Greater sustained anxiety but not phasic fear in women compared to men.
Startle reflex studies in rodents indicate that female are more reactive than rats in experimental models of sustained anxiety but not in models of phasic fear (Toufexis, 2007). This study examined evidence for a similar effect in humans. Participants were exposed to three conditions, (1) predictable aversive shocks signaled by a cue, (2) unpredictable shocks, and (3) no shocks. Acoustic startle stimuli were delivered regularly across conditions. Phasic startle potential to the threat cue in the predictable condition was not affected by sex. In contrast, and consistent with basic research, the sustained increase in startle in the predictable and unpredictable conditions was greater in women compared to men. Animal studies suggest that such an effect may be mediated by the effects of sexual dimorphism in limbic structures, including the bed nucleus of the stria terminalis. However, psychosocial factors may also contribute to this effect.
Mood and Anxiety Disorder Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, MD, USA. christian.grillon@nih.gov
Christian
C
Grillon
D000328:Adult; D001007:Anxiety / Q000175:diagnosis* / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005239:Fear; D005260:Female; D006801:Humans; D008297:Male; D012737:Sex Factors