title: Time of day effects on extroversion and salivation.
abstract: A circadian rhythm in the biological basis of extroversion-introversion (E-I) was hypothesized. Eighty subjects had their EPI E-I scores and lemon juice test (LJT) scores assessed at a.m. and at p.m. Results showed that : (a) there were high intra-test correlations for EPI E-I and LJT; (b) a significant correlation between EPI E-I and LJT was only found for a.m. and not for p.m.; and (c) there were large individual differences in LJT scores. It was concluded that a circadian rhythm of E-I could not be detected by these measures, and that applicability of the LJT to E-I depends upon the time of day of assessment and the measurement procedure employed.
mesh_terms: D000293:Adolescent; D000328:Adult; D001205:Ascorbic Acid; D002940:Circadian Rhythm; D002951:Citrates; D005120:Extraversion, Psychological; D005260:Female; D006801:Humans; D007439:Introversion, Psychological; D008297:Male; D010555:Personality Inventory; D012472:Salivation
chemical_list: D002951:Citrates; D001205:Ascorbic Acid