Evidence from neuroimaging for the role of the menstrual cycle in the interplay of emotion and cognition

The effects of an acute Tai Chi on emotional memory and prefrontal cortex activation: a fNIRS study

Objective

Acute exercise has the potential to influence emotional memory and cortical hemodynamics, but the specific effects depend on the type of exercise. This study aimed to determine whether acute Tai Chi practice enhances emotional memory and prefrontal cortex activation compared to cycling and a control condition.

Methods

Using a within-subjects crossover design, 36 healthy university students completed three interventions: Tai Chi, cycling, and a resting control condition. Emotional memory performance was assessed before and after each intervention, and cortical hemodynamics were measured using functional near-infrared spectroscopy (fNIRS). The correlation between oxyhemoglobin (Oxy-Hb) concentration in the prefrontal cortex and emotional memory accuracy was analyzed.

Results

Compared to cycling and the control group, the Tai Chi intervention showed: (1) a significantly higher accuracy of positive emotional memory; (2) a greater increase in Oxy-Hb concentration in the left dorsolateral prefrontal cortex (L-DLPFC) during positive emotional memory tasks; (3) a stronger positive correlation between Oxy-Hb concentration in the L-DLPFC and emotional memory accuracy. In contrast, cycling improved positive emotional memory accuracy to a lesser extent, while the control group showed no significant changes.

Conclusion

Tai Chi, compared to cycling and rest, significantly enhanced positive emotional memory and L-DLPFC activation. These findings highlight the unique potential of Tai Chi to improve emotional memory through increased cortical activation, suggesting its effectiveness as a cognitive-emotional intervention.

The effects of psychostimulants in menstruating women with ADHD - A gender health gap in ADHD treatment?

INTRODUCTION

Attention-deficit/hyperactivity disorder is a chronic disorder that begins in childhood and often persists into adulthood. There are clinical observations of a cycle-dependent efficacy of psychostimulants in the treatment of ADHD. This relationship appears to be poorly researched.

METHODS

A narrative literature review is used to provide an overview of the current state of research and to draw implications for necessary future research.

RESULTS

Two studies examined the influence of psychostimulants on female sex hormones in women with ADHD. Another four studies suggested that ADHD symptoms worsen during the luteal phase of the menstrual cycle. Two studies provided a specific intervention tailored to the menstrual cycle.

DISCUSSION

Women with ADHD remain understudied and are likely to be mistreated. Investigation of the efficacy of psychostimulants in menstruating women with ADHD seems necessary and long overdue.

CONCLUSION

This highlights the gender health gap in our society and the need for further research to develop an understanding of behavioural and neuroscientific processes in order to adapt treatment strategies for women with ADHD.

Unveiling the Neurotransmitter Symphony: Dynamic Shifts in Neurotransmitter Levels during Menstruation

The menstrual cycle is an intricate biological process governed by hormonal changes that affect different facets of a woman's reproductive system. This review provides an overview of neurotransmitter alterations during different menstrual cycle phases and their effects on physiology and psychology. During the follicular phase, rising estrogen levels increase serotonin synthesis, enhancing mood, cognition, and pain tolerance. Estrogen may also influence dopamine levels, promoting motivation and reward sensitivity. GABA, involved in anxiety regulation, may be modulated by estrogen, inducing relaxation. Ovulation involves fluctuating dopamine and serotonin levels, potentially affecting motivation and positive mood. In the luteal phase, rising estrogen and progesterone may reduce serotonin availability, contributing to mood dysregulation, while enhanced GABAergic neurotransmission promotes sedation. Menstruation is characterized by declining estrogen and progesterone, potentially leading to mood disturbances, fluctuating GABAergic and dopaminergic neurotransmitter systems, relaxation, fatigue, motivation, and pleasure variations. Understanding neurotransmitter alterations during the menstrual cycle unveils the neurobiological mechanisms behind menstrual-related symptoms and disorders, facilitating targeted interventions. Pharmacological approaches targeting neurotransmitter systems, nutritional interventions, and lifestyle modifications show promise in managing menstrual symptoms. Future research should focus on further understanding neurotransmitter dynamics, personalized medicine, unexplored neurotransmitter roles, and integrating psychosocial factors. This knowledge will enhance well-being and quality of life for individuals experiencing menstrual-related challenges.

Interaction of sleep and emotion across the menstrual cycle

Menstruating individuals experience an increased risk for sleep and affective disorders, attributed in part to monthly oscillations in sex hormones. Emotional functioning and sleep continuity worsens during the perimenstrual phase of the menstrual cycle. This study examined the interactive effects of sleep, menstrual phase, and emotion in healthy women. Participants (N = 51, 43% Caucasian) aged 18-35 (m = 24 years) completed actigraphy and daily sleep/emotion diaries over two menstrual cycles (m days = 51.29). Diary and actigraphic total wake time at night (TWT) and daily ratings of positive and negative affect were compared across four phases of the menstrual cycle: perimenstrual, mid-follicular, periovulatory, and mid-luteal. Relationships between phase, sleep, and emotion were estimated using multistep hierarchical linear modelling. Mean menstrual cycle length was 28.61 ± 2.69 days. Perimenstrual phase positively predicted anger (p < 0.001) but no other emotions. Additionally, the perimenstrual phase predicted higher rates of TWT, such that diary TWT was 8-16 min longer during the perimenstrual (m = 67.54, SE = 3.37) compared to other phases (p < 0.001). Actigraphic TWT was also increased by 4-7 min (m = 61.54, SE = 3.37) in the perimenstrual phase (p < 0.001). Positive emotions were 0.05-0.10 points lower (p = 0.006-0.02) when TWT was greater in the perimenstrual phase. Greater rates of anger and sleep disruption were seen during the perimenstrual phase compared with other phases. When poor sleep occurred during the perimenstrual phase individuals reported reduced positive emotions. Reducing perimenstrual sleep disruptions may be an important intervention target for those at risk for affective disorders.

From movement to motivation: a proposed framework to understand the antidepressant effect of exercise

Depression is the leading cause of disability worldwide, exerting a profound negative impact on quality of life in those who experience it. Depression is associated with disruptions to several closely related neural and cognitive processes, including dopamine transmission, fronto-striatal brain activity and connectivity, reward processing and motivation. Physical activity, especially aerobic exercise, reduces depressive symptoms, but the mechanisms driving its antidepressant effects are poorly understood. Here we propose a novel hypothesis for understanding the antidepressant effects of exercise, centred on motivation, across different levels of explanation. There is robust evidence that aerobic exercise decreases systemic inflammation. Inflammation is known to reduce dopamine transmission, which in turn is strongly implicated in effort-based decision making for reward. Drawing on a broad range of research in humans and animals, we propose that by reducing inflammation and boosting dopamine transmission, with consequent effects on effort-based decision making for reward, exercise initially specifically improves 'interest-activity' symptoms of depression-namely anhedonia, fatigue and subjective cognitive impairment - by increasing propensity to exert effort. Extending this framework to the topic of cognitive control, we explain how cognitive impairment in depression may also be conceptualised through an effort-based decision-making framework, which may help to explain the impact of exercise on cognitive impairment. Understanding the mechanisms underlying the antidepressant effects of exercise could inform the development of novel intervention strategies, in particular personalised interventions and boost social prescribing.

A Female-Specific Treatment Group for ADHD-Description of the Programme and Qualitative Analysis of First Experiences

Background: The diagnostics and treatment of attention-deficit/hyperactivity disorder (ADHD) in women remain insufficient. Fluctuations of reproductive hormones during the premenstrual period, postpartum period, and (peri)menopause are neglected, even though they impact ADHD symptoms and associated mood disorders. Therefore, we created a female-specific treatment group for women with ADHD and premenstrual worsening of ADHD and/or mood symptoms. Methods: We describe the group programme and underlying rationale, offering a qualitative analysis of the participants' evaluation. Results: The seven bi-weekly sessions foreground the menstrual cycle and address several ADHD-specific topics in relation to this cyclical pattern. Concurrently, women track their menstrual cycle and (fluctuating) ADHD and mood symptoms with an adjusted premenstrual calendar. In total, 18 women (25-47 years) participated in three consecutive groups. We analysed the evaluation of the last group. Participants experienced the group as a safe and welcoming space. Recognition was valued by all. The topics discussed were deemed valuable, and the structure suited them well. Completing the premenstrual calendar augmented the awareness and recognition of individual cyclical symptoms. A lifespan approach increased self-understanding. Participants took their menstrual cycle more seriously, prioritising self-acceptance and self-care. Conclusions: Exploring a cyclical approach in a group setting seems to be a positive addition to treatment for female ADHD.

Female sex steroids and epilepsy: Part 1. A review of reciprocal changes in reproductive systems, cycles, and seizures

Seizures, antiseizure medications, and the reproductive systems are reciprocally entwined. In Section 2 of this review, we outline how seizures may affect the hypothalamic-pituitary-gonadal axis, thereby altering sex steroids, and changes in sex steroids across the menstrual cycle and changes in pharmacokinetics during pregnancy may alter seizure susceptibility. The literature indicates that females with epilepsy experience increased rates of menstrual disturbances and reproductive endocrine disorders. The latter include polycystic ovary syndrome, especially for females on valproate. Studies of fertility have yielded mixed results. We aim to summarize and attempt to detangle the existing knowledge on these reciprocal interactions. The menstrual cycle causes changes in seizure intensity and frequency for many females. When this occurs perimenstrually, during ovulation, or in association with an inadequate luteal phase, it is termed catamenial epilepsy. There is a clear biophysiological rationale for how the key female reproductive neurosteroids interact with the brain to alter the seizure threshold, and Section 3 outlines this important relationship. Critically, what remains unknown is the specific pathophysiology of catamenial epilepsy that describes why not all females are affected. There is a need for mechanism-focused investigations in humans to uncover the complexity of the relationship between reproductive hormones, menstrual cycles, and the brain.

Attention-deficit/hyperactivity disorder and the menstrual cycle: Theory and evidence

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that exhibits striking sex differences in symptoms, prevalence, and associated problems across development. Etiological factors and mechanisms underlying these sex differences remain one of the most understudied aspects of this disorder. The current paper seeks to provide a novel theoretical framework for understanding this phenomenon by reviewing evidence that females with ADHD may experience a "double whammy" of organizational and activational pubertal hormonal effects. We propose a novel theory of activational effects of cyclical circulating ovarian hormones on ADHD with increasing risk at times of rapid declines in estrogen. These declines may decrease executive function and trait control at two points of the cycle characterized by biphasic affective risk: (1) increases in approach/risk-taking behaviors at mid-cycle (periovulatory) and (2) increases in avoidance/negative affect perimenstrually. Low estrogen and control may then interact with increases in positive and negative affect, respectively, to increase hyperactivity-impulsivity symptoms post-ovulation and inattention symptoms perimenstrually. These interactions may be exacerbated by organizational pubertal effects on relatively overdeveloped limbic circuitry and adolescent-specific social pressures magnified in females with ADHD.

Binary metal oxide (NiO/SnO2) composite with electrochemical bifunction: Detection of neuro transmitting drug and catalysis for hydrogen evolution reaction

The synergetic effect between dual oxides in binary metal oxides (BMO) makes them promising electrode materials for the detection of toxic chemicals, and biological compounds. In addition, the interaction between the cations and anions of diverse metals in BMO tends to create more oxygen vacancies which are beneficial for energy storage devices. However, specifically targeted synthesis of BMO is still arduous. In this work, we prepared a nickel oxide/tin oxide composite (NiO/SnO2) through a simple solvothermal technique. The crystallinity, specific surface area, and morphology were fully characterized. The synthesized BMO is used as a bifunctional electrocatalyst for the electrochemical detection of dopamine (DPA) and for the hydrogen evolution reaction (HER). As expected, the active metals in the NiO/SnO2 composite afforded a higher redox current at a reduced redox potential with a nanomolar level detection limit (4 nm) and excellent selectivity. Moreover, a better recovery rate is achieved in the real-time detection of DPA in human urine and DPA injection solution. Compared to other metal oxides, NiO/SnO2 composite afforded lower overpotential (157 mV @10 mA cm-2), Tafel slope (155 mV dec-1), and long-term durability, with a minimum retention rate. These studies conclude that NiO/SnO2 composite can act as a suitable electrode modifier for electrochemical sensing and the HER.

Female-specific pharmacotherapy in ADHD: premenstrual adjustment of psychostimulant dosage

Objective

Attention-Deficit/Hyperactivity Disorder (ADHD) is a common neurodevelopmental condition which is underdiagnosed and undertreated in women. For decades, the ADHD field has called for more insight into female-specific therapy. Preliminary findings postulate that changes in sex hormones during the menstrual cycle may influence the effectiveness of psychostimulant medication. Yet, pharmacotherapeutic interventions tailored to women with ADHD remain scarce. Previously, our group showed an increase in mood symptoms in the premenstrual week in women with ADHD. Premenstrual worsening of depressive and ADHD symptoms represent a treatment challenge. In our adult ADHD clinic, we noted several women describing exacerbation of their ADHD and depressive symptoms in the premenstrual week and/or insufficient effect of their established dosage of psychostimulant. We responded to the need expressed by these women by increasing their stimulant dosage in the premenstrual week, while monitoring the response and side effects.

Methods

This community case study of nine consecutive women being treated for ADHD and co-occurring conditions (including depression and premenstrual dysphoric disorder), reports our local experience of increasing the individually prescribed psychostimulant dosage during the premenstrual period. We methodically monitored the effect of this increased dosage on ADHD symptoms, mood and somatic symptoms for the following 6-24 months.

Results

With premenstrual dose elevation, all nine women experienced improved ADHD and mood symptoms with minimal adverse events. Premenstrual inattention, irritability and energy levels improved, and now resembled the other non-premenstrual weeks more closely. All women decided to continue with the elevated premenstrual pharmacotherapy.

Discussion

Our preliminary results demonstrate potential benefits of increasing premenstrual psychostimulant dosage in women with ADHD, experiencing premenstrual worsening of ADHD and mood symptoms. The results concur with previous findings of diminished response to amphetamines in the late luteal phase. Increased dosage may help combat premenstrual worsening of cognitive and emotional symptoms in women with ADHD, with significant clinical implications. Better management of premenstrual ADHD and mood symptoms in vulnerable women can improve treatment outcome and meet an unmet need. However, implementation should be individually explored. Further investigation of luteal phase psychostimulant dose adjustment is required for safe, optimal and individualised treatment for women with ADHD.

Multivariate genetic analysis of personality and cognitive traits reveals abundant pleiotropy

Personality and cognitive function are heritable mental traits whose genetic foundations may be distributed across interconnected brain functions. Previous studies have typically treated these complex mental traits as distinct constructs. We applied the 'pleiotropy-informed' multivariate omnibus statistical test to genome-wide association studies of 35 measures of neuroticism and cognitive function from the UK Biobank (n = 336,993). We identified 431 significantly associated genetic loci with evidence of abundant shared genetic associations, across personality and cognitive function domains. Functional characterization implicated genes with significant tissue-specific expression in all tested brain tissues and brain-specific gene sets. We conditioned independent genome-wide association studies of the Big 5 personality traits and cognitive function on our multivariate findings, boosting genetic discovery in other personality traits and improving polygenic prediction. These findings advance our understanding of the polygenic architecture of these complex mental traits, indicating a prominence of pleiotropic genetic effects across higher order domains of mental function such as personality and cognitive function.

Effect of Menstrual Distress on Interpersonal Relationships, School Absenteeism, Work Productivity, and Academic Performance

Women's health has always been one of the major research areas to identify health patterns to understand the challenges women face and to provide essential support. As time changes, various new challenges and issues emerge around menstrual distress. More research is still needed to identify efficient physiological and psychological support strategies. The current chapter provides a detailed insight into how menstrual pain affects a woman and girl's interpersonal relationships, school presence, peer relations, productivity at the workplace, and academic performance. Further, the chapter captures various literature evidence on the effect of cultural and religious factors affecting menstruation. The chapter also emphasizes providing strategies and mapping down existing policies that are in action to address the challenges women face due to menstrual distress.

Brain-derived neurotrophic factor (BDNF) in perinatal depression: Side show or pivotal factor?

Perinatal depression is the most common psychiatric complication of pregnancy, with its detrimental effects on maternal and infant health widely underrated. There is a pressing need for specific molecular biomarkers, with pregnancy-related decline in brain-derived neurotrophic factor (BDNF) in the blood and downregulation of TrkB receptor in the brain reported in clinical and preclinical studies. In this review, we explore the emerging role of BDNF in reproductive biology and discuss evidence suggesting its deficiency as a risk factor for perinatal depression. With the increasing evidence for restoration of serum BDNF levels by antidepressant therapy, the strengthening association of perinatal depression with deficiency of BDNF supports its potential as a surrogate endpoint for preclinical and clinical studies.

A Mid-Cycle Rise in Positive and Drop in Negative Moods among Healthy Young Women: A Pilot Study

Clinically oriented studies of mood as a function of the menstrual cycle mainly address the negative moods in the premenstrual phase of the cycle. However, a periovulatory increase in positive emotions and motivations related to reproduction has also been noted. Thus, it has been suggested that the drop in mood during the luteal phase of the menstrual cycle might be a byproduct of elevated positive moods occurring mid-cycle. The aim of this prospective study was to compare both the positive and negative dimensions of mood across the menstrual cycle. A group of 60 healthy, normally cycling women assessed their mood throughout three phases of their menstrual cycles: the early follicular (low estradiol and progesterone), the late follicular (fertile phase; high estradiol, low progesterone) and the mid-luteal phase (high levels of both estradiol and progesterone). Repeated MANOVA evaluations showed a significant increase in positive (friendly, cheerful, focused, active) and a significant decrease in negative (anxious, depressed, fatigued, hostile) dimensions of mood mid-cycle, i.e., during the late follicular phase (η2 = 0.072−0.174, p < 0.05). Contrary to the widespread belief that negative moods are characteristic of the luteal phase (preceding the onset of the next cycle), the post hoc Bonferroni tests showed that none of the mood dimensions differed between the mid-luteal and early follicular phases of the cycle. The results held when controlling for relationship status and order of testing. This pattern of fluctuations is in accordance with the ovulatory-shift hypothesis, i.e., the notion that the emotions of attraction rise during a short window during which the conception is likely.

Thalamic regulation of frontal interactions in human cognitive flexibility

Interactions across frontal cortex are critical for cognition. Animal studies suggest a role for mediodorsal thalamus (MD) in these interactions, but the computations performed and direct relevance to human decision making are unclear. Here, inspired by animal work, we extended a neural model of an executive frontal-MD network and trained it on a human decision-making task for which neuroimaging data were collected. Using a biologically-plausible learning rule, we found that the model MD thalamus compressed its cortical inputs (dorsolateral prefrontal cortex, dlPFC) underlying stimulus-response representations. Through direct feedback to dlPFC, this thalamic operation efficiently partitioned cortical activity patterns and enhanced task switching across different contingencies. To account for interactions with other frontal regions, we expanded the model to compute higher-order strategy signals outside dlPFC, and found that the MD offered a more efficient route for such signals to switch dlPFC activity patterns. Human fMRI data provided evidence that the MD engaged in feedback to dlPFC, and had a role in routing orbitofrontal cortex inputs when subjects switched behavioral strategy. Collectively, our findings contribute to the emerging evidence for thalamic regulation of frontal interactions in the human brain.

Ovarian steroid hormones: A long overlooked but critical contributor to brain aging and Alzheimer's disease

Ovarian hormones, particularly 17β-estradiol, are involved in numerous neurophysiological and neurochemical processes, including those subserving cognitive function. Estradiol plays a key role in the neurobiology of aging, in part due to extensive interconnectivity of the neural and endocrine system. This aspect of aging is fundamental for women's brains as all women experience a drop in circulating estradiol levels in midlife, after menopause. Given the importance of estradiol for brain function, it is not surprising that up to 80% of peri-menopausal and post-menopausal women report neurological symptoms including changes in thermoregulation (vasomotor symptoms), mood, sleep, and cognitive performance. Preclinical evidence for neuroprotective effects of 17β-estradiol also indicate associations between menopause, cognitive aging, and Alzheimer's disease (AD), the most common cause of dementia affecting nearly twice more women than men. Brain imaging studies demonstrated that middle-aged women exhibit increased indicators of AD endophenotype as compared to men of the same age, with onset in perimenopause. Herein, we take a translational approach to illustrate the contribution of ovarian hormones in maintaining cognition in women, with evidence implicating menopause-related declines in 17β-estradiol in cognitive aging and AD risk. We will review research focused on the role of endogenous and exogenous estrogen exposure as a key underlying mechanism to neuropathological aging in women, with a focus on whether brain structure, function and neurochemistry respond to hormone treatment. While still in development, this research area offers a new sex-based perspective on brain aging and risk of AD, while also highlighting an urgent need for better integration between neurology, psychiatry, and women's health practices.

Neurobiological Alterations in Females With PTSD: A Systematic Review

Most females experience at least one traumatic event in their lives, but not all develop PTSD. Despite considerable research, our understanding of the key factors that constitute risk for PTSD among females is limited. Previous research has largely focused on sex differences, neglecting within group comparisons, thereby obviating differences between females who do and do not develop PTSD following exposure to trauma. In this systematic review, we conducted a search for the extent of existing research utilizing magnetic resonance imaging (MRI) to examine neurobiological differences among females of all ages, with and without PTSD. Only studies of females who met full diagnostic criteria for PTSD were included. Fifty-six studies were selected and reviewed. We synthesized here findings from structural MRI (sMRI), functional MRI (fMRI), diffusion tensor imaging (DTI), and resting state functional connectivity (rs-FC MRI) studies, comparing females with and without PTSD. A range of biopsychosocial constructs that may leave females vulnerable to PTSD were discussed. First, the ways timing and type of exposure to trauma may impact PTSD risk were discussed. Second, the key role that cognitive and behavioral mechanisms may play in PTSD was described, including rumination, and deficient fear extinction. Third, the role of specific symptom patterns and common comorbidities in female-specific PTSD was described, as well as sex-specific implications on treatment and parenting outcomes. We concluded by identifying areas for future research, to address the need to better understand developmental aspects of brain alterations, the differential impact of trauma types and timing, the putative role of neuroendocrine system in neurobiology of PTSD among females, and the impact of social and cultural factors on neurobiology in females with PTSD.

The regional effect of serum hormone levels on cerebral blood flow in healthy nonpregnant women

Sex hormones estrogen (EST) and progesterone (PROG) have received increased attention for their important physiological action outside of reproduction. While studies have shown that EST and PROG have significant impacts on brain function, their impact on the cerebrovascular system in humans remains largely unknown. To address this, we used a multi-modal magnetic resonance imaging (MRI) approach to investigate the link between serum hormones in the follicular phase and luteal phase of the menstrual cycle (MC) with measures of cerebrovascular function (cerebral blood flow [CBF]) and structure (intracranial artery diameter). Fourteen naturally cycling women were recruited and assessed at two-time points of their MC. CBF was derived from pseudo-continuous arterial spin labeling while diameters of the internal carotid and basilar artery was assessed using time of flight magnetic resonance angiography, blood samples were performed after the MRI. Results show that PROG and EST had opposing and spatially distinct effects on CBF: PROG correlated negatively with CBF in anterior brain regions (r = -.86, p < .01), while EST correlations were positive, yet weak and most prominent in posterior areas (r = .78, p < .01). No significant correlations between either hormone or intracranial artery diameter were observed. These results show that EST and PROG have opposing and regionally distinct effects on CBF and that this relationship is likely not due to interactions with large intracranial arteries. Considering that CBF in healthy women appears tightly linked to their current hormonal state, future studies should consider assessing MC-related hormone fluctuations in the design of functional MRI studies in this population.

The Menstrual Cycle Alters Resting-State Cortical Activity: A Magnetoencephalography Study

Resting-state neural oscillations are used as biomarkers for functional diseases such as dementia, epilepsy, and stroke. However, accurate interpretation of clinical outcomes requires the identification and minimisation of potential confounding factors. While several studies have indicated that the menstrual cycle also alters brain activity, most of these studies were based on visual inspection rather than objective quantitative measures. In the present study, we aimed to clarify the effect of the menstrual cycle on spontaneous neural oscillations based on quantitative magnetoencephalography (MEG) parameters. Resting-state MEG activity was recorded from 25 healthy women with normal menstrual cycles. For each woman, resting-state brain activity was acquired twice using MEG: once during their menstrual period (MP) and once outside of this period (OP). Our results indicated that the median frequency and peak alpha frequency of the power spectrum were low, whereas Shannon spectral entropy was high, during the MP. Theta intensity within the right temporal cortex and right limbic system was significantly lower during the MP than during the OP. High gamma intensity in the left parietal cortex was also significantly lower during the MP than during the OP. Similar differences were also observed in the parietal and occipital regions between the proliferative (the late part of the follicular phase) and secretory phases (luteal phase). Our findings suggest that the menstrual cycle should be considered to ensure accurate interpretation of functional neuroimaging in clinical practice.

Sex hormones and human brain function

Sex hormones have organizational and activational effects on the human brain and can interact with the neurotransmitter systems. These biologic mechanisms may have a far-reaching impact, with both behavioral consequences and structural as well as functional brain modulation. The impact of cycling hormone levels throughout the menstrual cycle on cognitive and emotion processing has especially received some attention recently. Therefore, the aim of this chapter is to give an overview of findings regarding the effects of estradiol and progesterone, but also testosterone, on functional brain domains comprising cognition, emotion, and reward processing.

Genome-Wide Association Study of Brain Alzheimer's Disease-Related Metabolic Decline as Measured by [18F] FDG-PET Imaging

BACKGROUND

Hypometabolism detected by fluorodeoxyglucose F18 positron emission tomography ([18F] FDG PET) is an early neuropathologic changes in Alzheimer's disease (AD) and provides important pathologic staging information.

OBJECTIVE

This study aimed to discover genetic interactions that regulate longitudinal glucose metabolic decline in AD-related brain regions.

METHODS

A total of 586 non-Hispanic white individuals from the Alzheimer's Disease Neuroimaging Initiative (ADNI) 1/GO/2 cohorts that met all quality control criteria were included in this study. Genome-wide association study of glucose metabolic decline in regions of interest (ROIs) was performed with linear regression under the additive genetic model.

RESULTS

We identified two novel variants that had a strong association with longitudinal metabolic decline in different ROI. Rs4819351-A in gene 1-acylglycerol-3-phosphate O-acyltransferase 3 (AGPAT3) demonstrated reduced metabolic decline in right temporal gyrus (p = 3.97×10-8, β= -0.016), while rs13387360-T in gene LOC101928196 demonstrated reduced metabolic decline in left angular gyrus (p = 1.69×10-8, β= -0.027).

CONCLUSION

Our results suggest two genome-wide significant SNPs (rs4819351, rs13387360) in AGPAT3 and LOC101928196 as protective loci that modulate glucose metabolic decline. These two genes should be further investigated as potential therapeutic target for neurodegeneration diseases.

Emotional Instability Relates to Ventral Striatum Activity During Reward Anticipation in Females

Both non-emotional symptoms, such as inattention, and symptoms of emotional instability (EI) are partially co-varying and normally distributed in the general population. Attention Deficit Hyperactivity Disorder (ADHD), which is associated with both inattention and emotional instability, has been related to lower reward anticipation activation in the ventral striatum. However, it is not known whether non-emotional dysregulation, such as inattention, or EI—or both—are associated with this effect. We hypothesized that altered reward processing relates specifically to EI. To test this, 29 healthy participants were recruited to this functional MRI study (n = 15 females). Reward processing was studied using a modified version of the Monetary Incentive Delay (MID) task. Brown Attention-Deficit Disorder Scales questionnaire was used to assess EI and inattention symptoms on a trait level. We observed less ventral striatal activation during reward anticipation related to the EI trait in females, also when controlling for the inattention trait, but not in the whole sample or males only. Our study suggests the existence of sex differences in the relationship between reward processing and EI/inattention traits.

Modulations of Insular Projections by Prior Belief Mediate the Precision of Prediction Error during Tactile Learning

Awareness for surprising sensory events is shaped by prior belief inferred from past experience. Here, we combined hierarchical Bayesian modeling with fMRI on an associative learning task in 28 male human participants to characterize the effect of the prior belief of tactile events on connections mediating the outcome of perceptual decisions. Activity in anterior insular cortex (AIC), premotor cortex (PMd), and inferior parietal lobule (IPL) were modulated by prior belief on unexpected targets compared with expected targets. On expected targets, prior belief decreased the connection strength from AIC to IPL, whereas it increased the connection strength from AIC to PMd when targets were unexpected. Individual differences in the modulatory strength of prior belief on insular projections correlated with the precision that increases the influence of prediction errors on belief updating. These results suggest complementary effects of prior belief on insular-frontoparietal projections mediating the precision of prediction during probabilistic tactile learning.SIGNIFICANCE STATEMENT In a probabilistic environment, the prior belief of sensory events can be inferred from past experiences. How this prior belief modulates effective brain connectivity for updating expectations for future decision-making remains unexplored. Combining hierarchical Bayesian modeling with fMRI, we show that during tactile associative learning, prior expectations modulate connections originating in the anterior insula cortex and targeting salience-related and attention-related frontoparietal areas (i.e., parietal and premotor cortex). These connections seem to be involved in updating evidence based on the precision of ascending inputs to guide future decision-making.

Neuroimaging premenstrual dysphoric disorder: A systematic and critical review

Endocrine organizational and activational influences on cognitive and affective circuits are likely critical to the development of premenstrual dysphoric disorder (PMDD), a sex-specific hormone-dependent mood disorder. An overview of the anatomical and functional neural characterization of this disorder is presented here by means of neuroimaging correlates, identified from eighteen publications (n = 361 subjects). While white matter integrity remains uninvestigated, greater cerebellar grey matter volume and metabolism were observed in patients with PMDD, along with altered serotonergic and GABAergic neurotransmission. Differential corticolimbic activation in response to emotional stimuli distinguishes the PMDD brain, namely enhanced amygdalar and diminished fronto-cortical function. Thus far, the emotional distress and dysregulation linked to PMDD seem to be defined by structural, chemical and functional brain signatures; however, their characterization remains sparsely studied and somewhat inconsistent. Clear and well-replicated neurobiological features of PMDD are needed to promote timely diagnoses and inform development of prevention and treatment strategies.

Confidence in Decision-Making during Probabilistic Tactile Learning Related to Distinct Thalamo–Prefrontal Pathways

The flexibility in adjusting the decision strategy from trial to trial is a prerequisite for learning in a probabilistic environment. Corresponding neural underpinnings remain largely unexplored. In the present study, 28 male humans were engaged in an associative learning task, in which they had to learn the changing probabilistic strengths of tactile sample stimuli. Combining functional magnetic resonance imaging with computational modeling, we show that an unchanged decision strategy over successively presented trials related to weakened functional connectivity between ventralmedial prefrontal cortex (vmPFC) and left secondary somatosensory cortex. The weaker the connection strength, the faster participants indicated their choice. If the decision strategy remained unchanged, participant’s decision confidence (i.e., prior belief) was related to functional connectivity between vmPFC and right pulvinar. While adjusting the decision strategy, we instead found confidence-related connections between left orbitofrontal cortex and left thalamic mediodorsal nucleus. The stronger the participant’s prior belief, the weaker the connection strengths. Together, these findings suggest that distinct thalamo–prefrontal pathways encode the confidence in keeping or changing the decision strategy during probabilistic learning. Low confidence in the decision strategy demands more thalamo–prefrontal processing resources, which is in-line with the theoretical accounts of the free-energy principle.

A brief guide to the menstrual cycle and oral contraceptive use for researchers in behavioral endocrinology

There is increasing evidence that reproductive hormones exert regulatory effects in the central nervous system that can influence behavioral, cognitive, perceptual, affective, and motivational processes. These effects occur in adults and post-pubertal individuals, and can be demonstrated in humans as well as laboratory animals. Large changes in 17β-estradiol and progesterone occur over the ovarian cycle (i.e., the menstrual cycle) and afford a way for researchers to explore the central nervous system (CNS) effects of these hormones under natural physiological conditions. Increasingly, oral contraceptives are also being studied, both as another route to understanding the CNS effects of reproductive hormones and also as pharmacological agents in their own right. This mini-review will summarize the basic physiology of the menstrual cycle and essential facts about oral contraceptives to help novice researchers to use both paradigms effectively.

The cycling brain: menstrual cycle related fluctuations in hippocampal and fronto-striatal activation and connectivity during cognitive tasks

Estradiol and progesterone vary along the menstrual cycle and exert opposite effects on a variety of neurotransmitter systems. However, few studies have addressed menstrual cycle-dependent changes in the brain. In the present study we investigate menstrual cycle changes in brain activation and connectivity patterns underlying cognition. Thirty-six naturally cycling women underwent functional MRI during two cognitive tasks: spatial navigation and verbal fluency. While no significant performance differences were observed along the menstrual cycle, the changes in brain activation patterns are strikingly similar during both tasks. Irrespective of the task, estradiol boosts hippocampal activation during the pre-ovulatory cycle phase and progesterone boosts fronto-striatal activation during the luteal cycle phase. Connectivity analyses suggest that the increase in right-hemispheric frontal activation is the result of inter-hemispheric decoupling and is involved in the down-regulation of hippocampal activation.

Do women expose themselves to more health-related risks in certain phases of the menstrual cycle? A meta-analytic review

Researchers have increasingly examined the menstrual cycle as a potential source of day-to-day variation in women's cognitions, motivations, and behavior. Within this literature, several lines of research have examined the impact of the menstrual cycle on women's engagement in activities that could negatively affect their health (alcohol and tobacco consumption, sexual behavior, risk recognition). However, findings have been mixed, leaving it unclear whether women may expose themselves to more health-related risks during certain phases of the cycle. We conducted a meta-analysis of 22 published and four unpublished studies (N = 7529, https://osf.io/xr37j/). The meta-analysis revealed shifts across the menstrual cycle in women's sexual behavior with others and risk recognition (higher in ovulatory phase), whereas there was no consistent pattern of difference for alcohol and cigarette consumption. These findings help to clarify the proximate physiological and evolutionary mechanisms underlying women's health-related risk-taking and may inform new interventions.

Individual differences in the effect of menstrual cycle on basal ganglia inhibitory control

Basal ganglia (BG) are involved in inhibitory control (IC) and known to change in structure and activation along the menstrual cycle. Therefore, we investigated BG activation and connectivity patterns related to IC during different cycle phases. Thirty-six naturally cycling women were scanned three times performing a Stop Signal Task and hormonal levels analysed from saliva samples. We found an impaired Stop signal reaction time (SSRT) during pre-ovulatory compared to menses the higher the baseline IC of women. Blood oxygen level dependent (BOLD)-response in bilateral putamen significantly decreased during the luteal phase. Connectivity strength from the left putamen displayed an interactive effect of cycle and IC. During pre-ovulatory the connectivity with anterior cingulate cortex and left inferior parietal lobe was significantly stronger the higher the IC, and during luteal with left supplementary motor area. Right putamen's activation and left hemisphere's connectivity predicted the SSRT across participants. Therefore, we propose a compensatory mechanism for the hormonal changes across the menstrual cycle based on a lateralized pattern.

Moderation of relation between psychological risk factors and alcohol use by sex

Alcohol consumption is a significant public health concern among young adults, with most recent research suggesting that the sex gap in alcohol consumption among young adults is closing. Thus, the present study tested sex as a moderator for known risk factors for alcohol use (impulsivity, sensation seeking, mindfulness). We examined sex differences by surveying young adults (n = 1,437) from across Washington state between 2011 and 2013 on alcohol risk factors (impulsivity, sensation seeking, mindfulness), alcohol consumption (quantity and frequency), and alcohol related negative consequences. Zero inflated Poisson and Zero inflated Negative Binomial models revealed that sex moderated the relationship between Peak Blood Alcohol Content (BAC) and impulsivity such that higher impulsivity was more strongly related to higher Peak BAC for women than for men. Overall, these results suggest that very few sex differences exist in alcohol consumption and alcohol-related negative consequences. Future research should look beyond the risk factors studied here to identify other important mechanisms that vary by sex that may be important targets for clinical or prevention efforts related to alcohol consumption.

The Effects of Menstrual Cycle Phase on Processing of Emotional Images

Abstract. The ovarian hormone levels can affect subjective ratings and modulate late positive potential (LPP) amplitudes evoked by images of varying appeal. The present study examines how different progesterone levels influence the valence, arousal ratings and mean LPP amplitudes evoked by pleasant, neutral, and unpleasant images. Twenty-three healthy females were grouped by menstrual cycle days (estradiol and progesterone levels): 10 were included in the follicular phase group and 13 were included in the luteal phase group. Each female rated the affective images in terms of valence and arousal while event-related potentials (ERPs) were measured. The valence ratings of pleasant images were higher in follicular phase group than in luteal, but the same effect was not seen in the arousal ratings. The arousal ratings to unpleasant images were higher than those to pleasant in luteal, but not in follicular phase group. However, the mean amplitude of the early LPP (450–700 ms) was significantly greater to pleasant than to neutral and unpleasant stimuli, but did not differ between follicular and luteal phase groups. The mean amplitude of the late LPP (700–950 ms) was significantly larger to pleasant and unpleasant compared to neutral images, but did not differ between menstrual cycle phase groups. Correlation analysis showed a significant negative relationship between progesterone levels and arousal ratings of pleasant and unpleasant images in luteal phase group. Arousal scores for unpleasant images negatively correlated with mean LPP amplitudes to unpleasant images at Pz site in the luteal phase group. The present study provides evidence that subjective ratings of affective images of different attractiveness could be influenced by female menstrual cycle phase, but mean amplitudes of LPP (450–950 ms) are not affected. However, results of correlational analysis suggest that valence, arousal ratings and mean LPP amplitudes are susceptible to the influence of hormone progesterone in luteal phase.

Influence of endogenous estradiol, progesterone, allopregnanolone, and dehydroepiandrosterone sulfate on brain resting state functional connectivity across the menstrual cycle

OBJECTIVE

To [1] study brain resting state functional connectivity (Rs-FC) in a well-characterized sample of healthy women in the mid-follicular and late luteal phases of the menstrual cycle; and [2] examine the correlation between endogenous E₂, P, allopregnanolone, and DHEAS and patterns of Rs-FC across the menstrual cycle.

DESIGN

We studied the Rs-FC of the default mode network, salience network, meso-paralimbic network, fronto-parietal network, visual network, and sensorimotor network in the mid-follicular and late luteal phases. Serum levels of E₂, P, allopregnanolone, and DHEAS were correlated to patterns of functional connectivity.

SETTING

University medical center.

PATIENT(S)

Twenty-five healthy women with regular menstrual cycles.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Functional connectivity of key brain networks at rest and correlations of hormones to Rs-FC in the mid-follcuar and late luteal menstrual phases.

RESULT(S)

There were no differences in Rs-FC between the mid-follicular and late luteal menstrual phases using either independent component analysis or seed-based analysis. However, specific correlations between each hormone and patterns of functional connectivity were found in both menstrual cycle phases.

CONCLUSION(S)

It seems that the association between female sex hormones and brain Rs-FC is menstrual cycle phase-dependent. Future studies should examine the cognitive and behavioral correlates of this association in regularly cycling women.

Interactive Effects of Dopamine Baseline Levels and Cycle Phase on Executive Functions: The Role of Progesterone

Estradiol and progesterone levels vary along the menstrual cycle and have multiple neuroactive effects, including on the dopaminergic system. Dopamine relates to executive functions in an “inverted U-shaped” manner and its levels are increased by estradiol. Accordingly, dopamine dependent changes in executive functions along the menstrual cycle have been previously studied in the pre-ovulatory phase, when estradiol levels peak. Specifically it has been demonstrated that working memory is enhanced during the pre-ovulatory phase in women with low dopamine baseline levels, but impaired in women with high dopamine baseline levels. However, the role of progesterone, which peaks in the luteal cycle phase, has not been taken into account previously. Therefore, the main goals of the present study were to extend these findings (i) to the luteal cycle phase and (ii) to other executive functions. Furthermore, the usefulness of the eye blink rate (EBR) as an indicator of dopamine baseline levels in menstrual cycle research was explored. 36 naturally cycling women were tested during three cycle phases (menses–low sex hormones; pre-ovulatory–high estradiol; luteal–high progesterone and estradiol). During each session, women performed a verbal N-back task, as measure of working memory, and a single trial version of the Stroop task, as measure of response inhibition and cognitive flexibility. Hormone levels were assessed from saliva samples and spontaneous eye blink rate was recorded during menses. In the N-back task, women were faster during the luteal phase the higher their progesterone levels, irrespective of their dopamine baseline levels. In the Stroop task, we found a dopamine-cycle interaction, which was also driven by the luteal phase and progesterone levels. For women with higher EBR performance decreased during the luteal phase, whereas for women with lower EBR performance improved during the luteal phase. These findings suggest an important role of progesterone in modulating dopamine-cycle interactions. Additionally, we identified the eye blink rate as a non-invasive indicator of baseline dopamine function in menstrual cycle research.

Crying, oral contraceptive use and the menstrual cycle

BACKGROUND

Crying, a complex neurobiological behavior with psychosocial and communication features, has been little studied in relationship to the menstrual cycle.

METHODS

In the Mood and Daily Life study (MiDL), a community sample of Canadian women aged 18-43 years, n=76, recorded crying proneness and crying frequency daily for six months along with menstrual cycle phase information.

RESULTS

Crying proneness was most likely during the premenstruum, a little less likely during menses and least likely during the mid-cycle phase, with statistically significant differences although the magnitude of these differences were small. By contrast, actual crying did not differ between the three menstrual cycle phases. Oral contraceptive use did not alter the relationship between menstrual cycle phase and either crying variable. A wide range of menstrual cycle phase - crying proneness patterns were seen with visual inspection of the individual women's line graphs.

LIMITATIONS

timing of ovulation was not ascertained. Using a three phase menstrual cycle division precluded separate late follicular and early luteal data analysis. The sample size was inadequate for a robust statistical test of actual crying.

CONCLUSIONS

reproductive aged women as a group report feeling more like crying premenstrually but may not actually cry more during this menstrual cycle phase. Individual patterns vary substantially. Oral contraceptive use did not affect these relationships. Suggestions for future research are included.

Estrogen- and progesterone-mediated structural neuroplasticity in women: evidence from neuroimaging

There is substantial evidence that the ovarian sex hormones, estrogen and progesterone, which vary considerably over the course of the human female lifetime, contribute to changes in brain structure and function. This structured, quantitative literature reviews aims to summarize neuroimaging literature addressing physiological variation in brain macro- and microstructure across an array of hormonal transitions including the menstrual cycle, use of hormonal contraceptives, pregnancy, and menopause. Twenty-five studies reporting structural neuroimaging of women, addressing variation across hormonal states, were identified from a structured search of PUBMED and were systematically reviewed. Although the studies are heterogenous with regard to methodology, overall the results point to overlapping areas of hormone related effects on brain structure particularly affecting the structures of the limbic system. These findings are in keeping with functional data that point to a role for estrogen and progesterone in mediating emotional processing.

Neuroimaging the Menstrual Cycle and Premenstrual Dysphoric Disorder

Knowledge of gonadal hormone-related influences on human brain anatomy, function, and chemistry is scarce. The present review scrutinized organizational and functional neuroimaging correlates of the menstrual cycle and premenstrual dysphoric disorder (PMDD). Supportive evidence of cyclic short-term structural and functional brain plasticity in response to gonadal hormonal modulation is provided. The paucity of studies, sparsity and discordance of findings, and weaknesses in study design at present hinder the drawing of firm conclusions. Ideal study designs should comprise high-resolution multimodal neuroimaging (e.g., MRI, DTI, rs-fMRI, fMRI, PET), hormones, genetic, and behavioral longitudinal assessments of healthy women and PMDD patients at critical time points of the menstrual cycle phase (i.e., early follicular phase, late follicular phase, mid-luteal phase) in a counter-balanced setup. Studies integrating large-scale brain network structural, functional, and molecular neuroimaging, as well as treatment data, will deepen the understanding of neural state, disorder, and treatment markers.

Anger in brain and body: the neural and physiological perturbation of decision-making by emotion

Emotion and cognition are dynamically coupled to bodily arousal: the induction of anger, even unconsciously, can reprioritise neural and physiological resources toward action states that bias cognitive processes. Here we examine behavioural, neural and bodily effects of covert anger processing and its influence on cognition, indexed by lexical decision-making. While recording beat-to-beat blood pressure, the words ANGER or RELAX were presented subliminally just prior to rapid word/non-word reaction-time judgements of letter-strings. Subliminal ANGER primes delayed the time taken to reach rapid lexical decisions, relative to RELAX primes. However, individuals with high trait anger were speeded up by subliminal anger primes. ANGER primes increased systolic blood pressure and the magnitude of this increase predicted reaction time prolongation. Within the brain, ANGER trials evoked an enhancement of activity within dorsal pons and an attenuation of activity within visual occipitotemporal and attentional parietal cortices. Activity within periaqueductal grey matter, occipital and parietal regions increased linearly with evoked blood pressure changes, indicating neural substrates through which covert anger impairs semantic decisions, putatively through its expression as visceral arousal. The behavioural and physiological impact of anger states compromises the efficiency of cognitive processing through action-ready changes in autonomic response that skew regional neural activity.

Menstrual cycle phase does not predict political conservatism

Recent authors have reported a relationship between women's fertility status, as indexed by menstrual cycle phase, and conservatism in moral, social and political values. We conducted a survey to test for the existence of a relationship between menstrual cycle day and conservatism. 2213 women reporting regular menstrual cycles provided data about their political views. Of these women, 2208 provided information about their cycle date, 1260 provided additional evidence of reliability in self-reported cycle date, and of these, 750 also indicated an absence of hormonal disruptors such as recent hormonal contraception use, breastfeeding or pregnancy. Cycle day was used to estimate day-specific fertility rate (probability of conception); political conservatism was measured via direct self-report and via responses to the "Moral Foundations" questionnaire. We also recorded relationship status, which has been reported to interact with menstrual cycle phase in determining political preferences. We found no evidence of a relationship between estimated cyclical fertility changes and conservatism, and no evidence of an interaction between relationship status and cyclical fertility in determining political attitudes. Our findings were robust to multiple inclusion/exclusion criteria and to different methods of estimating fertility and measuring conservatism. In summary, the relationship between cycle-linked reproductive parameters and conservatism may be weaker or less reliable than previously thought.

The neurobiology of emotion-cognition interactions: fundamental questions and strategies for future research

Recent years have witnessed the emergence of powerful new tools for assaying the brain and a remarkable acceleration of research focused on the interplay of emotion and cognition. This work has begun to yield new insights into fundamental questions about the nature of the mind and important clues about the origins of mental illness. In particular, this research demonstrates that stress, anxiety, and other kinds of emotion can profoundly influence key elements of cognition, including selective attention, working memory, and cognitive control. Often, this influence persists beyond the duration of transient emotional challenges, partially reflecting the slower molecular dynamics of catecholamine and hormonal neurochemistry. In turn, circuits involved in attention, executive control, and working memory contribute to the regulation of emotion. The distinction between the 'emotional' and the 'cognitive' brain is fuzzy and context-dependent. Indeed, there is compelling evidence that brain territories and psychological processes commonly associated with cognition, such as the dorsolateral prefrontal cortex and working memory, play a central role in emotion. Furthermore, putatively emotional and cognitive regions influence one another via a complex web of connections in ways that jointly contribute to adaptive and maladaptive behavior. This work demonstrates that emotion and cognition are deeply interwoven in the fabric of the brain, suggesting that widely held beliefs about the key constituents of 'the emotional brain' and 'the cognitive brain' are fundamentally flawed. We conclude by outlining several strategies for enhancing future research. Developing a deeper understanding of the emotional-cognitive brain is important, not just for understanding the mind but also for elucidating the root causes of its disorders.

Separate effects of sex hormones and sex chromosomes on brain structure and function revealed by high-resolution magnetic resonance imaging and spatial navigation assessment of the Four Core Genotype mouse model

Males and females exhibit several differences in brain structure and function. To examine the basis for these sex differences, we investigated the influences of sex hormones and sex chromosomes on brain structure and function in mice. We used the Four Core Genotype (4CG) mice, which can generate both male and female mice with XX or XY sex chromosome complement, allowing the decoupling of sex chromosomes from hormonal milieu. To examine whole brain structure, high-resolution ex vivo MRI was performed, and to assess differences in cognitive function, mice were trained on a radial arm maze. Voxel-wise and volumetric analyses of MRI data uncovered a striking independence of hormonal versus chromosomal influences in 30 sexually dimorphic brain regions. For example, the bed nucleus of the stria terminalis and the parieto-temporal lobe of the cerebral cortex displayed steroid-dependence while the cerebellar cortex, corpus callosum, and olfactory bulbs were influenced by sex chromosomes. Spatial learning and memory demonstrated strict hormone-dependency with no apparent influence of sex chromosomes. Understanding the influences of chromosomes and hormones on brain structure and function is important for understanding sex differences in brain structure and function, an endeavor that has eventual implications for understanding sex biases observed in the prevalence of psychiatric disorders.

Emotional and cognitive functional imaging of estrogen and progesterone effects in the female human brain: a systematic review

Ovarian hormones are pivotal for the physiological maintenance of the brain function as well as its response to environmental stimuli. There is mounting evidence attesting the relevance of endogenous ovarian hormones as well as exogenous estradiol and progesterone for emotional and cognitive processing. The present review systematically summarized current knowledge on sex steroid hormonal modulation of neural substrates of emotion and cognition revealed by functional magnetic resonance imaging (fMRI). Twenty-four studies of healthy naturally cycling and combined oral contraceptives (COC) user women, or women undergoing experimental manipulations, during their reproductive age, were included. Furthermore, six studies of premenstrual dysphoric disorder (PMDD), a hormonally based mood disorder, and three of gender dysphoria (GD), which provides an intriguing opportunity to examine the effect of high-dose cross-sex hormone therapy (CSHT) on brain functioning, were included. Globally, low (early follicular and the entire follicular phase for estrogen and progesterone, respectively) and high (COC, CSHT, late follicular and luteal phase for estrogen; COC, mid- and late-luteal phase for progesterone) hormonal milieu diversely affected the response of several brain regions including the amygdala, anterior cingulate cortex, and inferior frontal gyrus, but their functional recruitment across groups and domains was scattered. The constellation of findings provides initial evidence of the influence of sex steroid hormones on cortical and subcortical regions implicated in emotional and cognitive processing. Further well-powered and multimodal neuroimaging studies will be needed to identify the neural mechanism of functional brain alterations induced by sex steroid hormones.

Low levels of estradiol are associated with elevated conditioned responding during fear extinction and with intrusive memories in daily life

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Intrusive memories can be seen as conditioned responses to trauma reminders.

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Novel conditioned-intrusion paradigm models both fear conditioning and intrusions.

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Low estradiol is related to higher conditioned responses during fear extinction.

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Low estradiol is related to higher intrusive memory strength in daily life.

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Conditioned responding during extinction partially explains the latter relationship.

Posttraumatic stress disorder (PTSD) can be conceptualized as a disorder of emotional memory showing strong (conditioned) responses to trauma reminders and intrusive memories among other symptoms. Women are at greater risk of developing PTSD than men. Recent studies have demonstrated an influence of ovarian steroid hormones in both fear conditioning and intrusive memory paradigms. However, although intrusive memories are considered non-extinguished emotional reactions to trauma reminders, none of the previous studies has investigated effects of ovarian hormones on fear conditioning mechanisms and intrusive memories in conjunction. This may have contributed to an overall inconsistent picture of the role of these hormones in emotional learning and memory. To remedy this, we exposed 37 healthy women with a natural menstrual cycle (during early follicular or luteal cycle phase) to a novel conditioned-intrusion paradigm designed to model real-life traumatic experiences. The paradigm included a differential fear conditioning procedure with short violent film clips as unconditioned stimuli. Intrusive memories about the film clips were assessed ambulatorily on subsequent days. Women with lower levels of estradiol displayed elevated differential conditioned skin conductance responding during fear extinction and showed stronger intrusive memories. The inverse relationship between estradiol and intrusive memories was at least partially accounted for by the conditioned responding observed during fear extinction. Progesterone levels were not associated with either fear acquisition/extinction or with intrusive memories. This suggests that lower levels of estradiol might promote stronger symptoms of PTSD through associative processes.

Smoking improves divided attention in schizophrenia

RATIONALE

Smoking is highly prevalent in schizophrenia, and there is evidence for beneficial effects on neurocognition. Smoking is therefore hypothesized a self-medication in schizophrenia. Although much effort is devoted to characterize those cognitive domains that potentially benefit from smoking, divided attention has not yet been investigated.

OBJECTIVES

The aim of this study was to analyze the interactional effects of diagnosis of schizophrenia and smoking history on divided attention.

METHODS

We investigated behavioral measures of divided attention in a sample of 48 schizophrenic patients and 48 controls (24 current smokers and non-smokers each) carefully matched for age, sex, education, verbal IQ, and smoking status with general linear models.

RESULTS

Most important within the scope of this study, significant interactions were found for valid reactions and errors of omission: Performance substantially increased in smoking schizophrenic patients, but not in controls. Further, these interactions were modified by sex, driven by female schizophrenic patients who showed a significant behavioral advantage of smokers over non-smokers, other than male schizophrenic patients or healthy controls who did not express this sex-specific pattern.

CONCLUSIONS

Results suggest a positive effect of smoking history on divided attention in schizophrenic patients. This study provides first evidence that the complex attention domain of divided attention is improved by smoking, which further substantiates the self-medication hypothesis of smoking in schizophrenia, although this has been shown mainly for sustained and selective attention. Gender-specific effects on cognition need to be further investigated.