Acute influences of estrogen and testosterone on divergent thinking and convergent thinking in postmenopausal women

We have found previously [1] an enhanced capability of divergent creative thinking in spontaneously cycling women during the ovulatory phase, which was linked to an increased dimensional complexity of ongoing electroencephalographic (EEG) activity. We asked whether these changes could be mediated by feedback influences of estrogen and testosterone, the release of which is enhanced during the ovulatory phase. In two groups of healthy postmenopausal women (mean age 58 yr) with low endogenous levels of gonadal steroids, respectively, estrogen and testosterone were administered transdermally over 3 days, at doses inducing plasma hormone concentrations comparable with those observed in young women around ovulation. The study was conducted according to a placebo-controlled cross-over design. Capabilities of divergent thought and convergent analytical thought, performance on motor perseveration and verbal memory were examined. EEG activity was recorded while subjects performed on tasks of thinking and during mental relaxation. Estrogen impaired divergent thinking (p<0.01) and enhanced convergent thinking, motor perseveration, and memory for the initial wordlist (p<0.05, for all tests). In parallel, EEG dimensional complexity was reduced (p<0.05). Overall these changes indicate an estrogen induced shift from a ‘divergent’ towards a more ‘convergent’ mode of processing. Although overall less consistent, effects of testosterone were opposite to those of estrogen. It increased performance on some of the divergent thinking tasks (p<0.05), and tended to increase EEG dimensional complexity. The data suggest that testosterone rather than estrogen is a factor possibly contributing to the ovulatory enhancement in divergent thinking capabilities. References: [1] Krug et al. (1999). J Psychophysiol 13:163–172