The spectrum of bipolar phenomena:

"Like the schizophrenia spectrum, the spectrum of bipolar phenomena ranges all the way from normal personality traits to severe psychotic symptoms. The broad dimension of personality underlying the risk of bipolar disorders is usually labeled hypomania. Hypomanic traits have two main facets: a facet of mood volatility (cyclothymia) that is strongly linked to neuroticism, and a facet of excitement and vitality (hyperthymia) that overlaps with extraversion and openness."

"Hypomanic traits are moderately correlated with schizotypy. Like positive schizotypy, hypomania is a robust predictor of artistic and verbal creativity, especially in combination with high intelligence. In addition to stimulating rich and unusual associations, hypomanic traits increase ideation fluency, allowing people to generate thoughts and ideas at a faster pace. Artists tend to be above average in hypomania, and creativity - both artistic and scientific - is elevated in the relatives of BD patients (Baas et al., 2016; Furnham et al., 2008, Jamison, 1993; Kyaga, 2015; Rawlings & Locarnini, 2008; Srivastava et al., 2010; Vellante et al., 2011). The evidence indicates that creativity is enhanced in hypomanic personalities and people with mild manic symptoms, but not in those experiencing full-blown manic episodes (Miklowitz & Johnson, 2013)."

Marco Del Giudice; Evolutionary Psychiatry