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

Negative emotion-conditioned prepulse induces the attentional enhancement of prepulse inhibition in humans

Prepulse inhibition (PPI) is a reduction of the acoustic startle reflex (ASR) when the startling stimulus is preceded by a weaker and non-startling stimulus (i.e., prepulse). Previous studies have revealed that PPI can be top-down modulated by selective attention to the fear-conditioned prepulse in animals. However, few researchers have tested this assumption in humans. Thus, in this study, the negative emotional-conditioned prepulse (CS+) was used to explore whether it could improve participants' attention, and further improve the PPI. The results showed that the CS+ prepulse increased the PPI only in females, PPI produced by CS+ prepulse was larger in females than in males, and the perceptual spatial attention further improved the PPI in both females and males. The results suggested that the PPI was affected by emotional, perceptual spatial attention, and sex. These findings highlight an additional method to measure top-down attentional regulation of PPI in humans. Which may offer a useful route to enhance the diagnosis of affective disorders, such as anxiety, depression, and post-traumatic stress disorder.

Enduring impact of childhood adversity: Affective modulation of acoustic startle response during pregnancy and postpartum

BACKGROUND

Women with a history of adverse childhood experiences (ACEs) enter pregnancy and the postpartum with a physiologic system programmed by early life stress, potentially reflected in psychophysiologic reactivity.

METHODS

We enrolled pregnant, psychiatrically healthy women ≥18 years old. Using the ACE Questionnaire, women were categorized as high (≥2 ACEs; n = 77) or low ACE (<2 ACEs; n = 72). Participants completed an affective modulation of acoustic startle response (ASR) task during pregnancy and postpartum, in which ASR magnitude was measured while participants viewed pleasant, unpleasant, and neutral pictures. Two types of control trials were included (habituation trials presented at baseline and intertrial interval trials presented when no picture was present).

RESULTS

Among high ACE women, ASR was significantly higher postpartum compared with pregnancy in the unpleasant (p = 0.002, β = 0.46, 95% CI [0.18, 0.74], χ2 = 10.12, z = 3.18) and intertrial interval trials (p = 0.002, β = 0.44, 95% CI [0.16, 0.73], χ2 = 9.25, z = 3.04), accounting for multiple comparisons using a Bonferroni correction at p < 0.005. Among low ACE women, ASR was similar in pregnancy and postpartum.

CONCLUSIONS

Physiological reactivity increased in high ACE women from pregnancy to postpartum, but no change was observed in low ACE women.

Psychiatric Symptoms Across the Menstrual Cycle in Adult Women: A Comprehensive Review

LEARNING OBJECTIVE

After participating in this activity, learners should be better able to:• Discuss and outline the general and overlapping effects of the menstrual cycle on women's mental health.

ABSTRACT

A growing body of research demonstrates menstrual cycle-dependent fluctuations in psychiatric symptoms; these fluctuations can therefore be considered as prevalent phenomena. Possible mechanisms underlying these fluctuations posit behavioral, psychological, and neuroendocrine influences. Recent reviews document cyclic exacerbation of symptoms and explore these mechanisms in the context of specific and often single disorders. The question remains, however, as to whether there are general and overlapping effects of the menstrual cycle on women's mental health. To address this gap, we synthesized the literature examining the exacerbation of a variety of psychiatric symptoms across the menstrual cycle in adult women. Results show that the premenstrual and menstrual phases are most consistently implicated in transdiagnostic symptom exacerbation. Specifically, strong evidence indicates increases in psychosis, mania, depression, suicide/suicide attempts, and alcohol use during these phases. Anxiety, stress, and binge eating appear to be elevated more generally throughout the luteal phase. The subjective effects of smoking and cocaine use are reduced during the luteal phase, but fewer data are available for other substances. Less consistent patterns are demonstrated for panic disorder, symptoms of posttraumatic stress disorder, and borderline personality disorder, and it is difficult to draw conclusions for symptoms of generalized anxiety disorder, social anxiety disorder, obsessive-compulsive disorder, and trichotillomania because of the limited data. Future research should focus on developing standardized approaches to identifying menstrual cycle phases and adapting pharmacological and behavioral interventions for managing fluctuations in psychiatric symptoms across the menstrual cycle.

What Pre-clinical Rat Models Can Tell Us About Anxiety Across the Menstrual Cycle in Healthy and Clinically Anxious Humans

PURPOSE OF REVIEW

Anxiety symptoms increase during the peri-menstrual phase of the menstrual cycle in people with anxiety disorders. Whether this reflects a heightened variant of normal menstrual-related changes in psychological states experienced by healthy (i.e. non-anxious) people is unknown. Moreover, menstrual-related change in anxiety symptoms is a poorly understood phenomenon, highlighting a need for pre-clinical models to aid mechanistic discovery. Here, we review recent evidence for menstrual effects on anxiety-like features in healthy humans as a counterpart to recent reviews that have focused on clinically anxious populations. We appraise the utility of rodent models to identify mechanisms of menstrual effects on anxiety and offer suggestions to harmonise methodological practices across species to advance knowledge in this field.

RECENT FINDINGS

Consistent with reports in clinical populations, some evidence indicates anxiety symptoms increase during the peri-menstrual period in healthy people, although null results have been reported, and these effects are heterogeneous across studies and individuals. Studies in rats show robust increases in anxiety during analogous phases of the oestrous cycle. Studies in female rats are useful to identify the evolutionarily conserved biological mechanisms of menstrual-related changes in anxiety. Future experimental approaches in rats should model the heterogeneity observed in human studies to increase alignment across species and advance understanding of the individual factors that increase the propensity to experience menstrual-related changes in anxiety.

Both Val158Met Polymorphism of Catechol-O-Methyltransferase Gene and Menstrual Cycle Affect Prepulse Inhibition but Not Attentional Modulation of Prepulse Inhibition in Younger-Adult Females

Prepulse inhibition (PPI) can be modulated by both the Val158Met (rs4680) polymorphism of the Catechol-O-Methyltransferase (COMT) gene and the menstrual-cycle-related hormone fluctuations, each of which affects the subcortical/cortical dopamine metabolism. PPI can also be modulated by attention. The attentional modulation of PPI (AMPPI) is sensitive to psychoses. Whether the Val158Met polymorphism affects the AMPPI in female adults at different menstrual-cycle phases is unknown. This study examined whether AMPPI and/or PPI are affected by the Val158Met polymorphism in 177 younger-adult females whose menstrual cycles were mutually different across the menstruation, proliferative, or secretory phases. The AMPPI was evaluated by comparing PPI under the condition of the auditory precedence-effect-induced perceptual spatial separation between the prepulse stimulus and a masking noise (PPI_PSS) against that under the condition of the precedence-effect-induced perceptual spatial co-location (PPI_PSC). The results showed that both the menstrual cycle and the COMT Val158Met polymorphism affected both PPI_PSC and PPI_PSS, but not the AMPPI (difference between PPI_PSS and PPI_PSC). Moreover, throughout the menstrual cycle, both PPI_PSC and PPI_PSS decreased monotonously in Val/Val-carrier participants. However, the decreasing pattern was not overserved in either Met/Met-carrier or Met/Val-carrier participants. Thus, in healthy younger-adult females, PPI_PSC and PPI_PSS, but not the AMPPI, is vulnerable to changes of ovarian hormones, and the COMT Val158Met polymorphism also has a modulating effect on this menstrual-cycle-dependent PPI variation. In contrast, the AMPPI seems to be more steadily trait-based, less vulnerable to ovarian hormone fluctuations, and may be useful in assisting the diagnosis of schizophrenia in female adults.

Sex differences and personality in the modulation of the acoustic startle reflex

The modulation of the eyeblink component of the acoustic startle reflex (ASR) has been used to study human motivation, attention, and emotion towards affective stimuli of different valence. However, sex and individual differences in personality have been rather overlooked concerning the change in the ASR to brief affective sequences. In this study, we aimed to evaluate sex differences in the ASR, together with the influence of sensitivity to punishment (SP) and sensitivity to reward (SR) in the affective modulation of the ASR to pleasant and unpleasant pictures. We addressed this topic with a latent curve model (LCM) representing the change in the ASR of an extensive group of men (n = 166) and women (n = 109). There was a significant habituation of the ASR to the pleasant pictures, and a significant sensitization of the ASR to the unpleasant pictures. Both effects were higher and more variable for women than for men. There were in addition interactive and quadratic effects of SP and SR on the ASR to the pleasant and unpleasant pictures. Men and women with extreme scores in SP, and women with low scores in SR habituated faster to the pleasant stimuli. For men scoring low in SP, higher scores in SR related with an attenuated initial ASR to the unpleasant stimuli. Women with extreme scores in SP had a higher initial ASR to the unpleasant stimuli. There were remarkable asymmetries between men and women concerning personality effects on the change in the ASR to affective stimuli.

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

PURPOSE OF REVIEW

Neuroactive steroid hormones, such as estradiol and progesterone, likely play a role in the pathophysiology of female-specific psychiatric disorders such as premenstrual dysphoric disorder (PMDD) and postpartum depression and may contribute to the marked sex differences observed in the incidence and presentation of affective disorders. However, few tools are available to study the precise contributions of these neuroactive steroids (NSs). In this review, we propose that the acoustic startle response (ASR), an objective measure of an organism's response to an emotional context or stressor, is sensitive to NSs. As such, the ASR represents a unique translational tool that may help to elucidate the contribution of NSs to sex differences in psychiatric disorders.

RECENT FINDINGS

Findings suggest that anxiety-potentiated startle (APS) and prepulse inhibition of startle (PPI) are the most robust ASR paradigms for assessing contribution of NSs to affective disorders, while affective startle response modulation (ASRM) appears less diagnostic of sex or menstrual cycle (MC) effects. However, few studies have appropriately used ASR to test a priori hypotheses about sex or MC differences. We recommend that ASR studies account for sex as a biological variable (SABV) and hormonal status to further knowledge of NS contribution to affective disorders.

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

Most work has shown that post-learning stress enhances long-term memory; however, there have been recent inconsistencies in this literature. The purpose of the present study was to examine further the effects of post-learning stress on long-term memory and to explore any sex differences that may exist. Male and female participants learned a list of 42 words that varied in emotional valence and arousal level. Following encoding, participants completed a free recall assessment and then submerged their hand into a bath of ice cold (stress) or lukewarm (no stress) water for 3 min. The next day, participants were given free recall and recognition tests. Stressed participants recalled more words than non-stressed participants 24h after learning. Stress also enhanced female participants' recall of arousing words when they were in the follicular, but not luteal, phase. These findings replicate previous work examining post-learning stress effects on memory and implicate the involvement of sex-related hormones in such effects.

Association of CRP genetic variation and CRP level with elevated PTSD symptoms and physiological responses in a civilian population with high levels of trauma

OBJECTIVE

Increased systemic inflammation is associated with stress-related psychopathology. Specifically, levels of the proinflammatory marker C-reactive protein (CRP) are elevated in individuals with posttraumatic stress disorder (PTSD). Furthermore, single-nucleotide polymorphisms (SNPs) in the CRP gene are associated with CRP level, risk for cardiovascular disease, and obesity. The authors examined whether polymorphisms within the CRP gene and increased CRP levels are associated with PTSD symptoms and fear physiology in a civilian population with high levels of trauma.

METHOD

Cross-sectional data and DNA samples were collected from 2,698 individuals recruited from an inner-city public hospital that serves a primarily African American, low-socioeconomic-status population. A subgroup of 187 participants participated in further interviews, testing, and physiological measures; of these, 135 were assessed using the fear-potentiated startle paradigm to assess fear-related phenotypes of PTSD.

RESULTS

One SNP within the CRP gene, rs1130864, was significantly associated with increased PTSD symptoms (N=2,692), including "being overly alert" as the most significant individual symptom (N=2,698). Additionally, CRP genotype was associated with the odds of PTSD diagnosis (N=2,692). This SNP was also associated with increased CRP level (N=137), and high CRP levels (>3 mg/L) were positively associated with PTSD symptoms (N=187) and fear-potentiated startle to a safety signal (N=135).

CONCLUSIONS

Together, these data indicate that genetic variability in the CRP gene is associated with serum CRP level and PTSD symptom severity, including that of hyperarousal symptoms. Elevated CRP levels were also associated with exacerbated fear-related psychophysiology and PTSD symptom ratings and diagnosis. These findings suggest a potential mechanism by which an increased proinflammatory state may lead to heightened PTSD symptoms.