Gender differences in the cortical electrophysiological processing of visual emotional stimuli

Network analysis of misophonia symptoms using the Duke Misophonia Questionnaire

BACKGROUND

Misophonia is a complex disorder characterized by a strong aversion to specific sounds, leading to significant distress and impairment. While the Duke Misophonia Questionnaire (DMQ) is one of the most comprehensive and validated measures for assessing misophonia, the relative importance of specific subscales and items within the DMQ remains unclear. Network analysis enables an understanding of the interconnections among subscales, providing insights into which parts of the measure are most central to the others. This study employed network analysis to examine the interconnections among DMQ subscales and identify the most central components of misophonia symptomatology.

METHODS

Network analysis was conducted on DMQ data from 144 adults with varying levels of misophonia symptoms. Four network models were examined: overall misophonia, symptoms, beliefs, and impairment. Sex differences were also explored.

RESULTS

The Impairment subscale emerged as the most central in the overall network for both males and females. Key items included cognitive reactions ("I need to get away from the sound," "I thought about physically hurting the person making the sound") as well as affective reactions (panic, anger) in the symptom sub-network, non-acceptance of misophonia beliefs ("I hate being like this") in the belief sub-network, and deterioration of self-esteem due to misophonia in the impairment sub-network. Females reported more severe cognitive and physiological symptoms than males.

CONCLUSIONS

The DMQ Impairment subscale and specific items identified as most central in each network may represent key aspects of misophonia symptomatology. Prioritizing these components in assessment and intervention efforts may be beneficial when appropriate.

Associations between attentional biases for emotional images and rumination in depression

Rumination is a key feature of depression and contributes to its onset, maintenance, and recurrence. Researchers have proposed that biases in the attentional processing of emotional information may underlie rumination, and particularly, the brooding component. This investigation evaluated associations between attentional biases for emotional images and rumination, including both brooding and reflection, in currently and never depressed participants. In two separate studies, participants viewed sets of four emotional images (happy, sad, threatening, and neutral) for 8 s in a free-viewing eye-tracking paradigm. In both studies, currently depressed individuals attended to happy face images and happy naturalistic images significantly less than never depressed individuals. In Study 2, currently depressed individuals attended to sad naturalistic images significantly more than never depressed individuals. There were no statistically significant associations between attentional biases and any of the forms of rumination, independent of their shared relationship with depression symptoms. These findings call into question the robustness of the link between attentional biases and rumination.

Negative affective priming: Reliability and associations with depression symptoms in three samples

The negative affective priming (NAP) task is a behavioral measure of inhibition of emotional stimuli. Previous studies using the NAP task have found that individuals with depression show reduced inhibition of negative stimuli, suggesting that inhibition biases may play a role in the etiology and maintenance of depression. However, the psychometric properties of the NAP task have not been evaluated or reported. In the present study, we report data on the association between NAP task performance and depression symptoms in three independent samples, and we evaluate the internal consistency and test-retest reliability of the NAP effect indices. The NAP effect for both negative and positive target words had poor internal consistency in all three samples, as well as poor 2-week (Study 2) and 6-month (Study 3) test-retest reliability. The internal consistency and test-retest reliability of response times (RT) for the individual trial types were moderate to high, as were the intercorrelations between trial types. This pattern of results indicates that overall RT is reliable but variance in RTs for the different trial types in the NAP task is indistinguishable from variance in overall RT. Depression symptom severity was not associated with the NAP effect for negative or positive target words in any of the samples, which could be due to the poor reliability of the NAP effect. Based on these findings, we do not recommend that researchers use the NAP task as a measure of individual differences in the inhibition of emotional stimuli.

Gender effect in affective processing: Alpha EEG source analysis on emotional slides and film-clips

Past research on gender-related brain asymmetries in emotions was limited and not univocal. The present study analyzed EEG alpha activity (indexing cortical de-activation) from 64 scalp sites in 20 women and 20 men during a counterbalanced block presentation of emotional slides and short video-clips. Stimuli consisted of 45 brief clips of 13 s, divided into 15 erotic (pleasant), 15 neutral and 15 fear (unpleasant) contents. Slides consisted in 45 photo shots (presented for 13 s each) extracted from the videos. As expected, women perceived fear stimuli as more arousing and more unpleasant compared to men. Alpha EEG source analysis revealed gender effects depending on stimulus. Emotional film-clips elicited in both groups a pattern of greater right than left occipital activation. Instead, emotional pictures activated opposite occipital regions, as women showed greater activation in the left, men in the right hemisphere. Men also showed greater activation to Erotic compared to Fear stimuli (i.e., pictures/clips) in the posterior parietal complex. Results point to the relevance of emotional stimulus type to reveal gender effects: clips are ecological, dynamic and engaging, and forced a unified pattern of emotional responses that reset individual differences. Emotional pictures, less engaging, allowed individual differences to emerge and interact with the stimulus category.

The influence of imagery vividness and internally-directed attention on the neural mechanisms underlying the encoding of visual mental images into episodic memory

Attention can be directed externally toward sensory information or internally toward self-generated information. Using electroencephalography (EEG), we investigated the attentional processes underlying the formation and encoding of self-generated mental images into episodic memory. Participants viewed flickering words referring to common objects and were tasked with forming visual mental images of the objects and rating their vividness. Subsequent memory for the presented object words was assessed using an old-new recognition task. Internally-directed attention during image generation was indexed as a reduction in steady-state visual evoked potentials (SSVEPs), oscillatory EEG responses at the frequency of a flickering stimulus. The results yielded 3 main findings. First, SSVEP power driven by the flickering word stimuli decreased as subjects directed attention internally to form the corresponding mental image. Second, SSVEP power returned to pre-imagery baseline more slowly for low- than high-vividness later remembered items, suggesting that longer internally-directed attention is required to generate subsequently remembered low-vividness images. Finally, the event-related-potential difference due to memory was more sustained for subsequently remembered low- versus high-vividness items, suggesting that additional conceptual processing may have been needed to remember the low-vividness visual images. Taken together, the results clarify the neural mechanisms supporting the encoding of self-generated information.

Neuroelectric Correlates of Human Sexuality: A Review and Meta-Analysis

Many reviews on sexual arousal in humans focus on different brain imaging methods and behavioral observations. Although neurotransmission in the brain is mainly performed through electrochemical signals, there are no systematic reviews of the electrophysiological correlates of sexual arousal. We performed a systematic search on this subject and reviewed 255 studies including various electrophysiological methods. Our results show how neuroelectric signals have been used to investigate genital somatotopy as well as basic genital physiology during sexual arousal and how cortical electric signals have been recorded during orgasm. Moreover, experiments on the interactions of cognition and sexual arousal in healthy subjects and in individuals with abnormal sexual preferences were analyzed as well as case studies on sexual disturbances associated with diseases of the nervous system. In addition, 25 studies focusing on brain potentials during the interaction of cognition and sexual arousal were eligible for meta-analysis. The results showed significant effect sizes for specific brain potentials during sexual stimulation (P3: Cohen's d = 1.82, N = 300, LPP: Cohen's d = 2.30, N = 510) with high heterogeneity between the combined studies. Taken together, our review shows how neuroelectric methods can consistently differentiate sexual arousal from other emotional states.

Well under control: Control demand changes are sufficient for metacontrol

Metacontrol arises from the efficient retrieval of cognitive control by environmental cues that are predictive of the upcoming control demands. Previous studies have demonstrated that proactive and reactive metacontrol can be indexed by a list-wide switch probability (LWSP) and an item-specific switch probability (ISSP) effect, respectively. However, what triggers metacontrol in the first place has not been clearly articulated. While a "mere-experience" hypothesis attributes metacontrol to changes in control demands, an "affective-signaling" hypothesis suggests that high control demands are aversive and aversiveness drives metacontrol. In two experiments, we adjudicated between these hypotheses by considering the modes of metacontrol (proactive vs. reactive) and temporal dynamics of background valence (sustained vs. transient and positive vs. negative). We induced metacontrol (proactive or reactive) in a task-switching paradigm and created background valence by using positive and negative images as stimuli. With valence being an irrelevant aspect of the task, the design allows us to test whether (task-irrelevant) background valence would modulate metacontrol. While we were able to replicate the LWSP effect in Experiment 1 and the ISSP effect in Experiment 2, we did not find valence modulating either effect, regardless of the background valence being a sustained (Experiment 1) or a transient one (Experiment 2). These findings together suggest that negative valence (i.e., aversiveness) does not necessarily benefit metacontrol, and control demand variations are sufficient to induce metacontrol.

Internet Addiction among Young Adult University Students during the COVID-19 Pandemic: The Role of Peritraumatic Distress, Attachment, and Alexithymia

The literature focused on the effect of the COVID-19 pandemic on young adult university students' mental health shows a significant increase in psychopathological symptoms and Internet Addiction (IA). The key role played by attachment and alexithymia has also been suggested, but no study has explored the possible dynamic relationship between these variables. We recruited a sample of n = 410 young adult university students online. We assessed the attachment to parents and peers (through IPPA), alexithymia (through TAS-20), peritraumatic distress symptoms due to COVID-19 (through CPDI), and IA (through IAT). The results showed that the relationship between the attachment to mothers and IA was partially mediated by alexithymia and by the serial mediation of alexithymia and peritraumatic distress, whereas the influence of the attachment to fathers on IA was fully mediated by peritraumatic distress. The direct effects of the attachment to peers on alexithymia, peritraumatic distress, and IA were all significant, as were the indirect paths via the simple mediation of both alexithymia and peritraumatic distress and the multiple serial mediation of alexithymia and peritraumatic distress. Our findings suggested that the relationship between attachment, alexithymia, and psychopathological risk is dynamic in predicting IA during the pandemic among young adult university students and that the different attachment figures exert a peculiar contribution to these processes.

Effects of a three-week executive control training on adaptation to task difficulty and emotional interference

Intact executive functions are characterized by flexible adaptation to task requirements, while these effects are reduced in internalizing disorders. Furthermore, as executive functions play an important role in emotion regulation, deficits in executive functions may contribute to symptom generation in psychological disorders through increased emotional interference. Thus, the present study investigated transfer effects of a three-week executive control training on adaptation to task difficulty and emotional interference in healthy participants (n = 24) to further explore the training's suitability for clinical application. To assess the adaptation to task difficulty, the proportion congruency effect on behavioral data (response times, error rates) and ERP measures (N2, CRN) was assessed in a flanker task with varying frequency of incompatible trials (25%, 75%). To quantify emotional interference, flanker stimuli were superimposed on neutral or negative pictures. Replicating previous results, the training increased interference control as indexed by decreased response times and errors rates, increased N2 amplitude and decreased CRN amplitude in incompatible trials after training. Proportion congruency effects were weaker than expected and not affected by the training intervention. The training lead to a shift in the time-point of emotional interference: before training negative pictures lead to a reduction in CRN amplitude, while after training this reduction was observed for the N2. This pattern illustrates that the training leads to a change in task processing mode from predominant response-related cognitive control to predominant stimulus-related cognitive control (N2), indicating a proactive processing mode.

Coherence of attention and memory biases in currently and previously depressed women

Previous research has found that depression is characterised by biased processing of emotional information. Although most studies have examined cognitive biases in isolation, simultaneous examination of multiple biases is required to understand how they may interact and influence one another to produce depression vulnerability. In this study, the attention and memory biases of currently depressed, previously depressed, and never depressed women were examined using the same stimuli and a unified methodology. Participants viewed negative, positive, and neutral words while their eye gaze was tracked and recorded. After a distraction task, participants completed an incidental recognition test that included words from the eye-tracking task and new words. The results supported the hypothesised mediation model for positive words: currently depressed women had a reduced attention bias for positive words and, in turn, had poorer memory for positive words relative to never depressed women. Previously depressed women, however, showed a lack of coherence between attention and memory biases for positive words. The groups did not differ in their attention or memory biases for negative words. The findings provide novel evidence in support of a causal link between the absence of protective attention and memory biases for positive information in clinical depression.

Childhood maltreatment experiences and emotion perception in young Chinese adults: Sex as a moderator

Men and women seem to perceive and react differently to emotional stimuli and have different susceptibilities to childhood trauma. With a cross-sectional design, this study aimed to investigate whether specific patterns of childhood-maltreatment experiences are associated with specific patterns of emotion perception and the sex differences in this relationship. A total of 173 adults rated valence, arousal, and dominance for 60 pictures (varying in pleasantness, unpleasantness, and neutral emotion) from the International Affective Picture System and completed the Childhood Trauma Questionnaire-Short Form. Using a partial least squares (PLS) regression analysis, after controlling for depressive and anxious states, recent stressful life events, personality, and cognitive reappraisal strategy, we identified a profile (linear combination) of childhood-maltreatment experiences (emotional neglect, physical neglect, and physical abuse) that was associated with a profile of emotion-perception dimensions (perceiving negative visual stimuli as more unpleasant and subservient, positive stimuli as more pleasant and dominant, and neutral stimuli as more arousing). This association pattern was significant only for the male participants. Hence, our findings suggest that childhood maltreatment might make men more "emotional" in their adulthood. The impact of this childhood-maltreatment-associated alteration in emotion perception on male mental health needs further investigation.

Unpleasant Pictures Exposure Evokes Different Repercussion on Emotional State and Heart Rate Response in Healthy Women and Men

To evaluate the heart rate response, emotion and changes in anxiety and anger levels after exposure to unpleasant pictures from the International Assessment Pictures System (IAPS) compared with neutral picture exposure in healthy individuals. Forty participants (23 women) visited the laboratory on two occasions. State anger and state anxiety levels were evaluated pre- and post-visualization of a set of IAPS pictures and heart rate was monitored during exposure. Two different picture sets were utilized-one with neutral pictures (that served as the control) and the other with unpleasant pictures. State anxiety and state anger were higher in post-unpleasant session for women than before (p < 0.001). For men, only state anxiety was higher in the post-unpleasant session (p < 0.001). State anxiety (p = 0.004) and state anger (p < 0.001) post-unpleasant session was higher for women than in men. The pleasure and dominance domains were lower in the unpleasant session for both men and women (p < 0.001), and the arousal domain was higher for both men and women (p < 0.001) than in the neutral session. In the unpleasant session, arousal was higher (p = 0.004), and dominance was lower (p < 0.001) among women than among men, but no difference in pleasure was found (p > 0.05). For women, average heart rate was higher on unpleasant session, compared to neutral (p = 0.01), but not for men (p > 0.05). Women are more sensitive and react strongly to unpleasant picture exposure. The IAPS unpleasant session was not able to induce anger levels in men.

An fNIRS Investigation of Masculinity, Femininity, and Sex on Nonparents' Empathic Response to Infant Cries

According to societal stereotypes, the female sex and people who are more feminine have been considered to be more empathic than males and people who are more masculine. Therefore, females and feminine individuals are expected to respond more empathically to an infant's cries. While this hypothesis was tested using self-report scales, it has not been explored thoroughly in terms of prefrontal cortex (PFC) activity, which may be a more objective means of measuring empathy. Specifically, the medial PFC (mPFC) is involved in social cognitive processing and thus a good proxy to measure the level of empathy. This study aims to (1) assess if the empathic response, in terms of medial PFC (mPFC) activity, to infant cries differ between sexes; (2) investigate if the empathic response is moderated by levels of masculinity and femininity. Functional near-infrared spectroscopy (fNIRS) was used to measure nonparent participants' (18 males, 20 females) mPFC response to infant cries of different pitches (high and low). The Toronto Empathy Questionnaire was used to measure trait empathy and Bem's Sex Role Inventory was used to measure the level of masculinity and femininity. Results revealed that biological sex had no significant effect on the empathic response towards infant cries of varying pitch. Furthermore, masculinity, not femininity, was correlated with an increase in empathic response in the mPFC to high but not low-pitch infant cries. We reason that this is because of the higher aversiveness and inflicted pain associated with higher-pitched cries, which induces more emotional and physical pain that masculine individuals seek to avoid. Overall, the results suggest that greater masculinity would imply greater mentalizing and processing of empathy-related information.

A New Multidimensional Questionnaire of Empathy for Early and Middle Adolescents in Spanish

The aim of this study was to develop a Multidimensional Questionnaire of Empathy for Adolescents, since a model of cognitive social neuroscience, operationalizing the dimensions of emotional contagion, self-awareness, perspective-taking, emotional regulation, and empathic attitude. For the psychometric study of the instrument, 320 young adolescents in school participated, from both genders (125 male, 195 female), aged 13 to 16 (M = 14.23; SD = .95). The discriminant power of the items was evaluated, as well as the underlying structure of the instrument, its internal consistency, and different evidences of external, convergent, discriminant, and group-comparison validity. The results indicated that all the items were discriminative. The adjustment indexes of confirmatory factorial analysis allowed confirming the pentafactorial structure of the scale, consisting of 15 items. The internal consistency indexes of the different dimensions were between moderate and adequate. Likewise, differences in empathy between men and women were analyzed, the results of which indicated differences in favor of women. The different collected evidences of validity were consistent with what was expected theoretically. In this way it is possible to conclude that this Multidimensional Empathy Questionnaire for Adolescents (CMEA) is a valid and reliable measure for the evaluation of empathy in adolescents.

Video‐triggered EEG‐emotion public databases and current methods: A survey

Emotions, formed in the process of perceiving external environment, directly affect human daily life, such as social interaction, work efficiency, physical wellness, and mental health. In recent decades, emotion recognition has become a promising research direction with significant application values. Taking the advantages of electroencephalogram (EEG) signals (i.e., high time resolution) and video‐based external emotion evoking (i.e., rich media information), video‐triggered emotion recognition with EEG signals has been proven as a useful tool to conduct emotion‐related studies in a laboratory environment, which provides constructive technical supports for establishing real‐time emotion interaction systems. In this paper, we will focus on video‐triggered EEG‐based emotion recognition and present a systematical introduction of the current available video‐triggered EEG‐based emotion databases with the corresponding analysis methods. First, current video‐triggered EEG databases for emotion recognition (e.g., DEAP, MAHNOB‐HCI, SEED series databases) will be presented with full details. Then, the commonly used EEG feature extraction, feature selection, and modeling methods in video‐triggered EEG‐based emotion recognition will be systematically summarized and a brief review of current situation about video‐triggered EEG‐based emotion studies will be provided. Finally, the limitations and possible prospects of the existing video‐triggered EEG‐emotion databases will be fully discussed.

Mediating Effect of Perceived Stress on the Association between Physical Activity and Sleep Quality among Chinese College Students

BACKGROUND

While physical activity has been reported to positively affect stress and sleep quality, less is known about the potential relationships among them. The present study aimed to investigate the mediating effect of stress on the association between physical activity and sleep quality in Chinese college students, after controlling for age, nationality, and tobacco and alcohol use.

PARTICIPANTS

The sample comprised 6973 college students representing three Chinese universities.

METHODS

Physical activity, perceived stress, and sleep quality were respectively measured using the International Physical Activity Questionnaire-Short Form (IPAQ-SF), Perceived Stress Scale-10 Items (PSS-10), and Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Mediating effects of perceived stress on the association between physical activity and sleep quality were observed in males and females, with 42.4% (partial mediating effect) and 306.3% (complete mediating effect) as percentages of mediation, respectively.

CONCLUSION

The results of this study may provide some suggestions that physical activity could improve sleep by aiding individuals in coping with stress and indicate that stress management might be an effective non-pharmaceutical therapy for sleep improvement.

Neuroimmune Mechanisms and Sex/Gender-Dependent Effects in the Pathophysiology of Mental Disorders

Innate and adaptive immune mechanisms have emerged as critical regulators of CNS homeostasis and mental health. A plethora of immunologic factors have been reported to interact with emotion- and behavior-related neuronal circuits, modulating susceptibility and resilience to mental disorders. However, it remains unclear whether immune dysregulation is a cardinal causal factor or an outcome of the pathologies associated with mental disorders. Emerging variations in immune regulatory pathways based on sex differences provide an additional framework for discussion in these psychiatric disorders. In this review, we present the current literature pertaining to the effects that disrupted immune pathways have in mental disorder pathophysiology, including immune dysregulation in CNS and periphery, microglial activation, and disturbances of the blood-brain barrier. In addition, we present the suggested origins of such immune dysregulation and discuss the gender and sex influence of the neuroimmune substrates that contribute to mental disorders. The findings challenge the conventional view of these disorders and open the window to a diverse spectrum of innovative therapeutic targets that focus on the immune-specific pathophenotypes in neuronal circuits and behavior. SIGNIFICANCE STATEMENT: The involvement of gender-dependent inflammatory mechanisms on the development of mental pathologies is gaining momentum. This review addresses these novel factors and presents the accumulating evidence introducing microglia and proinflammatory elements as critical components and potential targets for the treatment of mental disorders.

Conceptual Closure Elicited by Event Boundary Transitions Affects Commercial Communication Effectiveness

While our experience of the world may appear continuous, recent evidence suggests that our experience is automatically segmented and encoded into long-term memory as a set of discrete events. Event segmentation is an important process in long-term memory encoding with evidence pointing to experiences occurring around event boundaries being better recognized subsequently. Neuroimaging studies have shown increased activity in the hippocampus and other nodes of the default mode network (DMN) when encountering an event boundary. We have previously demonstrated that the steady state topography (SST) measure of brain activity at a left inferior frontal scalp sites is correlated with the strength of long-term memory encoding. More recently, we have noted that event boundaries occurring in naturalistic stimuli such as television advertising trigger a transient drop in activity at the inferior frontal scalp sites, an effect we have termed Conceptual Closure. In this study, SST measures of brain activity were recorded in 50 male participants as they viewed a first-person journey through a 10-room virtual art gallery. We hypothesized that the transition from one room to another would serve as an event boundary which would triggers increased hippocampal and DMN activity while correspondingly decreasing activity in task positive networks in the vicinity of the inferior frontal cortex thus eliciting Conceptual Closure. A permutation test confirmed the hypothesis in that the appearance of the door between gallery rooms was associated with Conceptual Closure in that we observed a significant drop in brain activity at the left hemisphere inferior frontal scalp site at this point in time. Finally, we illustrate the real-world impact of Conceptual Closure by considering the commercial effectiveness of a television advertisement that exhibited Conceptual Closure at points of branding. The television advertisement was broadcast before and after it was re-edited to minimize Conceptual Closure at the time the advertising brand was being featured. Minimizing Conceptual Closure at the time of branding and key message was associated with significant increased commercial effectiveness of the advertisement.

Spatiotemporal Analysis of Event-related Current Density Reveals Dissociable Effects of Arousal and Valence on Emotional Picture Processing

BACKGROUND

The processing of emotional visual stimulation involves the processing of emotional and visuoperceptual information. It is not completely revealed how the valence and arousal affect these two aspects. The objective was to investigate the effects of valence and arousal on spatiotemporal characteristics of cortical information processing using distributed source imaging of event-related current density (ERCD).

METHODS

Electroencephalograms (64 channels) were recorded from 19 healthy men while presenting affective pictures. Distributed source localization analysis was adopted to obtain the spatiotemporal pattern of ERCD on cortical surface in response to emotional visual stimulation. A nonparametric cluster-based permutation test was used to find meaningful time and space without prior knowledge.

RESULTS

Significant changes of ERCD in 400-800 ms among positive, negative, and neutral emotional conditions were found in left posterior cingulate cortex (PCC) and right inferior temporal cortex (ITC). In the PCC, the stimuli with higher arousal levels showed more negative ERCD than neutral stimuli. In the ITC, the ERCD for negative stimuli was significantly more negative than those of positive and neutral ones.

CONCLUSION

Arousal and valence had strong influence on memory encoding and visual analysis at late period. The location and time showing significant change in neural activity according to arousal and valence would provide valuable information for understanding the changes of cortical function by neuropsychiatric disorders.

Emotional interference under low versus high executive control

Previous research has demonstrated that task-irrelevant emotional distractors interfere with task performance especially under low phasic executive control (i.e., in nonconflict trials). In the present study, we measured medio-frontal ERPs (N2 and correct-related negativity, CRN) to elucidate which aspects of task performance are affected by emotional interference in a flanker task. To create emotional interference, negative and neutral pictures were presented during the flanker stimuli. N2 and CRN were reduced after negative pictures, indicating that conflict processing and performance monitoring are both affected by emotional interference. On the behavioral level, prolonged response times after negative pictures were observed under low phasic executive control (i.e., in compatible trials). Additionally, we explored whether emotional interference is modulated not only by phasic changes in executive control (i.e., conflict vs. nonconflict trials) but also by tonic changes in executive control (i.e., low vs. high overall conflict frequency). To this end, the flanker task consisted of two blocks with 25% versus 75% incompatible trials. Prolonged response times after negative pictures in compatible trials were observed only under low tonic executive control but not under high executive control.

Sex differences and the neurobiology of affective disorders

Observations of the disproportionate incidence of depression in women compared with men have long preceded the recent explosion of interest in sex differences. Nonetheless, the source and implications of this epidemiologic sex difference remain unclear, as does the practical significance of the multitude of sex differences that have been reported in brain structure and function. In this article, we attempt to provide a framework for thinking about how sex and reproductive hormones (particularly estradiol as an example) might contribute to affective illness. After briefly reviewing some observed sex differences in depression, we discuss how sex might alter brain function through hormonal effects (both organizational (programmed) and activational (acute)), sex chromosome effects, and the interaction of sex with the environment. We next review sex differences in the brain at the structural, cellular, and network levels. We then focus on how sex and reproductive hormones regulate systems implicated in the pathophysiology of depression, including neuroplasticity, genetic and neural networks, the stress axis, and immune function. Finally, we suggest several models that might explain a sex-dependent differential regulation of affect and susceptibility to affective illness. As a disclaimer, the studies cited in this review are not intended to be comprehensive but rather serve as examples of the multitude of levels at which sex and reproductive hormones regulate brain structure and function. As such and despite our current ignorance regarding both the ontogeny of affective illness and the impact of sex on that ontogeny, sex differences may provide a lens through which we may better view the mechanisms underlying affective regulation and dysfunction.

Behavioral inhibition system and self-esteem as mediators between shyness and social anxiety

Shyness has been demonstrated to be an important factor associating with social anxiety. However, it is less clear on the mechanisms responsible for such association. The aim of the present study was to examine whether behavioral inhibition system (BIS) and self-esteem mediated the relationship between shyness and social anxiety. A sample of 521 healthy volunteers in the age range of 18-25 years completed self-report measures of BIS, self-esteem, shyness and social anxiety. Our correlational analyses showed that shyness was positively associated with social anxiety, supporting the overlapping and continuum hypotheses. Furthermore, BIS was positively correlated with shyness and social anxiety while self-esteem was negatively related to them, indicating that BIS and self-esteem were different in the relation between shyness and social anxiety. Importantly, results from structural equation modeling revealed that the relation between shyness and social anxiety was partially mediated by BIS and self-esteem, which suggested that they might play important roles in the relation between shyness and social anxiety.

The impact of spoken action words on performance in a cross-modal oddball task

In this study a cross-modal oddball task was employed to study the effect that words spoken either non-urgently or urgently would have on a digit categorization task and if women would exhibit greater behavioral inhibitory control. The words were unrelated to the task itself, but related to the action required to complete the task. Forty participants (21 women) conducted a computerized categorization task while exposed to a sinewave tone as a standard stimulus (75% of the trials) or a to-be ignored word (press, stop) spoken either non-urgently or urgently as unexpected auditory deviant stimulus (6.25% trials for each category). Urgent words had sharp intonation and an average fundamental frequency (F₀) ranging from 191.9 (stop) to 204.6 (press) Hz. Non-urgent words had low intonation with average F₀ ranging from 103.9.9 (stop) to 120.3 (press) Hz. As expected, deviant distraction and longer response times were found by exposure to the word stop, but deviant distraction was not found to be significant with the word press or due to intonation. While the results showed that women had in general longer reaction times, there were no gender differences found related to the deviant distraction caused by word or intonation. The present results do not support the hypothesis that women have greater behavioral inhibitory control, but there was evidence that the meaning of the word could influence response times.

EVALUATION OF SIGNAL PROCESSING TECHNIQUES IN DISCRIMINATING ECG SIGNALS OF MEN AND WOMEN DURING REST CONDITION AND EMOTIONAL STATES

Great range of electrocardiogram (ECG) signal processing methods can be found in the literature. In addition, the importance of gender differences in physiological activities was also identified in various conditions. This article aims to provide a comprehensive evaluation of linear and nonlinear ECG parameters to indicate suitable signal processing approaches which can show significant differences between men and women. These differences were investigated in two conditions: (i) during rest condition, and (ii) during the affective image inducements. A wide range of parameters from time-, frequency-, wavelet-, and nonlinear-techniques were examined. Applying the Wilcoxon rank sum test, significant differences between two genders were inspected. The analysis was performed on 47 college students at rest condition and while subjects watching four types of affective pictures, including sadness, happiness, fear, and peacefulness. The impact of these emotions on the results was also investigated. The results indicated that 72.95% and 72.61% of all features were significantly different between male and female in rest condition and affective inducements, respectively. In addition, the highest percentage of the significant difference between ECG parameters of men and women was achieved using nonlinear characteristics. Considering all features together, the highest significant difference between two genders was achieved for negative emotions, including sadness and fear. In conclusion, the results of this study emphasized the importance of gender role in cardiac responses during rest condition and different emotional states. Since these gender differences are well manifested by nonlinear signal processing techniques, dynamical gender-specific ECG system may improve the automatic emotion recognition accuracies.

Sparse coding reveals greater functional connectivity in female brains during naturalistic emotional experience

Functional neuroimaging is widely used to examine changes in brain function associated with age, gender or neuropsychiatric conditions. FMRI (functional magnetic resonance imaging) studies employ either laboratory-designed tasks that engage the brain with abstracted and repeated stimuli, or resting state paradigms with little behavioral constraint. Recently, novel neuroimaging paradigms using naturalistic stimuli are gaining increasing attraction, as they offer an ecologically-valid condition to approximate brain function in real life. Wider application of naturalistic paradigms in exploring individual differences in brain function, however, awaits further advances in statistical methods for modeling dynamic and complex dataset. Here, we developed a novel data-driven strategy that employs group sparse representation to assess gender differences in brain responses during naturalistic emotional experience. Comparing to independent component analysis (ICA), sparse coding algorithm considers the intrinsic sparsity of neural coding and thus could be more suitable in modeling dynamic whole-brain fMRI signals. An online dictionary learning and sparse coding algorithm was applied to the aggregated fMRI signals from both groups, which was subsequently factorized into a common time series signal dictionary matrix and the associated weight coefficient matrix. Our results demonstrate that group sparse representation can effectively identify gender differences in functional brain network during natural viewing, with improved sensitivity and reliability over ICA-based method. Group sparse representation hence offers a superior data-driven strategy for examining brain function during naturalistic conditions, with great potential for clinical application in neuropsychiatric disorders.

Does Gender Matter in the Relationship between Anxiety and Decision-Making?

There is an ongoing debate about whether and how anxiety level affects behavioral performance in risk and/or ambiguous decision-making. According to the literature, we suggest that gender difference might be a confounding factor that has contributed to heterogeneous findings in previous studies. To examine this idea, 135 students who participated in this study were divided into six groups according to their gender (male/female) and trait anxiety level (high/medium/low; measured by the Trait form of Spielberger's State-Trait Anxiety Inventory). All groups finished the Iowa Gambling Task (IGT) for ambiguous decision-making, and the Game of Dice Task (GDT) for risk decision-making. Behavioral results revealed that the IGT but not the GDT showed an interaction between anxiety and gender. Specifically, men outperformed women in the IGT, but only when their trait anxiety levels were low. Meanwhile, the GDT showed a main effect of anxiety grouping, such that low anxious participants were more risk-seeking than their medium anxious counterparts. These findings indicate that gender selectively modulates the influence of anxiety on ambiguous decision-making, but not risk decision-making. The theoretical and practical implications of the current findings are discussed.

Are there age differences in attention to emotional images following a sad mood induction? Evidence from a free-viewing eye-tracking paradigm

Two experiments examined age differences in the effect of a sad mood induction (MI) on attention to emotional images. Younger and older adults viewed sets of four images while their eye gaze was tracked throughout an 8-s presentation. Images were viewed before and after a sad MI to assess the effect of a sad mood on attention to positive and negative scenes. Younger and older adults exhibited positively biased attention after the sad MI, significantly increasing their attention to positive images, with no evidence of an age difference in either experiment. A test of participants' recognition memory for the images indicated that the sad MI reduced memory accuracy for sad images for younger and older adults. The results suggest that heightened attention to positive images following a sad MI reflects an affect regulation strategy related to mood repair. The implications for theories of the positivity effect are discussed.

Sex differences in stress regulation of arousal and cognition

There are sex differences in the prevalence and presentation of many psychiatric disorders. For example, posttraumatic stress disorder (PTSD) and major depression are more common in women than men, and women with these disorders present with more hyperarousal symptoms than men. In contrast, attention deficit hyperactivity disorder (ADHD) and schizophrenia are more common in men than women, and men with these disorders have increased cognitive deficits compared to women. A shared feature of the aforementioned psychiatric disorders is the contribution of stressful events to their onset and/or severity. Here we propose that sex differences in stress responses bias females towards hyperarousal and males towards cognitive deficits. Evidence from clinical and preclinical studies is detailed. We also describe underlying neurobiological mechanisms. For example, sex differences in stress receptor signaling and trafficking in the locus coeruleus-arousal center are detailed. In learning circuits, evidence for sex differences in dendritic morphology is provided. Finally, we describe how evaluating sex-specific mechanisms for responding to stress in female and male rodents can lead to better treatments for stress-related psychiatric disorders.

Adaptation of the International Affective Picture System (IAPS) for European Portuguese

This study presents the results of the adaptation of the International Affective Picture System (IAPS) for European Portuguese (EP). Following the original procedure of Lang et al., 2000 native speakers of EP rated the 1,182 pictures of the last version of the IAPS set on the three affective dimensions of valence, arousal, and dominance, using the Self-Assessment Manikin (SAM). Results showed that the normative values of the IAPS for EP are properly distributed in the affective space of valence and arousal, showing the typical boomerang-shaped distribution observed in previous studies. Results also point to important differences in the way Portuguese females and males react to affective pictures that should be taken into consideration when planning and conducting research with Portuguese samples. Furthermore, the results from the cross-cultural comparisons between the EP ratings and the ratings from the American, Spanish, Brazilian, Belgian, Chilean, Indian, and Bosnian-Herzegovinian standardizations, showed that in spite of the fact that IAPS stimuli elicited affective responses that are similar across countries and cultures (at least in Western cultures), there are differences in the way Portuguese individuals react to IAPS pictures that strongly recommend the use of the normative values presented in this work. They can be downloaded as a supplemental archive at http://brm.psychonomic-journals.org/content/supplemental or at http://p-pal.di.uminho.pt/about/databases.

Impact of 5-HTTLPR on SSRI serotonin transporter blockade during emotion regulation: A preliminary fMRI study

BACKGROUND

The short ('S') allele of the serotonin transporter (5-HTT)-linked polymorphic region (5-HTTLPR) is associated with increased negative emotion processing bias, and this polymorphism moderates acute effects of selective serotonin reuptake inhibitor (SSRI) treatment. In this preliminary study, we explore the moderating effect of 5-HTTLPR on the impact of the SSRI, escitalopram during emotion regulation of negative emotional stimuli.

METHOD

Thirty-six healthy Caucasian, female participants underwent two fMRI scanning sessions following single dose escitalopram and placebo administration separated by a seven-day washout period according to a double-blind, randomized, placebo-controlled crossover design. Functional connectivity analysis was employed with a left (L) amygdala seed and a right interior frontal gyrus (R IFG) target.

RESULTS

Changes in functional connectivity with emotion regulation and treatment were linearly related to 5-HTTLPR 'L' allele load such that negative R IFG-L amygdala connectivity was increased with an increasing number of 'L' alleles. Therefore, escitalopram may facilitate the effects of reappraisal by enhancing negative functional connectivity, a finding that is greatest in participants homozygous for the 'L' allele and least in those homozygous for the 'S' allele.

LIMITATIONS

Sub-samples of the homozygote 'S/S' and 'L/L' 5-HTTLPR groupings were small. However, the within-subjects nature of the experiment and observing changes at the individual subject level increases our confidence in the findings of the present study.

CONCLUSIONS

The present study elucidates a potential neural mechanism by which antidepressant treatment produces differential treatment outcomes dependent on the 5-HTTLPR polymorphism, providing new and important leads for models of antidepressant action.

Roads Less Traveled: Sexual Dimorphism and Mast Cell Contributions to Migraine Pathology

Migraine is a common, little understood, and debilitating disease. It is much more prominent in women than in men (~2/3 are women) but the reasons for female preponderance are not clear. Migraineurs frequently experience severe comorbidities, such as allergies, depression, irritable bowel syndrome, and others; many of the comorbidities are more common in females. Current treatments for migraine are not gender specific, and rarely are migraine and its comorbidities considered and treated by the same specialist. Thus, migraine treatments represent a huge unmet medical need, which will only be addressed with greater understanding of its underlying pathophysiology. We discuss the current knowledge about sex differences in migraine and its comorbidities, and focus on the potential role of mast cells (MCs) in both. Sex-based differences in pain recognition and drug responses, fluid balance, and the blood–brain barrier are recognized but their impact on migraine is not well studied. Furthermore, MCs are well recognized for their prominent role in allergies but much less is known about their contributions to pain pathways in general and migraine specifically. MC-neuron bidirectional communication uniquely positions these cells as potential initiators and/or perpetuators of pain. MCs can secrete nociceptor sensitizing and activating agents, such as serotonin, prostaglandins, histamine, and proteolytic enzymes that can also activate the pain-mediating transient receptor potential vanilloid channels. MCs express receptors for both estrogen and progesterone that induce degranulation upon binding. Furthermore, environmental estrogens, such as Bisphenol A, activate MCs in preclinical models but their impact on pain pathways or migraine is understudied. We hope that this discussion will encourage scientists and physicians alike to bridge the knowledge gaps linking sex, MCs, and migraine to develop better, more comprehensive treatments for migraine patients.

Ratings for emotion film clips

Film clips are widely utilized to elicit emotion in a variety of research studies. Normative ratings for scenes selected for these purposes support the idea that selected clips correspond to the intended target emotion, but studies reporting normative ratings are limited. Using an ethnically diverse sample of college undergraduates, selected clips were rated for intensity, discreteness, valence, and arousal. Variables hypothesized to affect the perception of stimuli (i.e., gender, race-ethnicity, and familiarity) were also examined. Our analyses generally indicated that males reacted strongly to positively valenced film clips, whereas females reacted more strongly to negatively valenced film clips. Caucasian participants tended to react more strongly to the film clips, and we found some variation by race-ethnicity across target emotions. Finally, familiarity with the films tended to produce higher ratings for positively valenced film clips, and lower ratings for negatively valenced film clips. These findings provide normative ratings for a useful set of film clips for the study of emotion, and they underscore factors to be considered in research that utilizes scenes from film for emotion elicitation.

Gender differences in emotion experience perception under different facial muscle manipulations

According to embodied emotion theory, facial manipulations should modulate and initiate particular emotions. However, whether there are gender differences in emotion experience perception under different facial muscle manipulations is not clear. Therefore, we conducted two behavioral experiments to examine gender differences in emotional perception in response to facial expressions (sad, neutral, and happy) under three conditions: (1) holding a pen using only the teeth (HPT), which facilitates the muscles typically associated with smiling; (2) holding a pen using only the lips (HPL), which inhibits the muscles typically associated with smiling; and (3) a control condition--hold no pen (HNP). We found that HPT made the emotional feelings more positive, and that the change degree of female's ratings of sad facial expressions between conditions (HPL to HPT) was larger than males'. These results suggested cognition can be affected by the interaction of the stimuli and the body, especially the female.

Sexual and Non-Sexual Trauma, Depression and Self-Esteem in a Sample of Polish Women. A Cross-Sectional Study

The purpose of this research was to explore the issue of the psychological aftermaths of traumatic events in women. According to the existing body of evidence, women suffer more often than men from mental health problems as a result of a traumatic event-one of the explanations for this is that women experience sexual trauma more frequently and this type of trauma causes more severe negative consequences. Therefore, the main aim of this research was to compare the aftermaths of sexual and non-sexual traumatic events in women. Only traumatic events in adulthood were taken into consideration and were divided into two categories: recent events (previous two years) and those of an earlier occurrence. Depression and low level of self-esteem were included in the research model as possible consequences of traumatic events. A total of 273 women from Poland took part in a questionnaire survey. As hypothesized, in the case of recent events, participants who experienced a sexual trauma showed a higher level of depression and lower level of self-esteem compared with those subjects, who experienced a non-sexual trauma or did not experience a traumatic event at all. However, this effect was not observed in the case of events of earlier occurrence. Copyright © 2016 John Wiley & Sons, Ltd.

KEY PRACTITIONER MESSAGE

Relations between traumatic experiences and the level of depression and self-esteem in women were demonstrated. Women who experienced sexual trauma showed higher levels of depression and lower levels of self-esteem than women who experienced other types of trauma. Time of the occurrence of the traumatic events matters: the relations between traumatic events, depression and self-esteem were demonstrated in the case of the events that occurred within the last two years.

Temporal changes in attention to sad and happy faces distinguish currently and remitted depressed individuals from never depressed individuals

Depression is associated with attentional biases for emotional information that are proposed to reflect stable vulnerability factors for the development and recurrence of depression. A key question for researchers is whether those who have recovered from depression also exhibit attentional biases, and if so, how similar these biases are to those who are currently depressed. To address this question, the present study examined attention to emotional faces in remitted depressed (N=26), currently depressed (N=16), and never depressed (N=33) individuals. Participants viewed sets of four face images (happy, sad, threatening, and neutral) while their eye movements were tracked throughout an 8-s presentation. Like currently depressed participants, remitted depressed participants attended to sad faces significantly more than never depressed participants and attended to happy faces significantly less. Analyzing temporal changes in attention revealed that currently and remitted depressed participants did not reduce their attention to sad faces over the 8-s presentation, unlike never depressed participants. In contrast, remitted depressed participants attended to happy faces similarly to never depressed participants, increasing their attention to happy faces over the 8-s presentation. The implications for cognitive theories of depression and depression vulnerability are discussed.

Facilitation of emotion regulation with a single dose of escitalopram: A randomized fMRI study

Acute antidepressant administration modulates neural activity consistent with decreases in negative emotion processing bias. However, studies are yet to examine whether treatment facilitates neural activity during reappraisal, an adaptive emotion regulation strategy associated with behavioral treatment response. Here we examine the impact of acute administration on reappraisal of negative stimuli using pharmaco-fMRI. Thirty-six healthy female participants completed two sessions of fMRI scanning, separated by a one-week washout period. A single dose of the selective serotonin reuptake inhibitor, escitalopram (20mg) was administered to participants using a double-blind, randomized, placebo-controlled crossover design. When participants were administered escitalopram (relative to a placebo) and asked to reappraise negative emotional stimuli, left amygdala activation was decreased and right inferior frontal gyrus (R IFG) activation was increased. Also observed was a greater negative left amygdala-R IFG functional connectivity when participants were administered escitalopram relative to placebo, and this change in connectivity was associated with reductions in subjective ratings of valence and arousal of negative stimuli. Further analysis revealed connectivity modulation across multiple frontal regions. Results suggest that the acute effect of a commonly prescribed antidepressant may include facilitating the regulation of negative emotional stimuli, providing new important leads for models of antidepressant action.

Cognitive Bias by Gender Interaction on N170 Response to Emotional Facial Expressions in Major and Minor Depression

States of depression are considered to relate to a cognitive bias reactivity to emotional events. Moreover, gender effect may influence differences in emotional processing. The current study is to investigate whether there is an interaction of cognitive bias by gender on emotional processing in minor depression (MiD) and major depression (MaD). N170 component was obtained during a visual emotional oddball paradigm to manipulate the processing of emotional information in 33 MiD, 36 MaD, and 32 controls (CN). Compared with CN, in male, both MiD and MaD had lower N170 amplitudes for happy faces, but MaD had higher N170 amplitudes for sad faces; in female, both MiD and MaD had lower N170 amplitudes for happy and neutral faces, but higher N170 amplitudes for sad faces. Compared with MaD in male, MiD had higher N170 amplitudes for happy faces, lower N170 amplitudes for sad faces; in female, MiD only had higher N170 amplitudes for sad faces. Interestingly, a negative relationship was observed between N170 amplitude and the HDRS score for identification of happy faces in depressed patients while N170 amplitude was positively correlated with the HDRS score for sad faces identification. These results provide novel evidence for the mood-brightening effect with an interaction of cognitive bias by gender on emotional processing. It further suggests that female depression may be more vulnerable than male during emotional face processing with the unconscious negative cognitive bias and depressive syndromes may exist on a spectrum of severity on emotional face processing.

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS) and emotional processing - A behavioral and electrophysiological approach

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS) may have mood enhancement effects: higher DHEAS concentrations and DHEA/cortisol ratio have been related to lower depression scores and controlled trials of DHEA administration have reported significant antidepressant effects. The balance between DHEAS and DHEA has been suggested to influence brain functioning. We explored DHEAS, DHEA, cortisol, DHEA/cortisol and DHEAS/DHEA ratios relations to the processing of negative emotional stimuli at behavioral and brain levels by recording the electroencephalogram of 21 young women while performing a visual task with implicit neutral or negative emotional content in an audio-visual oddball paradigm. For each condition, salivary DHEA, DHEAS and cortisol were measured before performing the task and at 30 and 60min intervals. DHEA increased after task performance, independent of the implicit emotional content. With implicit negative emotion, higher DHEAS/DHEA and DHEA/cortisol ratios before task performance were related to shorter visual P300 latencies suggesting faster brain processing under a negative emotional context. In addition, higher DHEAS/DHEA ratios were related to reduced visual P300 amplitudes, indicating less processing of the negative emotional stimuli. With this study, we could show that at the electrophysiological level, higher DHEAS/DHEA and DHEA/cortisol ratios were related to shorter stimulus evaluation times suggesting less interference of the implicit negative content of the stimuli with the task. Furthermore, higher DHEAS/DHEA ratios were related to reduced processing of negative emotional stimuli which may eventually constitute a protective mechanism against negative information overload.

Emotional arousal modulation of right temporoparietal cortex in depression depends on parental depression status in women: first evidence

BACKGROUND

Structural and Electroencephalography (EEG) abnormalities in right temporoparietal cortex have been associated with family history of depression (FH). Here we investigate if functional abnormalities in this area, indexed by attenuated responses to emotionally arousing stimuli, are also family-history-dependent.

METHODS

Neuromagnetic activity for emotional and neutral complex scenes was recorded by Magnetoencephalography (MEG) in 20 depressed patients without, 8 depressed patients with FH, and 15 healthy controls. Emotion-sensitive neuronal steady state responses were cortical source localized and tested for group-by-emotion interactions.

RESULTS

The group-by-emotion interaction (F(4, 80)=4.4, p=0.004) was explained by a significant modulation of right temporoparietal cortex activity by emotional arousal in controls and patients without FH. This effect was reduced in FH positive patients. The difference between patient groups remained when clinical variables such as symptom severity were accounted for.

LIMITATIONS

All patients were medicated, but differences between patient groups remained after accounting for medication dosage. Further, the sample size was limited, but data-driven resampling statistics showed the robustness of our effects. Finally, the sample consists of female patients only and we cannot generalize our results to male samples.

CONCLUSIONS

Patients with FH show impaired recruitment of attention-relevant cortical circuitry by emotional stimuli. The neuroanatomical locus of this effect accords with previous reports on structural abnormalities and electrophysiological deficits at rest in individuals with FH. Our results speak to the relevance of right temporoparietal dysfunction in emotional information processing as a potential endophenotype for depression with FH.

Human sex differences in emotional processing of own-race and other-race faces

There is evidence that women and men show differences in the perception of affective facial expressions. However, none of the previous studies directly investigated sex differences in emotional processing of own-race and other-race faces. The current study addressed this issue using high time resolution event-related potential techniques. In total, data from 25 participants (13 women and 12 men) were analyzed. It was found that women showed increased N170 amplitudes to negative White faces compared with negative Chinese faces over the right hemisphere electrodes. This result suggests that women show enhanced sensitivity to other-race faces showing negative emotions (fear or disgust), which may contribute toward evolution. However, the current data showed that men had increased N170 amplitudes to happy Chinese versus happy White faces over the left hemisphere electrodes, indicating that men show enhanced sensitivity to own-race faces showing positive emotions (happiness). In this respect, men might use past pleasant emotional experiences to boost recognition of own-race faces.

The impact of 5-HTTLPR on acute serotonin transporter blockade by escitalopram on emotion processing: preliminary findings from a randomised, crossover fMRI study

OBJECTIVE

Benefit from antidepressant treatment such as selective serotonin reuptake inhibitors (SSRIs) may depend on individual differences in acute effects on neural emotion processing. The short ('S') allele of the serotonin transporter (5-HTT)-linked polymorphic region (5-HTTLPR) is associated with both negative emotion processing biases and poorer treatment outcomes. Therefore, the aim of the present study was to explore the effects of 5-HTTLPR on the impact of the SSRI escitalopram during processing of positive and negative emotional images, as well as neutral stimuli.

METHODS

The study employed a double-blind, randomised, placebo-controlled crossover design on 36 healthy Caucasian female participants who underwent functional magnetic resonance imaging (fMRI) scanning following placebo or escitalopram treatment, separated by a 7-day washout period.

RESULTS

Changes in the left amygdala signal with escitalopram treatment during processing of emotional stimuli were linearly related to the 5-HTTLPR 'S' allele load such that the signal to positive stimuli decreased and the signal to negative stimuli increased with an increasing number of low-expressing 'S' alleles. While 5-HTTLPR subgroups were small in size, individual subject changes with treatment and task condition increase confidence in the findings.

CONCLUSIONS

While preliminary, our findings comprise the first pharmacogenetic study demonstrating an effect of the 5-HTTLPR 'S' allele load on escitalopram-induced changes in amygdala activity during emotional processing, consistent with a 5-HTT expression dosage model. The present findings have implications for the impact of this polymorphism on antidepressant efficacy in patients with mood and anxiety disorders.

Snake fearfulness is associated with sustained competitive biases to visual snake features: hypervigilance without avoidance

The extent and time course of competition between a specific fear cue and task-related stimuli in early human visual cortex was investigated using electrophysiology. Steady-state visual evoked potentials (ssVEPs) were evoked using random-dot kinematograms that consisted of rapidly flickering (8.57 Hz) dots moving randomly, superimposed upon emotional or neutral distractor pictures. Participants were asked to detect intervals of coherently moving dots, ignoring the distractor pictures that varied in hedonic content. Women reporting high or low levels of snake fear were recruited from a large sample of healthy college students, and snake pictures served as fear-relevant distractors. The time-varying amplitude of the ssVEP evoked by the motion detection task showed significant reduction when viewing emotionally arousing, compared to neutral, distractors, replicating previous studies. For high-fear participants, snake distractors elicited a sustained attenuation of task evoked ssVEP amplitude, greater than the attenuation prompted by other unpleasant arousing content. These findings support a hypothesis that fear cues prompt sustained hypervigilance rather than perceptual avoidance.

Diminished emotion expressivity but not experience in men and women with schizophrenia

Prior studies indicate that men with schizophrenia are less outwardly expressive but report similar emotion experience as healthy people. However, it is unclear whether women with schizophrenia show this same disconnect between expressivity and experience. Men (n = 24) and women (n = 25) with schizophrenia or schizoaffective disorder and women without schizophrenia (n = 25) viewed emotionally evocative film clips and were video recorded to assess facial expressivity. Participants also reported their emotion experience after each clip. Men and women with schizophrenia did not significantly differ from one another in the frequency of facial expressions, but both groups exhibited fewer expressions than women without schizophrenia. People with schizophrenia also reported lower levels of trait expressivity compared with women without schizophrenia. Overall, people with schizophrenia did not differ from controls on self-reported emotion experience with one exception: Women with schizophrenia reported more unpleasant emotion than controls. These results indicate that both women and men with schizophrenia exhibit fewer outward expressions but experience comparable emotion experience as people without schizophrenia.

Impact of acute administration of escitalopram on the processing of emotional and neutral images: a randomized crossover fMRI study of healthy women

BACKGROUND

Acute neural effects of antidepressant medication on emotion processing biases may provide the foundation on which clinical outcomes are based. Along with effects on positive and negative stimuli, acute effects on neutral stimuli may also relate to antidepressant efficacy, yet these effects are still to be investigated. The present study therefore examined the impact of a single dose of the selective serotonin reuptake inhibitor escitalopram (20 mg) on positive, negative and neutral stimuli using pharmaco-fMRI.

METHODS

Within a double-blind, randomized, placebo-controlled crossover design, healthy women completed 2 sessions of treatment administration and fMRI scanning separated by a 1-week washout period.

RESULTS

We enrolled 36 women in our study. When participants were administered escitalopram relative to placebo, left amygdala activity was increased and right inferior frontal gyrus (IFG) activity was decreased during presentation of positive pictures (potentiation of positive emotion processing). In contrast, escitalopram was associated with decreased left amygdala and increased right IFG activity during presentation of negative pictures (attenuation of negative emotion processing). In addition, escitalopram decreased right IFG activity during the processing of neutral stimuli, akin to the effects on positive stimuli (decrease in negative appraisal).

LIMITATIONS

Although we used a women-only sample to reduce heterogeneity, our results may not generalize to men. Potential unblinding, which was related to the subjective occurrence of side effects, occurred in the study; however, manipulation check analyses demonstrated that results were not impacted.

CONCLUSION

These novel findings demonstrate that a single dose of the commonly prescribed escitalopram facilitates a positive information processing bias. These findings provide an important lead for better understanding effects of antidepressant medication.