The impact of sex and menstrual cycle on the acoustic startle response

Association of CRP Genetic Variation and CRP Level With Elevated PTSD Symptoms and Physiological Responses in a Civilian Population With High Levels of Trauma

“…This effect of CRP on fear physiology was independent of PTSD symptoms, indicating that inflammation may increase vulnerability to a heightened fear response. The association between CRP level and FPS was stronger in women than men, supporting recent evidence for heightened FPS post-puberty in females compared to males (37) and the role of menstrual cycle phase in modulating FPS in females (38). This sex difference in the CRP/FPS relationship also corroborates previous findings of higher vulnerability to PTSD in females (39, 40) and data indicating sex differences in immune function that leave women more susceptible to increased inflammation (41, 42).…”

Post-learning stress enhances long-term memory and differentially influences memory in females depending on menstrual stage

“…reported that heightened progesterone, which typically peaks in the mid-late luteal phase, is positively correlated with memory recall of threatening images and may mediate cortisol response. Similarly, a study examining sex differences in acoustic startle response found that females in the late luteal phase exhibited enhanced startle response compared to both males and females in the follicular phase (Armbruster, Strobel, Kirschbaum, & Brocke, 2014). One hypothesis put forth to explain progesterone's enhancing effects for arousing material is that heightened progesterone levels increase sensitivity to sources associated with threat or danger (Conway et al, 2007;Derntl et al, 2008).…”

Startling Differences: Using the Acoustic Startle Response to Study Sex Differences and Neurosteroids in Affective Disorders

“…Clinically, this may be reflected in increased irritability or greater sensitivity to threat-related stimuli. Critical to this review, ASR provides a unique means for studying sex differences in pathophysiology, as particular ASR paradigms are sensitive to NSs [8,18,19,21,42,47,61,85,95,112]. Because ASR reflects differential activity of sexually divergent brain regions involved in the pathophysiology of affective disorders, ASR studies have important implications for identifying pathophysiological mechanisms and for developing more tailored treatments, particularly for disorders such as PMDD or perinatal depression.…”

“…Some studies failed to show differences in ASRM between women and men [15–17], or found sex differences only at certain points in the menstrual cycle. Women around ovulation and in the late luteal phase had larger ASR than men across affective conditions, but not in other phases of the menstrual cycle [18]. Ovulation and the late luteal phase are both characterized by fluctuations in estradiol, but without hormone measurements, the expected luteal phase increase in estradiol and progesterone cannot be confirmed.…”

“…A well-designed study to assess sex differences in ASRM in depression would include a priori hypotheses, a sufficient sample size to examine sex differences, and control for hormonal factors such as menstrual cycle or use of hormonal contraceptives in female participants. While ASR differences across cycle phase were apparent in healthy female controls [18], they were not apparent in women with MDD in the samples studied. On the other hand, preclinical studies suggest dysregulated ASR in females with a depressive phenotype.…”