Threat directionality modulates defensive reactions in humans: cardiac and electrodermal responses.

Features of threatening cues and the associated context influence the perceived imminence of threat and the defensive responses evoked. To provide additional knowledge about how the directionality of a threat (i.e. directed-towards or away from the viewer) might impact defensive responses in humans, participants were shown pictures of a man carrying a gun (threat) or nonlethal object (neutral) directed-away from or towards the participant. Cardiac and electrodermal responses were collected. Compared to neutral images, threatening images depicting a gun directed-towards the participant induced sustained bradycardia and an increased electrodermal response, interpreted as immobility under attack. This defensive immobility reaction is evoked by high perceived threat and inescapable situations and indicates intense action preparation. Pictures of guns directed-away from the participant induced shorter bradycardia and no significant modulation of the electrodermal response compared to neutral pictures, which might be consistent with the perception of a less threatening situation. The results show that the directionality of threat stimuli is a key factor that prompts different patterns of defensive responses.

Impact of Loneliness on Training Gains with Heart Rate Variability Biofeedback in the Elderly: A Pilot Study.

The negative impact of loneliness on the health of the elderly is particularly noticeable because of the effects of central control on the autonomic nervous system. Such an impact can be assessed through heart rate variability (HRV) analysis and can be modified using HRV biofeedback training. This study aimed to investigate the impact of different levels of social interaction reported by the elderly on HRV before and after training with HRV biofeedback and after a follow-up period. The participants of this pilot study comprised 16 elderly people of both sexes with a mean age of 71.20 ± 4.92 years. The participants were divided into two groups, the loneliness group (N = 8) and the no-loneliness group (N = 8), based on a combination of both criteria: the institutionalization condition (institutionalized or not) and the score on the loneliness scale (high or low). All participants had their HRV components recorded at baseline, after 14 training sessions with HRV biofeedback (three times a week, 15 min each for 4.5 weeks), and after 4.5 weeks of follow-up without training. After HRV biofeedback training, HRV components increased in both groups. However, the gains lasted at follow-up only in the no-loneliness group. In conclusion, loneliness can influence the maintenance of HRV after interruption of training with HRV biofeedback in the elderly. HRV biofeedback training can be an innovative and effective tool for complementary treatment of elderly individuals, but its effects on lonely elderly individuals need to be further investigated.

Machine learning applied to fMRI patterns of brain activation in response to mutilation pictures predicts PTSD symptoms.

BACKGROUND: The present study aimed to apply multivariate pattern recognition methods to predict posttraumatic stress symptoms from whole-brain activation patterns during two contexts where the aversiveness of unpleasant pictures was manipulated by the presence or absence of safety cues. METHODS: Trauma-exposed participants were presented with neutral and mutilation pictures during functional magnetic resonance imaging (fMRI) collection. Before the presentation of pictures, a text informed the subjects that the pictures were fictitious ("safe context") or real-life scenes ("real context"). We trained machine learning regression models (Gaussian process regression (GPR)) to predict PTSD symptoms in real and safe contexts. RESULTS: The GPR model could predict PTSD symptoms from brain responses to mutilation pictures in the real context but not in the safe context. The brain regions with the highest contribution to the model were the occipito-parietal regions, including the superior parietal gyrus, inferior parietal gyrus, and supramarginal gyrus. Additional analysis showed that GPR regression models accurately predicted clusters of PTSD symptoms, nominal intrusion, avoidance, and alterations in cognition. As expected, we obtained very similar results as those obtained in a model predicting PTSD total symptoms. CONCLUSION: This study is the first to show that machine learning applied to fMRI data collected in an aversive context can predict not only PTSD total symptoms but also clusters of PTSD symptoms in a more aversive context. Furthermore, this approach was able to identify potential biomarkers for PTSD, especially in occipitoparietal regions.

Long-term benefits of heart rate variability biofeedback training in older adults with different levels of social interaction: a pilot study.

To test whether heart rate variability (HRV) biofeedback training benefits older adults with different social interaction levels. METHODS: 32 older adults (16 were institutionalized and 16 were not). Both groups received 14 sessions, 15 min, 3 times a week, with half of the individuals receiving HRV biofeedback training and the other half receiving control training. The following parameters were assessed immediately before and after training, and 4.5 weeks after the last session (follow-up period): aerobic conditioning, anthropometric data, emotional scores, and HRV components. RESULTS: Before the training, the institutionalized individuals had higher scores of loneliness (p < 0.01) and depression (p < 0.0001) and lower social touches (p < 0.0001), body mass (p = 0.04), and body fat percentage (p = 0.002) than the non-institutionalized individuals. HRV biofeedback improved symptoms of depression in both groups. HRV improved only in the non-institutionalized group, and loneliness only in the institutionalized group. Lastly, all changes persisted after the follow-up period. CONCLUSIONS: HRV biofeedback training was effective in improving symptoms of depression in older adults. Improvement of HRV and loneliness was dependent on the level of social interaction.

Stuck in a Moment: Tonic Immobility Predicts Poor Quality of Life in Treated PTSD Patients.

BACKGROUND: Posttraumatic stress disorder (PTSD) is a prevalent and disabling multisystem disorder, with significant physical and psychiatric morbidity and poor quality of life (QOL). Although peritraumatic reactions - tonic immobility and dissociation - are established predictors of PTSD severity and development, there is a dearth of investigation assessing the impact of peritraumatic reactions on QOL of PTSD patients. Quality of life has become increasingly important in health care and research as a reliable outcome measure. It comprises psychological, physical, social and environmental domains, providing important information about the impact of diseases on patient's life. This study aims to investigate the impact of peritraumatic tonic immobility and peritraumatic dissociation on QOL of PTSD civilian outpatients. SUBJECTS AND METHODS: It is a cross-sectional study of 50 victims of urban violence with current PTSD, recruited in a specialized outpatient clinic. Instruments used were: Structured Clinical Interview IV, Peritraumatic Dissociative Experiences Questionnaire, Tonic Immobility Scale and WHOQOL-BREF (psychological, physical, social and environmental domains). Linear regression models were fitted to evaluate the impact of peritraumatic reactions - tonic immobility and dissociation - on WHOQOL-BREF scores. We controlled for sex as potential confounding. RESULTS: The severity of peritraumatic tonic immobility negatively impacted on psychological and environment domains of quality of life. For each additional point on the Tonic Immobility Scale, there was a decreased of 0.8 points on the scores of these domains of WHOQOL-BREF. Neither the peritraumatic reactions showed effects on physical nor social domains. Possible limitations of this study include cross-sectional design, relatively small sample size of tertiary center outpatients and recall bias. CONCLUSIONS: Peritraumatic tonic immobility is related to poor quality of life, adding new insights about the relationship between this immobility reaction and PTSD.

Tonic immobility is associated with posttraumatic stress symptoms in healthcare professionals exposed to COVID-19-related trauma.

The Coronavirus Disease 2019 (COVID-19) pandemic has exposed healthcare workers (HCW) to traumatic situations that might lead to the development of posttraumatic stress disorder (PTSD). An important vulnerability factor for PTSD is the peritraumatic tonic immobility (TI) reaction, an involuntary and reflexive defensive response evoked by an intense and inescapable threat. TI is largely understudied in humans and has not been investigated during trauma related to COVID-19. For HCW, the pandemic context might be experienced as an intense and potentially inescapable threat, i.e., an overwhelming situation. Here, we investigated if TI response occurred during traumatic events related to the pandemic and its association with posttraumatic stress symptoms (PTSS). An online survey of 1001 HCW investigated COVID-19-related traumatic experiences, TI and PTSS. TI was reported for all types of traumatic events, and multivariate regression models revealed that TI was significantly associated with PTSS severity. HCW who reported high TI scores exhibited an increase of 9.08 times the probability of having a probable diagnosis of PTSD. Thus, TI was evoked by pandemic-related traumatic situations and associated with PTSS severity and higher odds of a PTSD diagnosis. Tonic immobility occurrence should be screened, and psychoeducation about its reflexive biological nature should be introduced.

Decreased self-reported receiving of social touch and social support predict loneliness in healthy adults.

Loneliness has emerged as a public health concern. Previous research has reported its deleterious effects on physical and mental health; however, some specific psychophysiological mechanisms in healthy adults remain to be elucidated. The aim of the current study is to investigate whether self-reported social support and social touch (giving and receiving social touch), as well as resting heart rate variability (HRV), are significant negative predictors of loneliness in healthy adults. The study sample consists of 120 healthy students (50% female) with a mean age of 21.85 years old (DP= 2.21). The students were asked to complete a psychiatric screening questionnaire utilizing loneliness, social support, and social touch scales. HRV was derived from an electrocardiographic signal recorded for 15 min, with the participant relaxed in a supine position. Linear regression analyses were conducted to evaluate loneliness as a function of social support, social touch (giving or receiving touch), and resting HRV. The results show that social support (p< 0.001) and social touch, specifically receiving touch (p< 0.002), accounted for a significant proportion of the variance in loneliness. However, neither giving touch nor resting HRV was a significant predictor of loneliness. The current study highlights specific psychosocial factors in healthy adults that should be considered as promising pathways in order to reduce or work toward preventing loneliness, thus promoting better health and well-being.

Visuo-Motor Affective Interplay: Bonding Scenes Promote Implicit Motor Pre-dispositions Associated With Social Grooming-A Pilot Study.

Proximity and interpersonal contact are prominent components of social connection. Giving affective touch to others is fundamental for human bonding. This brief report presents preliminary results from a pilot study. It explores if exposure to bonding scenes impacts the activity of specific muscles related to physical interaction. Fingers flexion is a very important component when performing most actions of affectionate contact. We explored the visuo-motor affective interplay by priming participants with bonding scenes and assessing the electromyographic activity of the fingers flexor muscle, in the absence of any overt movements. Photographs of dyads in social interaction and of the same dyads not interacting were employed. We examined the effects upon the electromyographical activity: (i) during the passive exposure to pictures, and (ii) during picture offset and when expecting the signal to perform a fingers flexion task. Interacting dyads compared to matched non-interacting dyads increased electromyographic activity of the fingers flexor muscle in both contexts. Specific capture of visual bonding cues at the level of visual cortex had been described in the literature. Here we showed that the neural processing of visual bonding cues reaches the fingers flexor muscle. Besides, previous visualization of bonding cues enhanced background electromyographic activity during motor preparation to perform the fingers flexion task, which might reflect a sustained leakage of central motor activity downstream leading to increase in firing of the respective motor neurons. These data suggest, at the effector level, an implicit visuo-motor connection in which social interaction cues evoke intrinsic dispositions toward affectionate social behavior.

Decreased self-reported receiving of social touch and social support predict loneliness in healthy adults

ABSTRACT Loneliness has emerged as a public health concern. Previous research has reported its deleterious effects on physical and mental health; however, some specific psychophysiological mechanisms in healthy adults remain to be elucidated. The aim of the current study is to investigate whether self-reported social support and social touch (giving and receiving social touch), as well as resting heart rate variability (HRV), are significant negative predictors of loneliness in healthy adults. The study sample consists of 120 healthy students (50% female) with a mean age of 21.85 years old (DP= 2.21). The students were asked to complete a psychiatric screening questionnaire utilizing loneliness, social support, and social touch scales. HRV was derived from an electrocardiographic signal recorded for 15 min, with the participant relaxed in a supine position. Linear regression analyses were conducted to evaluate loneliness as a function of social support, social touch (giving or receiving touch), and resting HRV. The results show that social support (p< 0.001) and social touch, specifically receiving touch (p< 0.002), accounted for a significant proportion of the variance in loneliness. However, neither giving touch nor resting HRV was a significant predictor of loneliness. The current study highlights specific psychosocial factors in healthy adults that should be considered as promising pathways in order to reduce or work toward preventing loneliness, thus promoting better health and well-being.

Tonic Immobility is Associated with PTSD Symptoms in Traumatized Adolescents.

PURPOSE: Growing evidence suggests that peritraumatic tonic immobility, an involuntary defensive response that involves extreme physical immobility and the perceived inability to escape, is a significant predictor of post-traumatic stress disorder (PTSD) symptomatology. However, this issue has not been specifically addressed in adolescents. Here, we investigated whether tonic immobility response experienced during the worst childhood or adolescent trauma is associated with PTSD symptom severity in a non-clinical student sample. METHODS: The sample was composed of students in 9th grade who were attending public and private schools. Symptoms of post-traumatic stress and tonic immobility were assessed using questionnaires. We performed bivariate and multivariate negative binomial regressions to examine whether tonic immobility was associated with PTSD symptomatology after controlling for confounders (peritraumatic dissociation, peritraumatic panic reactions, gender, age and time since trauma). RESULTS: We found an association between tonic immobility and PTSD symptom severity, even after controlling for confounders. Therefore, tonic immobility is associated with PTSD symptoms in trauma-exposed adolescents. CONCLUSION: These findings highlight tonic immobility as a possible risk factor that could be used to provide direction for more targeted trauma interventions for individuals, particularly those at risk for developing PTSD. Therefore, it contributes to preventing and reducing the psychiatric burden in adolescence and later in life.

Facing Racism and Sexism in Science by Fighting Against Social Implicit Bias: A Latina and Black Woman's Perspective.

The editors of several major journals have recently asserted the importance of combating racism and sexism in science. This is especially relevant now, as the COVID-19 pandemic may have led to a widening of the gender and racial/ethnicity gaps. Implicit bias is a crucial component in this fight. Negative stereotypes that are socially constructed in a given culture are frequently associated with implicit bias (which is unconscious or not perceived). In the present article, we point to scientific evidence that shows the presence of implicit bias in the academic community, contributing to strongly damaging unconscious evaluations and judgments of individuals or groups. Additionally, we suggest several actions aimed at (1) editors and reviewers of scientific journals (2) people in positions of power within funding agencies and research institutions, and (3) members of selection committees to mitigate this effect. These recommendations are based on the experience of a group of Latinx American scientists comprising Black and Latina women, teachers, and undergraduate students who participate in women in science working group at universities in the state of Rio de Janeiro, Brazil. With this article, we hope to contribute to reflections, actions, and the development of institutional policies that enable and consolidate diversity in science and reduce disparities based on gender and race/ethnicity.

Unveiling the neural underpinnings of optimism: a systematic review.

Optimism is a personality trait strongly associated with physical and psychological well-being, with correlates in nonhuman species. Optimistic individuals hold positive expectancies for their future, have better physical and psychological health, recover faster after heart disease and other ailments, and cope more effectively with stress and anxiety. We performed a systematic review of neuroimaging studies focusing on neural correlates of optimism. A search identified 14 papers eligible for inclusion. Two key brain areas were linked to optimism: the anterior cingulate cortex (ACC), involved in imagining the future and processing of self-referential information; and the inferior frontal gyrus (IFG), involved in response inhibition and processing relevant cues. ACC activity was positively correlated with trait optimism and with the probability estimations of future positive events. Behavioral measures of optimistic tendencies investigated through the belief update task correlated positively with IFG activity. Elucidating the neural underpinnings of optimism may inform both the development of prevention and treatment strategies for several mental disorders negatively associated with optimism, such as depression, as well as help to foster new resilience promotion interventions targeting healthy, vulnerable, and mentally ill individuals.

A Systematic Review of Electrophysiological Findings in Binge-Purge Eating Disorders: A Window Into Brain Dynamics.

Binge-purge eating disorders (BP-ED), such as bulimia nervosa and binge eating disorder, may share some neurobiological features. Electroencephalography (EEG) is a non-invasive measurement modality that may aid in research and diagnosis of BP-ED. We conducted a systematic review of the literature on EEG findings in BP-ED, seeking to summarize and analyze the current evidence, as well as identify shortcomings and gaps to inform new perspectives for future studies. Following PRISMA Statement recommendations, the PubMed, Embase, and Web of Science databases were searched using terms related to "electroencephalography" and "binge-purge" eating disorders. Of 555 articles retrieved, 15 met predefined inclusion criteria and were included for full-text analysis. Eleven studies investigated EEG by means of event-related potentials (ERP) in BP-ED individuals: 7 using eating disorder-related stimuli (i.e., food, body image) and 4 using non-eating disorder-related stimuli (i.e., facial expressions or auditory clicks). These studies found significant differences in the N200, P200, P300, and LPP components in BP-ED participants compared to controls, indicating that this population exhibits impairments in selective attention, attentional allocation/processing, and allocation of motivational or emotion-based attention. Five studies investigated EEG using frequency analysis; reporting significant differences in beta activity in fronto-temporal and occipito-temporo-parietal areas in BP-ED individuals compared to controls, revealing a dysfunctional brain network. However, the small number of studies, the heterogeneity of samples, study paradigms, stimulus types, and the lack of an adequate assessment of neuropsychological parameters are some limitations of the current literature. Although some EEG data are promising and consistent with neuroimaging and neuropsychological findings in individuals with BP-ED, future studies need to overcome current methodological shortcomings.

The invisible scars of emotional abuse: a common and highly harmful form of childhood maltreatment.

BACKGROUND: Childhood maltreatment (CM) is unfortunately widespread globally and has been linked with an increased risk of a variety of psychiatric disorders in adults, including posttraumatic stress disorder (PTSD). These associations are well established in the literature for some maltreatment forms, such as sexual and physical abuse. However, the effects of emotional maltreatment are much less explored, even though this type figures among the most common forms of childhood maltreatment. Thus, the present study aims to investigate the impact of each type of childhood maltreatment, both individually and conjointly, on revictimization and PTSD symptom severity using a nonclinical college student sample. METHODS: Five hundred and two graduate and undergraduate students participated in the study by completing questionnaires assessing lifetime traumatic experiences in general, maltreatment during childhood and PTSD symptoms. Bivariate and multivariate negative binomial regressions were applied to examine the associations among childhood maltreatment, revictimization, and PTSD symptom severity. RESULTS: Our results showed that using bivariate models, all types of CM were significantly associated with revictimization and PTSD symptom severity. Multivariate models showed that emotional abuse was the type of maltreatment associated with the highest incidence rates of revictimization and PTSD symptom severity. CONCLUSIONS: These data provide additional evidence of the harmful effects of childhood maltreatment and its long-term consequences for individuals' mental health. Notably, the findings highlight the importance of studying the impacts of emotional abuse, which seems to be a highly prevalent, understudied, and chronic form of maltreatment that is as toxic as other maltreatment forms.

Pictures of social interaction prompt a sustained increase of the smile expression and induce sociability.

Viewing pictures of social interaction can facilitate approach behaviors. We conducted two studies to investigate if social interaction cues, empathy, and/or social touch modulate facial electromyographic (EMG) reactivity (as evidenced by the zygomaticus major and corrugator supercilii muscles) and mood states. We presented bonding pictures (depicting social interaction) and control pictures (without social interaction) while continuously recording zygomatic and corrugator EMG activities. In both studies, picture blocks were paired by valence and arousal. All participants were college students. In study 1, participants (n = 80, 47 women) read relevant priming texts immediately before viewing each block of 14 pictures. In study 2, participants did not read (n = 82, 63 women) priming texts before each block of 28 pictures. In study 1 and study 2, participants also completed mood states questionnaires to assess sociability and altruistic behavior. Empathy and social touch frequency were also assessed by self-reported questionnaires. In both studies, bonding pictures increased the zygomatic activity and the self-reported sociability feeling compared to control pictures. Only in study 2, bonding pictures decreased median corrugator activity compared to control pictures. We concluded that social interaction cues were efficient to increase sociability and prompt a sustained smile expression regardless of priming texts.

Vulnerability and Protective Factors for PTSD and Depression Symptoms Among Healthcare Workers During COVID-19: A Machine Learning Approach.

Background: Healthcare workers are at high risk for developing mental health problems during the COVID-19 pandemic. There is an urgent need to identify vulnerability and protective factors related to the severity of psychiatric symptoms among healthcare workers to implement targeted prevention and intervention programs to reduce the mental health burden worldwide during COVID-19. Objective: The present study aimed to apply a machine learning approach to predict depression and PTSD symptoms based on psychometric questions that assessed: (1) the level of stress due to being isolated from one's family; (2) professional recognition before and during the pandemic; and (3) altruistic acceptance of risk during the COVID-19 pandemic among healthcare workers. Methods: A total of 437 healthcare workers who experienced some level of isolation at the time of the pandemic participated in the study. Data were collected using a web survey conducted between June 12, 2020, and September 19, 2020. We trained two regression models to predict PTSD and depression symptoms. Pattern regression analyses consisted of a linear epsilon-insensitive support vector machine (ε-SVM). Predicted and actual clinical scores were compared using Pearson's correlation coefficient (r), the coefficient of determination (r2), and the normalized mean squared error (NMSE) to evaluate the model performance. A permutation test was applied to estimate significance levels. Results: Results were significant using two different cross-validation strategies to significantly decode both PTSD and depression symptoms. For all of the models, the stress due to social isolation and professional recognition were the variables with the greatest contributions to the predictive function. Interestingly, professional recognition had a negative predictive value, indicating an inverse relationship with PTSD and depression symptoms. Conclusions: Our findings emphasize the protective role of professional recognition and the vulnerability role of the level of stress due to social isolation in the severity of posttraumatic stress and depression symptoms. The insights gleaned from the current study will advance efforts in terms of intervention programs and public health messaging.

Hidden wounds of violence: Abnormal motor oscillatory brain activity is related to posttraumatic stress symptoms.

Victims of urban violence are at risk of developing Posttraumatic Stress Disorder (PTSD), one of the most debilitating consequences of violence. Considering that PTSD may be associated with inefficient selection of defensive responses, it is important to understand the relation between motor processing and PTSD. The present study aims to investigate the extent to which the severity of posttraumatic stress symptoms (PTSS) is related to motor preparation against visual threat cues in victims of urban violence. Participants performed a choice reaction time task while ignoring a picture that could be threating or neutral. The EEG indices extracted were the motor-related amplitude asymmetry (MRAA) in the alpha frequency range, and the lateralized readiness potential (LRP). We observed a linear relation between longer LRP latency and a slower reaction time, selectively during threat processing (compared to neutral) in low PTSS, but not in high PTSS participants. Alpha MRAA suppression and the PTSS were also linearly related: the smaller the alpha MRAA suppression in the threat condition relative to neutral, the greater the PTSS. These results provide evidence that threatening cues affect motor processing that is modulated by the severity of PTSS in victims of urban violence.

Correction to: How do you perceive threat? It's all in your pattern of brain activity.

The author found a mistake in their published article. They observed that Fig. 2 presented some mistakes as follow.

Interactions between emotion and action in the brain.

A growing literature supports the existence of interactions between emotion and action in the brain, and the central participation of the anterior midcingulate cortex (aMCC) in this regard. In the present functional magnetic resonance imaging study, we sought to investigate the role of self-relevance during such interactions by varying the context in which threating pictures were presented (with guns pointed towards or away from the observer). Participants performed a simple visual detection task following exposure to such stimuli. Except for voxelwise tests, we adopted a Bayesian analysis framework which evaluated evidence for the hypotheses of interest, given the data, in a continuous fashion. Behaviorally, our results demonstrated a valence by context interaction such that there was a tendency of speeding up responses to targets after viewing threat pictures directed towards the participant. In the brain, interaction patterns that paralleled those observed behaviorally were observed most notably in the middle temporal gyrus, supplementary motor area, precentral gyrus, and anterior insula. In these regions, activity was overall greater during threat conditions relative to neutral ones, and this effect was enhanced in the directed towards context. A valence by context interaction was observed in the aMCC too, where we also observed a correlation (across participants) of evoked responses and reaction time data. Taken together, our study revealed the context-sensitive engagement of motor-related areas during emotional perception, thus supporting the idea that emotion and action interact in important ways in the brain.

Association between habitual use of coping strategies and posttraumatic stress symptoms in a non-clinical sample of college students: A Bayesian approach.

The present study investigated the influences of coping styles on posttraumatic stress symptoms (PTSS) among a sample of non-clinical college students who were exposed to traumatic events. Ninety-nine college students participated in the study. However, the sample used in the analyses consisted of only 37 participants who fulfilled the DSM-IV criterion A for Posttraumatic Stress Disorder (PTSD) diagnosis. The PTSD Checklist-Civilian Version (PCL-C) and the Brief COPE were used to assess the participants' PTSS and habitual use of coping strategies, respectively. Bayesian and frequentist correlations showed that emotion-focused coping style was negatively associated with PTSS, while dysfunctional coping style was positively related to PTSS. In the subsequent linear regression on both statistical framework, dysfunctional coping was the only consistent variable predicting more PTSD symptoms. The findings presented here show that lower use of adaptive coping (emotion-focused) and higher use of dysfunctional coping styles on a daily basis are associated to PTSS severity in a non-clinical sample of college students. According to the Bayesian approach, which permits more generalization of data, dysfunctional coping style is determinant to higher levels of PTSS. These findings add new data to the body of research that highlight the critical role of distinct coping strategies in the severity of PTSS.