
Abstract
Two samples with heterogeneous prevalence of externalizing psychopathology were used to investigate the structure of self-regulatory models of behavioral disinhibition and cognitive capacity. Consistent with expectations, structural equation modeling in the first sample (N = 541) showed a hierarchical model with three lower-order factors of impulsive sensation-seeking, anti-sociality/unconventionality, and lifetime externalizing problem counts, with a behavioral disinhibition superfactor best accounted for the pattern of covariation among six disinhibited personality trait indicators and four externalizing problem indicators. The structure was replicated in a second sample (N = 463) and showed that the behavioral disinhibition superfactor, and not the lower-order impulsive sensation-seeking, anti-sociality/unconventionality, and externalizing problem factors, was associated with lower IQ, reduced short-term memory capacity, and reduced working memory capacity. The results provide a systemic and meaningful integration of major self-regulatory influences during a developmentally important stage of life.
Tim Bogg and Peter R Finn; 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3145208/
Abstract
Two samples with heterogeneous prevalence of externalizing psychopathology were used to investigate the structure of self-regulatory models of behavioral disinhibition and cognitive capacity. Consistent with expectations, structural equation modeling in the first sample (N = 541) showed a hierarchical model with three lower-order factors of impulsive sensation-seeking, anti-sociality/unconventionality, and lifetime externalizing problem counts, with a behavioral disinhibition superfactor best accounted for the pattern of covariation among six disinhibited personality trait indicators and four externalizing problem indicators. The structure was replicated in a second sample (N = 463) and showed that the behavioral disinhibition superfactor, and not the lower-order impulsive sensation-seeking, anti-sociality/unconventionality, and externalizing problem factors, was associated with lower IQ, reduced short-term memory capacity, and reduced working memory capacity. The results provide a systemic and meaningful integration of major self-regulatory influences during a developmentally important stage of life.
Placing intelligence into an evolutionary framework or how g fits into the r–K matrix of life-history traits including longevity
Placing intelligence into an evolutionary framework or how g fits into the r–K matrix of life-history traits including longevity
J P Rushton; 2004
http://psychology.uwo.ca/faculty/rushtonpdfs/INTEL2004r-KLifeHistories.pdf
Abstract
First, I describe why intelligence (Spearman’s g) can only be fully understood through r–K theory, which places it into an evolutionary framework along with brain size, longevity, maturation speed, and several other life-history traits. The r–K formulation explains why IQ predicts longevity and also why the gap in mortality rates between rich and poor has increased with greater access to health care. Next, I illustrate the power of this approach by analyzing a large data set of life-history variables on 234 mammalian species and find that brain size correlates r=.70 with longevity (.59, after controlling for body weight and body length). A principal component analysis reveals a single r–K life-history factor with loadings such as: brain weight (.85), longevity (.91), gestation time (.86), birth weight (.62), litter size ( .54), age at first mating (.73), duration of lactation (.67), body weight (.61), and body length (.63). The factor loadings remain high when body weight and length are covaried. Finally, I demonstrate the theoretical importance of this approach in restoring the concept of bprogressQ to its proper place in evolutionary biology showing why, over the last 575 million years of evolutionary competition of finding and filling new niches, there has always been (and likely always will be) broom at the top.
J P Rushton; 2004
http://psychology.uwo.ca/faculty/rushtonpdfs/INTEL2004r-KLifeHistories.pdf
Abstract
First, I describe why intelligence (Spearman’s g) can only be fully understood through r–K theory, which places it into an evolutionary framework along with brain size, longevity, maturation speed, and several other life-history traits. The r–K formulation explains why IQ predicts longevity and also why the gap in mortality rates between rich and poor has increased with greater access to health care. Next, I illustrate the power of this approach by analyzing a large data set of life-history variables on 234 mammalian species and find that brain size correlates r=.70 with longevity (.59, after controlling for body weight and body length). A principal component analysis reveals a single r–K life-history factor with loadings such as: brain weight (.85), longevity (.91), gestation time (.86), birth weight (.62), litter size ( .54), age at first mating (.73), duration of lactation (.67), body weight (.61), and body length (.63). The factor loadings remain high when body weight and length are covaried. Finally, I demonstrate the theoretical importance of this approach in restoring the concept of bprogressQ to its proper place in evolutionary biology showing why, over the last 575 million years of evolutionary competition of finding and filling new niches, there has always been (and likely always will be) broom at the top.
Are fast explorers slow reactors? Linking personality type and anti-predator behaviour
Are fast explorers slow reactors? Linking personality type and anti-predator behaviour
Katherine A. Jones and
Jean-Guy J. Godin; 2010
http://rspb.royalsocietypublishing.org/content/277/1681/625.full
Abstract
Response delays to predator attack may be adaptive, suggesting that latency to respond does not always reflect predator detection time, but can be a decision based on starvation–predation risk trade-offs. In birds, some anti-predator behaviours have been shown to be correlated with personality traits such as activity level and exploration. Here, we tested for a correlation between exploration behaviour and response latency time to a simulated fish predator attack in a fish species, juvenile convict cichlids (Amatitlania nigrofasciata). Individual focal fish were subjected to a standardized attack by a robotic fish predator while foraging, and separately given two repeated trials of exploration of a novel environment. We found a strong positive correlation between exploration and time taken to respond to the predator model. Fish that were fast to explore the novel environment were slower to respond to the predator. Our study therefore provides some of the first experimental evidence for a link between exploration behaviour and predator-escape behaviour. We suggest that different behavioural types may differ in how they partition their attention between foraging and anti-predator vigilance.
http://rspb.royalsocietypublishing.org/content/277/1681/625.full
Abstract
Response delays to predator attack may be adaptive, suggesting that latency to respond does not always reflect predator detection time, but can be a decision based on starvation–predation risk trade-offs. In birds, some anti-predator behaviours have been shown to be correlated with personality traits such as activity level and exploration. Here, we tested for a correlation between exploration behaviour and response latency time to a simulated fish predator attack in a fish species, juvenile convict cichlids (Amatitlania nigrofasciata). Individual focal fish were subjected to a standardized attack by a robotic fish predator while foraging, and separately given two repeated trials of exploration of a novel environment. We found a strong positive correlation between exploration and time taken to respond to the predator model. Fish that were fast to explore the novel environment were slower to respond to the predator. Our study therefore provides some of the first experimental evidence for a link between exploration behaviour and predator-escape behaviour. We suggest that different behavioural types may differ in how they partition their attention between foraging and anti-predator vigilance.
Genetic Contributions to Antisocial Personality and Behavior: A Meta-Analytic Review From an Evolutionary Perspective
Genetic Contributions to Antisocial Personality and Behavior: A Meta-Analytic Review From an Evolutionary Perspective
Christopher J Ferguson; 2010
http://www.tamiu.edu/~cferguson/evmeta.pdf
Abstract
Evidence from behavioral genetics supports the conclusion that a significant amount of the variance in antisocial personality and behavior (APB) is due to genetic contributions. Many scientific fields such as psychology, medicine, and criminal justice struggle to incorporate this information with preexisting paradigms that focused exclusively on external or learned etiology of antisocial behavior. The current paper presents a meta-analytic review of behavioral genetic etiological studies of APB. Results indicated that 56% of the variance in APB can be explained through genetic influences, with 11% due to shared non-genetic influences, and 31% due to unique non-genetic influences. This data is discussed in relation to evolutionary psychological theory.
Christopher J Ferguson; 2010
http://www.tamiu.edu/~cferguson/evmeta.pdf
Abstract
Evidence from behavioral genetics supports the conclusion that a significant amount of the variance in antisocial personality and behavior (APB) is due to genetic contributions. Many scientific fields such as psychology, medicine, and criminal justice struggle to incorporate this information with preexisting paradigms that focused exclusively on external or learned etiology of antisocial behavior. The current paper presents a meta-analytic review of behavioral genetic etiological studies of APB. Results indicated that 56% of the variance in APB can be explained through genetic influences, with 11% due to shared non-genetic influences, and 31% due to unique non-genetic influences. This data is discussed in relation to evolutionary psychological theory.
Longitudinal Associations of Cognitive Ability, Personality Traits and School Grades with Antisocial Behaviour
Longitudinal Associations of Cognitive Ability, Personality Traits and School Grades with Antisocial Behaviour
Rene Mottus et al., 2011
http://psych.ut.ee/~jyri/en/M%F5ttus-Guljajev_EJP2012.pdf
Abstract
This study investigated the role of adolescents’ cognitive ability, personality traits and school success in predicting later criminal behaviour. Cognitive ability, the five-factor model personality traits and the school grades of a large sample of Estonian schoolboys (N ¼ 1919) were measured between 2001 and 2005. In 2009, judicial databases were searched to identify participants who had been convicted of misdemeanours or criminal offences. Consistent with previous findings, having a judicial record was associated with lower cognitive ability, grade point average, agreeableness, and conscientiousness and higher neuroticism. In multivariate path models, however, the contributions of cognitive ability and conscientiousness were accounted for by school grades and the effect of neuroticism was also accounted for by other variables, leaving grade point average and agreeableness the only independent predictors of judicial record status.
Rene Mottus et al., 2011
http://psych.ut.ee/~jyri/en/M%F5ttus-Guljajev_EJP2012.pdf
Abstract
This study investigated the role of adolescents’ cognitive ability, personality traits and school success in predicting later criminal behaviour. Cognitive ability, the five-factor model personality traits and the school grades of a large sample of Estonian schoolboys (N ¼ 1919) were measured between 2001 and 2005. In 2009, judicial databases were searched to identify participants who had been convicted of misdemeanours or criminal offences. Consistent with previous findings, having a judicial record was associated with lower cognitive ability, grade point average, agreeableness, and conscientiousness and higher neuroticism. In multivariate path models, however, the contributions of cognitive ability and conscientiousness were accounted for by school grades and the effect of neuroticism was also accounted for by other variables, leaving grade point average and agreeableness the only independent predictors of judicial record status.
Freitag, 22. März 2013
Disgust as an adaptive system for disease avoidance behaviour
Disgust as an adaptive system for disease avoidance behaviour
Valerie Curtis et al.; 2011
Abstract
Disgust is an evolved psychological system for protecting organisms from infection through disease avoidant behaviour. This ‘behavioural immune system’, present in a diverse array of species, exhibits universal features that orchestrate hygienic behaviour in response to cues of risk of contact with pathogens. However, disgust is also a dynamic adaptive system. Individuals show variation in pathogen avoidance associated with psychological traits like having a neurotic personality, as well as a consequence of being in certain physiological states such as pregnancy or infancy. Three specialized learning mechanisms modify the disgust response: the Garcia effect, evaluative conditioning and the law of contagion. Hygiene behaviour is influenced at the group level through social learning heuristics such as ‘copy the frequent’. Finally, group hygiene is extended symbolically to cultural rules about purity and pollution, which create social separations and are enforced as manners. Cooperative hygiene endeavours such as sanitation also reduce pathogen prevalence. Our model allows us to integrate perspectives from psychology, ecology and cultural evolution with those of epidemiology and anthropology. Understanding the nature of disease avoidance psychology at all levels of human organization can inform the design of programmes to improve public health.
Neurobehavioral Evidence for Changes in Dopamine System Activity During Adolescence
Neurobehavioral Evidence for Changes in Dopamine System Activity During Adolescence
Dustin Wahlstrom et al., 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2845533/
Abstract
Human adolescence has been characterized by increases in risk-taking, emotional lability, and deficient patterns of behavioral regulation. These behaviors have often been attributed to changes in brain structure that occur during this developmental period, notably alterations in gray and white matter that impact synaptic architecture in frontal, limbic, and striatal regions. In this review, we provide a rationale for considering that these behaviors may be due to changes in dopamine system activity, particularly overactivity, during adolescence relative to either childhood or adulthood. This rationale relies on animal data due to limitations in assessing neurochemical activity more directly in juveniles. Accordingly, we also present a strategy that incorporates molecular genetic techniques to infer the status of the underlying tone of the dopamine system across developmental groups. Implications for the understanding of adolescent behavioral development are discussed.
Dustin Wahlstrom et al., 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2845533/
Abstract
Human adolescence has been characterized by increases in risk-taking, emotional lability, and deficient patterns of behavioral regulation. These behaviors have often been attributed to changes in brain structure that occur during this developmental period, notably alterations in gray and white matter that impact synaptic architecture in frontal, limbic, and striatal regions. In this review, we provide a rationale for considering that these behaviors may be due to changes in dopamine system activity, particularly overactivity, during adolescence relative to either childhood or adulthood. This rationale relies on animal data due to limitations in assessing neurochemical activity more directly in juveniles. Accordingly, we also present a strategy that incorporates molecular genetic techniques to infer the status of the underlying tone of the dopamine system across developmental groups. Implications for the understanding of adolescent behavioral development are discussed.
Shared brain activity for aesthetic and moral judgments: implications for the Beauty-is-Good stereotype
Shared brain activity for aesthetic and moral judgments: implications for the Beauty-is-Good stereotype
Takashi Tsukiura and Roberta Cabeza; 2010
http://intl-scan.oxfordjournals.org/content/6/1/138.full
Abstract
The Beauty-is-Good stereotype refers to the assumption that attractive people possess sociably desirable personalities and higher moral standards. The existence of this bias suggests that the neural mechanisms for judging facial attractiveness and moral goodness overlap. To investigate this idea, we scanned participants with functional magnetic resonance imaging while they made attractiveness judgments about faces and goodness judgments about hypothetical actions. Activity in the medial orbitofrontal cortex increased as a function of both attractiveness and goodness ratings, whereas activity in the insular cortex decreased with both attractiveness and goodness ratings. Within each of these regions, the activations elicited by attractiveness and goodness judgments were strongly correlated with each other, supporting the idea of similar contributions of each region to both judgments. Moreover, activations in orbitofrontal and insular cortices were negatively correlated with each other, suggesting an opposing relationship between these regions during attractiveness and goodness judgments. These findings have implications for understanding the neural mechanisms of the Beauty-is-Good stereotype.
Takashi Tsukiura and Roberta Cabeza; 2010
http://intl-scan.oxfordjournals.org/content/6/1/138.full
Abstract
The Beauty-is-Good stereotype refers to the assumption that attractive people possess sociably desirable personalities and higher moral standards. The existence of this bias suggests that the neural mechanisms for judging facial attractiveness and moral goodness overlap. To investigate this idea, we scanned participants with functional magnetic resonance imaging while they made attractiveness judgments about faces and goodness judgments about hypothetical actions. Activity in the medial orbitofrontal cortex increased as a function of both attractiveness and goodness ratings, whereas activity in the insular cortex decreased with both attractiveness and goodness ratings. Within each of these regions, the activations elicited by attractiveness and goodness judgments were strongly correlated with each other, supporting the idea of similar contributions of each region to both judgments. Moreover, activations in orbitofrontal and insular cortices were negatively correlated with each other, suggesting an opposing relationship between these regions during attractiveness and goodness judgments. These findings have implications for understanding the neural mechanisms of the Beauty-is-Good stereotype.
Social power and approach-related neural activity
Social power and approach-related neural activity
Maarten A S Boksem et al.; 2008
Abstract
It has been argued that power activates a general tendency to approach whereas powerlessness activates a tendency to inhibit. The assumption is that elevated power involves reward-rich environments, freedom and, as a consequence, triggers an approach-related motivational orientation and attention to rewards. In contrast, reduced power is associated with increased threat, punishment and social constraint and thereby activates inhibition-related motivation. Moreover, approach motivation has been found to be associated with increased relative left-sided frontal brain activity, while withdrawal motivation has been associated with increased right sided activations. We measured EEG activity while subjects engaged in a task priming either high or low social power. Results show that high social power is indeed associated with greater left-frontal brain activity compared to low social power, providing the first neural evidence for the theory that high power is associated with approach-related motivation. We propose a framework accounting for differences in both approach motivation and goal-directed behaviour associated with different levels of power.
Maarten A S Boksem et al.; 2008
Abstract
It has been argued that power activates a general tendency to approach whereas powerlessness activates a tendency to inhibit. The assumption is that elevated power involves reward-rich environments, freedom and, as a consequence, triggers an approach-related motivational orientation and attention to rewards. In contrast, reduced power is associated with increased threat, punishment and social constraint and thereby activates inhibition-related motivation. Moreover, approach motivation has been found to be associated with increased relative left-sided frontal brain activity, while withdrawal motivation has been associated with increased right sided activations. We measured EEG activity while subjects engaged in a task priming either high or low social power. Results show that high social power is indeed associated with greater left-frontal brain activity compared to low social power, providing the first neural evidence for the theory that high power is associated with approach-related motivation. We propose a framework accounting for differences in both approach motivation and goal-directed behaviour associated with different levels of power.
Donnerstag, 21. März 2013
Contribution of Physical Fitness, Cerebrovascular Reserve and Cognitive Stimulation to Cognitive Function in Post-Menopausal Women
Contribution
of Physical Fitness, Cerebrovascular Reserve and Cognitive
Stimulation to Cognitive Function in Post-Menopausal Women
Abstract
Studies of the effects of physical fitness on cognition suggest that exercise can improve cognitive abilities in healthy older adults, as well as delay the onset of age-related cognitive decline. The mechanisms for the positive benefit of exercise and how these effects interact with other variables known to influence cognitive function (e.g., involvement in cognitive activities) are less well understood. The current study examined the associations between the physical fitness, cerebrovascular blood flow regulation and involvement in cognitive activities with neuropsychological function in healthy post-menopausal women.
Methods:
Forty-two healthy women between the ages of 55 and 90 were recruited. Physical fitness (VO2max), cerebrovascular reserve (cerebral blood flow during rest and response to an increase in end-tidal (i.e., arterial) PCO2), and cognitive activity (self-reported number and hours of involvement in cognitive activities) were assessed. The association of these variables with neuropsychological performance was examined through linear regression.
Results:
Physical fitness, cerebrovascular reserve and total number of cognitive activities (but not total hours) were independent predictors of cognitive function, particularly measures of overall cognitive performance, attention and executive function. In addition, prediction of neuropsychological performance was better with multiple variables than each alone.
Conclusions:
Cognitive function in older adults is associated with multiple factors, including physical fitness, cerebrovascular health and cognitive stimulation. Interestingly, cognitive stimulation effects appear related more to the diversity of activities, rather than the duration of activity. Further examination of these relationships is ongoing in a prospective cohort study.
Gail
A Eskes et al., 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2967376/Abstract
Studies of the effects of physical fitness on cognition suggest that exercise can improve cognitive abilities in healthy older adults, as well as delay the onset of age-related cognitive decline. The mechanisms for the positive benefit of exercise and how these effects interact with other variables known to influence cognitive function (e.g., involvement in cognitive activities) are less well understood. The current study examined the associations between the physical fitness, cerebrovascular blood flow regulation and involvement in cognitive activities with neuropsychological function in healthy post-menopausal women.
Methods:
Forty-two healthy women between the ages of 55 and 90 were recruited. Physical fitness (VO2max), cerebrovascular reserve (cerebral blood flow during rest and response to an increase in end-tidal (i.e., arterial) PCO2), and cognitive activity (self-reported number and hours of involvement in cognitive activities) were assessed. The association of these variables with neuropsychological performance was examined through linear regression.
Results:
Physical fitness, cerebrovascular reserve and total number of cognitive activities (but not total hours) were independent predictors of cognitive function, particularly measures of overall cognitive performance, attention and executive function. In addition, prediction of neuropsychological performance was better with multiple variables than each alone.
Conclusions:
Cognitive function in older adults is associated with multiple factors, including physical fitness, cerebrovascular health and cognitive stimulation. Interestingly, cognitive stimulation effects appear related more to the diversity of activities, rather than the duration of activity. Further examination of these relationships is ongoing in a prospective cohort study.
The neural basis of semantic and episodic forms of self-knowledge: Insights from Functional Neuroimaging
The neural basis of semantic and episodic forms of self-knowledge: Insights from Functional Neuroimaging
Arnaud D'Argembeau and Eric Salmon; 2011
http://www.ncbi.nlm.nih.gov/books/NBK51092/
Abstract
Throughout evolution, hominids have developed greater capacity to think about themselves in abstract and symbolic ways. This process has reached its apex in humans with the construction of a concept of self as a distinct entity with a personal history. This chapter provides a review of recent functional neuroimaging studies that have investigated the neural correlates of such "higher-level" aspects of the human self, focusing in particular on processes that allow individuals to consciously represent and reflect on their own personal attributes (semantic forms of self-knowledge) and experiences (episodic forms of self-knowledge). These studies point to the medial prefrontal cortex (MPFC) as a key neural structure for processing various kinds of self-referential information. We speculate that the MPFC may mediate dynamic processes that appraise and code the self-relatedness or self-relevance of information. This brain region may thus play a key role in creating the mental model of the self that is displayed in our mind at a given moment.
Arnaud D'Argembeau and Eric Salmon; 2011
http://www.ncbi.nlm.nih.gov/books/NBK51092/
Abstract
Throughout evolution, hominids have developed greater capacity to think about themselves in abstract and symbolic ways. This process has reached its apex in humans with the construction of a concept of self as a distinct entity with a personal history. This chapter provides a review of recent functional neuroimaging studies that have investigated the neural correlates of such "higher-level" aspects of the human self, focusing in particular on processes that allow individuals to consciously represent and reflect on their own personal attributes (semantic forms of self-knowledge) and experiences (episodic forms of self-knowledge). These studies point to the medial prefrontal cortex (MPFC) as a key neural structure for processing various kinds of self-referential information. We speculate that the MPFC may mediate dynamic processes that appraise and code the self-relatedness or self-relevance of information. This brain region may thus play a key role in creating the mental model of the self that is displayed in our mind at a given moment.
Dienstag, 19. März 2013
Sex differences in impulsivity : a meta-analysis
Sex differences in impulsivity : a meta-analysis
Cross CP et al., 2011
http://research-repository.st-andrews.ac.uk/bitstream/10023/2161/1/Cross2011PsychBullSexDifferences_WithAppendix1.pdf
Abstract
Men are overrepresented in socially problematic behaviors, such as aggression and criminal behavior, which have been linked to impulsivity. Our review of impulsivity is organized around the tripartite theoretical distinction between reward hypersensitivity, punishment hyposensitivity, and inadequate effortful control. Drawing on evolution try, criminological, developmental, and personality theories, we predicted that sex differences would be most pronounced in risky activities with men demonstrating greater sensation seeking, greater reward sensitivity, and lower punishment sensitivity. We predicted a small female advantage in effortful control. We analyzed 741 effect sizes from 277 studies, including psychometric and behavioral measures. Women were consistently more punishment sensitive (d = -0.33), but men did not show greater reward sensitivity (d = 0.01). Men showed significantly higher sensation seeking on questionnaire mea lures (d = 0.41) and on a behavioral risk-taking task (d = 0.36). Questionnaire measures of deficits in effortful control showed a very modest effect size in the male direction (d = 0.08). Sex differences were not found on delay discounting or executive function tasks. The results indicate a stronger sex difference in motivational rather than effortful or executive forms of behavior control. Specifically, they support evolutionary and biological theories of risk taking predicated on sex differences in punishment sensitivity. A clearer understanding of sex differences in impulsivity depends upon recognizing important distinctions between sensation seeking and impulsivity, between executive and effortful forms of control, and between impulsivity as a deficit and as a trait.
Cross CP et al., 2011
http://research-repository.st-andrews.ac.uk/bitstream/10023/2161/1/Cross2011PsychBullSexDifferences_WithAppendix1.pdf
Abstract
Men are overrepresented in socially problematic behaviors, such as aggression and criminal behavior, which have been linked to impulsivity. Our review of impulsivity is organized around the tripartite theoretical distinction between reward hypersensitivity, punishment hyposensitivity, and inadequate effortful control. Drawing on evolution try, criminological, developmental, and personality theories, we predicted that sex differences would be most pronounced in risky activities with men demonstrating greater sensation seeking, greater reward sensitivity, and lower punishment sensitivity. We predicted a small female advantage in effortful control. We analyzed 741 effect sizes from 277 studies, including psychometric and behavioral measures. Women were consistently more punishment sensitive (d = -0.33), but men did not show greater reward sensitivity (d = 0.01). Men showed significantly higher sensation seeking on questionnaire mea lures (d = 0.41) and on a behavioral risk-taking task (d = 0.36). Questionnaire measures of deficits in effortful control showed a very modest effect size in the male direction (d = 0.08). Sex differences were not found on delay discounting or executive function tasks. The results indicate a stronger sex difference in motivational rather than effortful or executive forms of behavior control. Specifically, they support evolutionary and biological theories of risk taking predicated on sex differences in punishment sensitivity. A clearer understanding of sex differences in impulsivity depends upon recognizing important distinctions between sensation seeking and impulsivity, between executive and effortful forms of control, and between impulsivity as a deficit and as a trait.
Sex Differences in Sensation Seeking / Impulsivity, Sensation Seeking & Reproductive Behaviour:
Impulsivity, sensation seeking and reproductive behaviour: A life history perspective
Lee T. Copping, Anne Campbell, Steven Muncer; 2013
Abstract
Impulsivity has often been invoked as a proximate driver of different life-history strategies. However, conceptualisations of “impulsivity” are inconsistent and ambiguities exist regarding which facets of impulsivity are actually involved in the canalisation of reproductive strategies. Two variables commonly used to represent impulsivity were examined in relation to reproductive behaviour. Results demonstrated that sensation seeking was significantly related to strategy-based behaviour, but impulsivity (defined as a failure to deliberate) was only weakly correlated. The effect of impulsivity disappeared when sensation seeking was controlled. Sex differences emerged for sensation seeking but not impulsivity. We conclude that “impulsivity” is not a unitary trait and that clearer distinctions should be made between facets of this construct.
[http://www.sciencedirect.com/science/article/pii/S0191886913000147]
Lee T. Copping, Anne Campbell, Steven Muncer; 2013
Abstract
Impulsivity has often been invoked as a proximate driver of different life-history strategies. However, conceptualisations of “impulsivity” are inconsistent and ambiguities exist regarding which facets of impulsivity are actually involved in the canalisation of reproductive strategies. Two variables commonly used to represent impulsivity were examined in relation to reproductive behaviour. Results demonstrated that sensation seeking was significantly related to strategy-based behaviour, but impulsivity (defined as a failure to deliberate) was only weakly correlated. The effect of impulsivity disappeared when sensation seeking was controlled. Sex differences emerged for sensation seeking but not impulsivity. We conclude that “impulsivity” is not a unitary trait and that clearer distinctions should be made between facets of this construct.
[http://www.sciencedirect.com/science/article/pii/S0191886913000147]
Sonntag, 17. März 2013
Are high-quality mates always attractive?
Are high-quality mates always attractive?
Katharina Riebel et al., 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2918774/
Abstract
Sexual selection theory posits that females should choose mates in a way that maximizes their reproductive success. But what exactly is the optimal choice? Most empirical research is based on the assumption that females seek a male of the highest possible quality (in terms of the genes or resources he can provide), and hence show directional preferences for indicators of male quality. This implies that attractiveness and quality should be highly correlated. However, females frequently differ in what they find attractive. New theoretical and empirical insights provide mounting evidence that a female’s own quality biases her judgement of male attractiveness, such that male quality and attractiveness do not always coincide. A recent experiment in songbirds demonstrated for the first time that manipulation of female condition can lead to divergent female preferences, with low-quality females actively preferring low-quality males over high-quality males. This result is in line with theory on state-dependent mate choice and is reminiscent of assortative mating preferences in humans. Here we discuss the implications of this work for the study of mate preferences.
----------
"What explains these divergent preferences? Theoretical models of statedependent mate choice point out that individuals in poor condition should be less attracted to high-quality mates when they cannot defend them, risk being deserted by them or are unlikely to be accepted by them in the first place. If pursuing these mates is likely to waste time or energy, it may pay to avoid highquality mates altogether and target lowquality partners instead. Holveck & Riebel’s work provides the first empirical evidence for this prediction, showing that high-quality males are not the most attractive mates for all females. Together with studies on other species this adds to growing evidence that attractiveness judgments may be closely related to the chooser’s own state."
"Birds of a feather flock together."
Katharina Riebel et al., 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2918774/
Abstract
Sexual selection theory posits that females should choose mates in a way that maximizes their reproductive success. But what exactly is the optimal choice? Most empirical research is based on the assumption that females seek a male of the highest possible quality (in terms of the genes or resources he can provide), and hence show directional preferences for indicators of male quality. This implies that attractiveness and quality should be highly correlated. However, females frequently differ in what they find attractive. New theoretical and empirical insights provide mounting evidence that a female’s own quality biases her judgement of male attractiveness, such that male quality and attractiveness do not always coincide. A recent experiment in songbirds demonstrated for the first time that manipulation of female condition can lead to divergent female preferences, with low-quality females actively preferring low-quality males over high-quality males. This result is in line with theory on state-dependent mate choice and is reminiscent of assortative mating preferences in humans. Here we discuss the implications of this work for the study of mate preferences.
----------
"What explains these divergent preferences? Theoretical models of statedependent mate choice point out that individuals in poor condition should be less attracted to high-quality mates when they cannot defend them, risk being deserted by them or are unlikely to be accepted by them in the first place. If pursuing these mates is likely to waste time or energy, it may pay to avoid highquality mates altogether and target lowquality partners instead. Holveck & Riebel’s work provides the first empirical evidence for this prediction, showing that high-quality males are not the most attractive mates for all females. Together with studies on other species this adds to growing evidence that attractiveness judgments may be closely related to the chooser’s own state."
"Birds of a feather flock together."
The Evolutionary Origins of Friendship
The Evolutionary Origins of Friendship
Robert M. Seyfarth and Dorothy L. Cheney; 2012
http://www.psych.upenn.edu/~seyfarth/Publications/annurev-psych-%20Friendship.pdf
Abstract
Convergent evidence from many species reveals the evolutionary origins of human friendship. In horses, elephants, hyenas, dolphins, monkeys, and chimpanzees, some individuals form friendships that last for years. Bonds occur among females, among males, or between males and females. Genetic relatedness affects friendships. In species where males disperse, friendships are more likely among females. If females disperse, friendships are more likely among males. Not all friendships, however, depend on kinship; many are formed between unrelated individuals. Friendships often involve cooperative interactions that are separated in time. They depend, at least in part, on the memory and emotions associated with past interactions. Applying the term “friendship” to animals is not anthropomorphic: Many studies have shown that the animals themselves recognize others’ relationships. Friendships are adaptive. Male allies have superior competitive ability and improved reproductive success; females with the strongest, most enduring friendships experience less stress, higher infant survival, and live longer.
-----
Goal of the paper: "Our goal is to shed light on the evolution and adaptive value of human friendship."
Robert M. Seyfarth and Dorothy L. Cheney; 2012
http://www.psych.upenn.edu/~seyfarth/Publications/annurev-psych-%20Friendship.pdf
Abstract
Convergent evidence from many species reveals the evolutionary origins of human friendship. In horses, elephants, hyenas, dolphins, monkeys, and chimpanzees, some individuals form friendships that last for years. Bonds occur among females, among males, or between males and females. Genetic relatedness affects friendships. In species where males disperse, friendships are more likely among females. If females disperse, friendships are more likely among males. Not all friendships, however, depend on kinship; many are formed between unrelated individuals. Friendships often involve cooperative interactions that are separated in time. They depend, at least in part, on the memory and emotions associated with past interactions. Applying the term “friendship” to animals is not anthropomorphic: Many studies have shown that the animals themselves recognize others’ relationships. Friendships are adaptive. Male allies have superior competitive ability and improved reproductive success; females with the strongest, most enduring friendships experience less stress, higher infant survival, and live longer.
-----
Goal of the paper: "Our goal is to shed light on the evolution and adaptive value of human friendship."
Body mass index across midlife and cognitive change in late life
Body mass index across midlife and cognitive change in late life
Dahl AK et al., 2012
Abstract
----------------------------------------------
Background:
High midlife body mass index (BMI) has been linked to a greater risk of dementia in late life, but few have studied the effect of BMI across midlife on cognitive abilities and cognitive change in a dementia-free sample.
Methods:
We investigated the association between BMI, measured twice across midlife (mean age 40 and 61 years, respectively), and cognitive change in four domains across two decades in the Swedish Adoption/Twin Study of Aging.
Results:
Latent growth curve models fitted to data from 657 non-demented participants showed that persons who were overweight/obese in early midlife had significantly lower cognitive performance across domains in late life and significantly steeper decline in perceptual speed, adjusting for cardio-metabolic factors. Both underweight and overweight/obesity in late midlife were associated with lower cognitive abilities in late life. However, the association between underweight and low cognitive abilities did not remain significant when weight decline between early and late midlife was controlled for.
Conclusion:
There is a negative effect on cognitive abilities later in life related to being overweight/obese across midlife. Moreover, weight decline across midlife rather than low weight in late midlife per se was associated with low cognitive abilities. Weight patterns across midlife may be prodromal markers of late life cognitive health.
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Dahl AK et al., 2012
Abstract
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Background:
High midlife body mass index (BMI) has been linked to a greater risk of dementia in late life, but few have studied the effect of BMI across midlife on cognitive abilities and cognitive change in a dementia-free sample.
Methods:
We investigated the association between BMI, measured twice across midlife (mean age 40 and 61 years, respectively), and cognitive change in four domains across two decades in the Swedish Adoption/Twin Study of Aging.
Results:
Latent growth curve models fitted to data from 657 non-demented participants showed that persons who were overweight/obese in early midlife had significantly lower cognitive performance across domains in late life and significantly steeper decline in perceptual speed, adjusting for cardio-metabolic factors. Both underweight and overweight/obesity in late midlife were associated with lower cognitive abilities in late life. However, the association between underweight and low cognitive abilities did not remain significant when weight decline between early and late midlife was controlled for.
Conclusion:
There is a negative effect on cognitive abilities later in life related to being overweight/obese across midlife. Moreover, weight decline across midlife rather than low weight in late midlife per se was associated with low cognitive abilities. Weight patterns across midlife may be prodromal markers of late life cognitive health.
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Body Mass Index, Change in Body Mass Index, and Survival in Old and Very Old Persons
Body Mass Index, Change in Body Mass Index, and Survival in Old and Very Old Persons
Dahl AK et al., 2013
Abstract
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Abstract
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OBJECTIVES:
To examine how body mass index (BMI) and change in BMI are associated with mortality in old (70-79) and very old (≥80) individuals.
DESIGN:
Pooled data from three multidisciplinary prospective population-based studies: OCTO-twin, Gender, and NONA.
SETTING:
Sweden.
PARTICIPANTS:
Eight hundred eighty-two individuals aged 70 to 95.
MEASUREMENTS:
BMI was calculated from measured height and weight as kg/m2 . Information about survival status and time of death was obtained from the Swedish Civil Registration System.
RESULTS:
Mortality hazard was 20% lower for the overweight group than the normal-underweight group (relative risk (RR) = 0.80, P = .011), and the mortality hazard for the obese group did not differ significantly from that of the normal-underweight group (RR = 0.93, P = .603), independent of age, education, and multimorbidity. Furthermore, mortality hazard was 65% higher for the BMI loss group than for the BMI stable group (RR = 1.65, P < .001) and 53% higher for the BMI gain group than for the BMI stable group (RR = 1.53, P = .001). Age moderated the BMI change differences. That is, the higher mortality risks associated with BMI loss and gain were less severe in very old age.
CONCLUSION:
Old persons who were overweight had a lower mortality risk than old persons who were of normal weight, even after controlling for weight change and multimorbidity. Persons who increased or decreased in BMI had a greater mortality risk than those who had a stable BMI, particularly those aged 70 to 79. This study lends further support to the belief that the World Health Organization guidelines for BMI are overly restrictive in old age.
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Being Overweight in Midlife Is Associated With Lower Cognitive Ability and Steeper Cognitive Decline in Late Life
Being Overweight in Midlife Is Associated With Lower Cognitive Ability and Steeper Cognitive Decline in Late Life
Anna Dahl et al., 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2796876/
Abstract
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Anna Dahl et al., 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2796876/
Abstract
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Background
Although an increasing body of evidence links being overweight in midlife with an increased risk for dementia in late life, no studies have examined the association between being overweight in midlife and cognitive ability in late life. Our aim was to examine the association between being overweight in midlife as measured by body mass index (BMI) and cognitive ability assessed over time.
Methods
Participants in the Swedish Adoption/Twin Study Aging were derived from a population-based sample. The participants completed baseline surveys in 1963 or 1973 (mean age 41.6 years, range 25–63 years). The surveys included questions about height, weight, diseases, and lifestyle factors. Beginning in 1986, the same individuals were assessed on neuropsychological tests every 3 years (except in 1995) until 2002. During the study period, 781 individuals who were 50 years and older (60% women) had at least one complete neuropsychological assessment. A composite score of general cognitive ability was derived from the cognitive test battery for each measurement occasion.
Results
Latent growth curve models adjusted for twinness showed that persons with higher midlife BMI scores had significantly lower general cognitive ability and significantly steeper longitudinal decline than their thinner counterparts. The association did not change substantially when persons who developed dementia during the study period were excluded from the analysis.
Conclusions
Higher midlife BMI scores precede lower general cognitive ability and steeper cognitive decline in both men and women. The association does not seem to be mediated by an increased risk for dementia.
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Samstag, 16. März 2013
The Hungry Mind: Intellectual Curiosity Is the Third Pillar of Academic Performance
The Hungry Mind: Intellectual Curiosity Is the Third Pillar of Academic Performance
Sophie von Stumm et al., 2012
http://www.drtomascp.com/uploads/HungryMind_PPS_2011.pdf
Abstract
Over the past century, academic performance has become the gatekeeper to institutions of higher education, shaping career paths and individual life trajectories. Accordingly, much psychological research has focused on identifying predictors of academic performance, with intelligence and effort emerging as core determinants. In this article, we propose expanding on the traditional set of predictors by adding a third agency: intellectual curiosity. A series of path models based on a meta-analytically derived correlation matrix showed that (a) intelligence is the single most powerful predictor of academic performance; (b) the effects of intelligence on academic performance are not mediated by personality traits; (c) intelligence, Conscientiousness (as marker of effort), and Typical Intellectual Engagement (as marker of intellectual curiosity) are direct, correlated predictors of academic performance; and (d) the additive predictive effect of the personality traits of intellectual curiosity and effort rival that the influence of intelligence. Our results highlight that a “hungry mind” is a core determinant of individual differences in academic achievement.
[Gute akademische Leistung bedarf insbesondere dreierlei Zutaten: A. Fleiß und Anstrengungsbereitschaft, B. Intelligenz und C. Interesse/Wissensdurst; Intellectual Curiosity dürfte im Wesentlichen mit dem Openness-Aspekt "Intellect" gleichbedeutend sein. ]
[The Openness-factor has two quite different aspects. Only one of these aspects (Intellect) plays an important role in academic performance. The second aspect and AP seem to be negatively correlated (at least in this study).]
--------------------------------
see also: Publications of De Young
http://www.tc.umn.edu/~cdeyoung/Publications.htm
Sophie von Stumm et al., 2012
http://www.drtomascp.com/uploads/HungryMind_PPS_2011.pdf
Abstract
Over the past century, academic performance has become the gatekeeper to institutions of higher education, shaping career paths and individual life trajectories. Accordingly, much psychological research has focused on identifying predictors of academic performance, with intelligence and effort emerging as core determinants. In this article, we propose expanding on the traditional set of predictors by adding a third agency: intellectual curiosity. A series of path models based on a meta-analytically derived correlation matrix showed that (a) intelligence is the single most powerful predictor of academic performance; (b) the effects of intelligence on academic performance are not mediated by personality traits; (c) intelligence, Conscientiousness (as marker of effort), and Typical Intellectual Engagement (as marker of intellectual curiosity) are direct, correlated predictors of academic performance; and (d) the additive predictive effect of the personality traits of intellectual curiosity and effort rival that the influence of intelligence. Our results highlight that a “hungry mind” is a core determinant of individual differences in academic achievement.
[Gute akademische Leistung bedarf insbesondere dreierlei Zutaten: A. Fleiß und Anstrengungsbereitschaft, B. Intelligenz und C. Interesse/Wissensdurst; Intellectual Curiosity dürfte im Wesentlichen mit dem Openness-Aspekt "Intellect" gleichbedeutend sein. ]
[The Openness-factor has two quite different aspects. Only one of these aspects (Intellect) plays an important role in academic performance. The second aspect and AP seem to be negatively correlated (at least in this study).]
--------------------------------
see also: Publications of De Young
http://www.tc.umn.edu/~cdeyoung/Publications.htm
Freitag, 15. März 2013
The General Factor of Personality and its relation to Self-Esteem in 628,640 Internet respondents
The General Factor of Personality and its relation to Self-Esteem in 628,640
Internet respondents
Stephen Erdle et al., 2009
http://psychology.uwo.ca/faculty/rushtonpdfs/2010%20Erdle%20GFP%20in%20PAID.pdf
Abstract
The purpose of this study was to explore the relationship between the General Factor of Personality (GFP) and Self-Esteem. We found a GFP that explained 57% of the reliable variance in a model that went from the Big Five to the Big Two to the Big One in a secondary analysis of a sample of 628,640 participants, reported by Erdle, Gosling, and Potter (2009) using an interactive website on the Internet. The GFP in turn accounted for 67% of the variance in the measure of Self-Esteem. We discuss alternative possibilities to account for the relationship.
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"Indeed it could even be concluded that in this sample, the GFP is mostly Self-Esteem, since the two constructs share 67% of common variance."
Mental time travel and the shaping of the human mind
Mental time travel and the shaping of the human mind
Thomas Suddendorf et al., 2009
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2666704/
Abstract
Episodic memory, enabling conscious recollection of past episodes, can be distinguished from semantic memory, which stores enduring facts about the world. Episodic memory shares a core neural network with the simulation of future episodes, enabling mental time travel into both the past and the future. The notion that there might be something distinctly human about mental time travel has provoked ingenious attempts to demonstrate episodic memory or future simulation in non-human animals, but we argue that they have not yet established a capacity comparable to the human faculty. The evolution of the capacity to simulate possible future events, based on episodic memory, enhanced fitness by enabling action in preparation of different possible scenarios that increased present or future survival and reproduction chances. Human language may have evolved in the first instance for the sharing of past and planned future events, and, indeed, fictional ones, further enhancing fitness in social settings.
Thomas Suddendorf et al., 2009
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2666704/
Abstract
Episodic memory, enabling conscious recollection of past episodes, can be distinguished from semantic memory, which stores enduring facts about the world. Episodic memory shares a core neural network with the simulation of future episodes, enabling mental time travel into both the past and the future. The notion that there might be something distinctly human about mental time travel has provoked ingenious attempts to demonstrate episodic memory or future simulation in non-human animals, but we argue that they have not yet established a capacity comparable to the human faculty. The evolution of the capacity to simulate possible future events, based on episodic memory, enhanced fitness by enabling action in preparation of different possible scenarios that increased present or future survival and reproduction chances. Human language may have evolved in the first instance for the sharing of past and planned future events, and, indeed, fictional ones, further enhancing fitness in social settings.
Donnerstag, 14. März 2013
Relating introspective accuracy to individual differences in brain structure
Relating introspective accuracy to individual differences in brain structure
Stephen M Fleming et al., 2011
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3173849/
Abstract
Our ability to introspect about self-performance is core to human subjective experience, but the neuroanatomical basis of this ability is unknown. Such accurate introspection requires discriminating correct from incorrect decisions, a capacity that varies substantially across individuals. We dissociated variation in introspective ability from objective performance in a simple perceptual decision task, allowing us to determine whether this inter-individual variability was associated with a distinct neural substrate. We show that introspective ability is correlated with gray matter volume in anterior prefrontal cortex, a region which shows striking evolutionary development in humans. Moreover, inter-individual variability in introspective ability also correlated with white matter microstructure connected with this area of prefrontal cortex. Our findings point to a focal neuroanatomical substrate for introspective ability, a substrate distinct from that supporting primary perception.
Stephen M Fleming et al., 2011
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3173849/
Abstract
Our ability to introspect about self-performance is core to human subjective experience, but the neuroanatomical basis of this ability is unknown. Such accurate introspection requires discriminating correct from incorrect decisions, a capacity that varies substantially across individuals. We dissociated variation in introspective ability from objective performance in a simple perceptual decision task, allowing us to determine whether this inter-individual variability was associated with a distinct neural substrate. We show that introspective ability is correlated with gray matter volume in anterior prefrontal cortex, a region which shows striking evolutionary development in humans. Moreover, inter-individual variability in introspective ability also correlated with white matter microstructure connected with this area of prefrontal cortex. Our findings point to a focal neuroanatomical substrate for introspective ability, a substrate distinct from that supporting primary perception.
Gender Differences in Personality across the Ten Aspects of the Big Five
Gender Differences in Personality across the Ten Aspects of the Big Five
Weisberg Y J et al.; 2011
Abstract
This paper investigates gender differences in personality traits, both at the level of the Big Five and at the sublevel of two aspects within each Big Five domain. Replicating previous findings, women reported higher Big Five Extraversion, Agreeableness, and Neuroticism scores than men. However, more extensive gender differences were found at the level of the aspects, with significant gender differences appearing in both aspects of every Big Five trait. For Extraversion, Openness, and Conscientiousness, the gender differences were found to diverge at the aspect level, rendering them either small or undetectable at the Big Five level. These findings clarify the nature of gender differences in personality and highlight the utility of measuring personality at the aspect level.
Abstract
This paper investigates gender differences in personality traits, both at the level of the Big Five and at the sublevel of two aspects within each Big Five domain. Replicating previous findings, women reported higher Big Five Extraversion, Agreeableness, and Neuroticism scores than men. However, more extensive gender differences were found at the level of the aspects, with significant gender differences appearing in both aspects of every Big Five trait. For Extraversion, Openness, and Conscientiousness, the gender differences were found to diverge at the aspect level, rendering them either small or undetectable at the Big Five level. These findings clarify the nature of gender differences in personality and highlight the utility of measuring personality at the aspect level.
Mittwoch, 13. März 2013
Prefrontal and striatal dopaminergic genes predict individual differences in exploration and exploitation
Prefrontal and striatal dopaminergic genes predict individual differences in exploration and exploitation
Michael J Frank et al., 2009
http://diyhpl.us/~bryan/papers2/neuro/Prefrontal%20and%20striatal%20dopaminergic%20genes%20predict%20individual%20differences%20in%20exploration%20and%20exploitation.pdf
Abstract
The basal ganglia support learning to exploit decisions that have yielded positive outcomes in the past. In contrast, limited evidence implicates the prefrontal cortex in the process of making strategic exploratory decisions when the magnitude of potential outcomes is unknown. Here we examine neurogenetic contributions to individual differences in these distinct aspects of motivated human behavior, using a temporal decision-making task and computational analysis. We show that two genes controlling striatal dopamine function, DARPP-32 (also called PPP1R1B) and DRD2, are associated with exploitative learning to adjust response times incrementally as a function of positive and negative decision outcomes. In contrast, a gene primarily controlling prefrontal dopamine function (COMT) is associated with a particular type of ‘directed exploration’, in which exploratory decisions are made in proportion to Bayesian uncertainty about whether other choices might produce outcomes that are better than the status quo. Quantitative model fits reveal that genetic factors modulate independent parameters of a reinforcement learning system.
Dienstag, 12. März 2013
Association of adolescent obesity and lifetime nulliparity
Association of adolescent obesity and lifetime nulliparity – SWAN, the study of women's health across the nation
Alex J Polotzky et al., 2011
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2891509/
Abstract
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Objective
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[There seems to be a connection between high sugar diets and obesity. Maybe these diets also cause a lowered fertility in women.]
Abstract
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Objective
To evaluate whether adolescent obesity is associated with difficulties for becoming pregnant later in life.
Design
Cross-sectional analysis of baseline data from a longitudinal cohort
Setting
Multiethnic, community-based observational study of US women
Patient(s)
3154 midlife women
Main Outcome Measure(s)
Lifetime nulliparity and lifetime nulligravidity
Result(s)
527 women (16.7%) women had never delivered a baby. Participants were categorized by self-reported high school body mass index (BMI): underweight (< 18.5 kg/m2), normal (18.5 to 24.9 kg/m2), overweight (25-29.9 kg/m2), and obese (> 30 kg/m2). The prevalence of lifetime nulliparity increased progressively across the high school BMI categories: 12.7%, 16.7%, 19.2%, and 30.9%, respectively (p<0.001). Multivariable logistic regression analysis confirmed that women who were obese adolescents had significantly higher odds of remaining childless as compared to normal weight women (odds ratio [OR] 2.84, 95% confidence intervals [CI] 1.59 to 5.10) after adjusting for adult BMI, history of non-gestational amenorrhea, marital status, ethnicity, study site, and measures of socioeconomic status. Furthermore, adolescent obesity was associated with lifetime nulligravidity (OR 3.93, 95% CI 2.12 to 7.26).
Conclusion(s)
Adolescent obesity is associated with lifetime nulliparity and nulligravidity in midlife U.S. women.
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[There seems to be a connection between high sugar diets and obesity. Maybe these diets also cause a lowered fertility in women.]
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