Could Alcohol Abuse Drive Intimate Partner Violence Perpetrators' Psychophysiological Response to Acute Stress?

The contribution of brain volume to explain autonomous imbalance during recovery from acute stress in batterers

AIM

Many authors have suggested that intimate partner violence (IPV) perpetrators present an imbalance between both branches of the autonomous nervous system when coping with acute stress. Concretely, there is a predominance of the sympathetic branches over the parasympathetic ones when recovering from stress. This imbalance can be explained by their tendency toward anger rumination, and more concretely, by their focus on thoughts of revenge during this period. Unfortunately, there is a gap in the scientific literature in terms of using magnetic resonance imaging (MRI) techniques to assess which brain structures would explain this tendency of IPV perpetrators when coping with acute stress.

METHOD

The main objective of this study was to assess whether the gray matter volume (GMV) of relevant brain structures, signaled in previous scientific literature, moderates the association between thoughts of revenge and sympathetic activation during the recovery period, based on skin conductance levels (SCL) after being exposed to stress, in a group of IPV perpetrators (n = 58) and non-violent men (n = 61).

RESULTS

This study highlighted that the GMV of the left nucleus accumbens, right lobules of the cerebellum, and inferior temporal gyrus in IPV perpetrators moderated the association between thoughts of revenge and SCL during the recovery period. Accordingly, the higher the thoughts of revenge, the higher the sympathetic predominance (or higher SCL levels), especially among IPV perpetrators with the lowest GMV of these brain structures. Nonetheless, those variables were unrelated in the control group.

CONCLUSIONS

Our study highlights the involvement of certain brain structures and how they explain the tendency of some IPV perpetrators to ruminate anger or, more precisely, to focus on thoughts of revenge when they recover from acute stress. These results reinforce the need to incorporate neuroimaging techniques during screening processes to properly understand how IPV perpetrators deal with stress, which in turn helps target their needs and design concrete intervention modules.

Weakened sympathetic response and lower parasympathetic activity in intimate partner violence perpetrators when empathizing: Influence of autonomous activation in affective approach and prosocial behavior

The autonomic nervous system (ANS) functioning has been proposed as a relevant method to characterize the therapeutic needs of intimate partner violence (IPV) perpetrators. Nevertheless, research has neglected the influence of the ANS on socio-affective functions in this population. The aim of the present study was to analyze the psychophysiological activity of IPV perpetrators (n = 52) compared to controls (n = 46) following an empathic induction task, performed through negative emotion-eliciting videos. We employed two general ANS markers (heart rate [HR] and respiratory rate [RR]), two sympathetic-related indexes (pre-ejection period [PEP] and skin conductance level [SCL]) and a parasympathetic biomarker (respiratory sinus arrhythmia [RSA]). Additionally, we explored the impact of psychophysiological activity on prosocial behavior using Hare's donation procedure. Compared to controls, IPV perpetrators reported lower HR and SCL following the task, as well as longer PEP, suggesting an attenuated sympathetic response to others' distress. No differences in the RSA response pattern were found, however, IPV perpetrators displayed lower overall RSA levels throughout the protocol, indicative of reduced parasympathetic activity. Besides, while no differences in prosocial performance were observed, greater sympathetic responses and overall parasympathetic activity predicted increased donations across the sample. Thus, a high sympathetic and parasympathetic activity might influence the occurrence of prosocial behavior. The present study provides further evidence supporting that IPV perpetrators cope differently with others' negative emotions. In line with this biopsychosocial perspective, insights are gained on the emotional processing of IPV perpetrators which, in turn, could contribute to improve IPV psychotherapeutic programs.

Reduced vagal tone in intimate partner violence perpetrators is partly explained by anger rumination

Polyvagal theory proposed that an autonomous nervous system imbalance might be characteristic of violent individuals, especially reduced parasympathetic or vagal tone. Accordingly, some studies concluded that when intimate partner violence (IPV) perpetrators deal with acute stress, they tend to present a sympathetic predominance over the parasympathetic nervous system once the stress has ended. However, less is known about cognitive mechanisms that explain this phenomenon. In fact, this functioning might be explained by inner speech and/or angry thoughts (anger rumination) in reactive aggressors. Nonetheless, there is a gap in the scientific literature assessing whether this psychophysiological functioning in IPV perpetrators is explained by anger rumination. For this reason, the first aim of this study was to assess the cardiorespiratory (heart rate (HR), pre-ejection period (PEP), and respiratory sinus arrhythmia (RSA)) and electrodermal (skin conductance level (SCL)) changes, as well as the anger state, when coping with an acute laboratory stressor, comparing a group of reactive IPV perpetrators (n = 47) and a group of non-violent men (n = 36). The second aim was two-fold. After checking whether the groups differed on their anger rumination and manifestation of aggression (reactive and/or proactive) scores, we studied whether these variables explained psychophysiological and psychological responses to a laboratory task (changes and levels during the recovery period) in each group. Our results demonstrated that, compared to the control group, IPV perpetrators presented lower RSA levels (vagal tone). Even though the groups did not differ on their anger rumination or manifestation of aggression scores (except for proactive aggression), only in the IPV perpetrators, high anger rumination and reactive aggression partly explained the lower vagal tone (RSA levels) and high levels of anger state at post-task. Consequently, this study contributes to understanding the psychobiological basis for violence proneness in IPV perpetrators, making it possible to explore new therapeutic strategies.

Sympathetic Nervous System Predominance in Intimate Partner Violence Perpetrators After Coping With Acute Stress

It has been suggested that intimate partner violence (IPV) against women perpetrators present emotional dysregulations when dealing with acute stress, which in turn could help to explain their proneness to violence. Emotional regulation can be objectively measured by means of psychophysiological parameters/variables/indicators of autonomic nervous system (ANS) activity, such as cardiorespiratory (heart rate [HR], pre-ejection period [PEP] and respiratory sinus arrythmia [RSA]) and electrodermal (skin conductance levels [SCL]) signals. Therefore, this study aims to assess whether IPV perpetrators (n = 107) present differential psychophysiological and psychological state changes when coping with an acute cognitive laboratory stressor (a set of cognitive tests performed in front of an expert committee) in comparison with nonviolent men (n = 87). Moreover, the study assesses whether psychological state variables foster the psychophysiological response to acute stress. Our results demonstrate that, compared to nonviolent controls, IPV perpetrators showed higher HR and SCL values, shorter PEP, and lower RSA values during recovery from stress. They also presented higher negative affect (i.e., more anger and worse mood) after stress. Thus, high baseline anger explained the increases in emotional arousal when measured as SCL increases. The present study contributes evidence showing that IPV perpetrators and nonviolent men cope differently with stress. These findings might help forensic science to identify characteristics of violent individuals to establish their therapeutic needs. Furthermore, it would be appropriate to combine psychophysiological measurements with self-reports, thus increasing the reliability of the assessment of violent individuals.

Heart Rate and Skin Conductance Associations with Physical Aggression, Psychopathy, Antisocial Personality Disorder and Conduct Disorder: An Updated Meta-Analysis

The associations between physiological measures (i.e., heart rate and skin conductance) of autonomic nervous system (ANS) activity and severe antisocial spectrum behavior (AB) were meta-analyzed. We used an exhaustive partitioning of variables relevant to the ANS-AB association and investigated four highly relevant questions (on declining effect sizes, psychopathy subscales, moderators, and ANS measures) that are thought to be transformative for future research on AB. We investigated a broad spectrum of physiological measures (e.g., heart rate (variability), pre-ejection period) in relation to AB. The search date for the current meta-analysis was on January 1^st, 2020, includes 101 studies and 769 effect sizes. Results indicate that effect sizes are heterogeneous and bidirectional. The careful partitioning of variables sheds light on the complex associations that were obscured in previous meta-analyses. Effects are largest for the most violent offenders and for psychopathy and are dependent on the experimental tasks used, parameters calculated, and analyses run. Understanding the specificity of physiological reactions may be expedient for differentiating between (and within) types of AB.

Profiles of Emotion Regulation and Post-Traumatic Stress Severity among Female Victims of Intimate Partner Violence

Emotional dysregulation is a construct that has drawn substantial attention as a transdiagnostic contributing factor to the loss of health. Intimate partner violence (IPV) is a term used to describe physical, psychological, or sexual assault of a spouse or sexual partner. The aim of the study was to determine the variability of emotional dysregulation among women with different types of IPV revictimization and post-traumatic stress. The cross-sectional survey included 120 women attended by the Integrated Monitoring System of Gender Violence of Madrid, Spain, due to a gender violence complaint. The presence of post-traumatic stress disorder (DSM 5 criteria), emotional dysregulation (Emotional Processing Scale (EPS)), childhood trauma, and type of revictimization were evaluated. Cluster analysis found three profiles of emotional regulation: Emotionally Regulated, Avoidance/Non-Impoverished, and Emotional Overwhelm. The results showed that the Emotional Overwhelm group was characterized by a general dysregulation of emotional experiences and a greater intensity of post-traumatic stress symptoms. In addition, women who have suffered several episodes of IPV by different partners showed a differential pattern of emotional regulation than the rest of the victims that entailed greater psychopathology. Findings confirm that emotional dysregulation is a critical pathway to the decrease of health among IPV victims.

Hormonal Differences in Intimate Partner Violence Perpetrators When They Cope with Acute Stress: A Pilot Study

BACKGROUND

Only a few studies have paid attention to the ability of perpetrators of intimate partner violence (IPVAW) against women to cope with acute stress, including hormonal parameters. In fact, previous studies assessed how salivary testosterone (Tsal) and cortisol (Csal) changed after coping with an acute emotional stressor (directly related to IPVAW), and they concluded that an imbalance between the two hormones might be characteristic of these men. Nevertheless, they neglected to examine the role of other hormones, such as salivary oxytocin (OXsal), which also seemed to play an important role in behavioral regulation, and whether this response could be generalized to other types of stress not directly related to IPVAW.

METHODS

This study aims to assess whether IPVAW perpetrators (n = 19) present differential hormonal (Tsal, Csal, OXsal and their ratios) and psychological state (anxiety, anger, and general affect) responses when coping with an acute cognitive laboratory stressor (a set of neuropsychological tests performed in front of an expert committee) in comparison with non-violent men (n = 16). This quasi-experimental study also assessed whether the psychological state variables drive this different hormonal response.

RESULTS

Our results revealed that IPVAW perpetrators had lower Csal and higher Tsal/Csal ratio levels during the post-task period, as well as higher total levels (average) of OXsal than controls. We also found that, only in IPVAW perpetrators, high levels of baseline anxiety and negative affect were related to high rises in Csal during the stress task.

CONCLUSIONS

These data present a background showing that IPVAW perpetrators and non-violent men cope differently with stress. These findings might help to identify idiosyncratic profiles of IPVAW perpetrators that can then be employed to establish their therapeutic needs. Moreover, we reinforced the importance of combining biological markers with self-reports, thus increasing the reliability of these forensic assessments.

Intimate Partner Violence: A Bibliometric Review of Literature

Intimate partner violence (IPV) is a worldwide public health problem. Here, a bibliometric analysis is performed to evaluate the publications in the Intimate Partner Violence (IPV) field from 2000 to 2019 based on the Science Citation Index (SCI) Expanded and the Social Sciences Citation Index (SSCI) databases. This work presents a detailed overview of IPV from aspects of types of articles, citations, h-indices, languages, years, journals, institutions, countries, and author keywords. The results show that the USA takes the leading position in this research field, followed by Canada and the U.K. The University of North Carolina has the most publications and Harvard University has the first place in terms of h-index. The London School of Hygiene and Tropical Medicine leads the list of average citations per paper. The Journal of Interpersonal Violence, Journal of Family Violence and Violence Against Women are the top three most productive journals in this field, and Psychology is the most frequently used subject category. Keywords analysis indicates that, in recent years, most research focuses on the research fields of "child abuse", "pregnancy", "HIV", "dating violence", "gender-based violence" and "adolescents".

Alexithymia as a Predictor of Arousal and Affect Dysregulations when Batterers with Attention Deficit Hyperactivity Disorder Cope with Acute Stress

Empirical research has stated that Attention Deficit Hyperactivity Disorder (ADHD) might underlie intimate partner violence against women (IPVAW) perpetration. Even though there is a clear relationship between these two variables, it is still unknown how ADHD facilitates violence proneness. In this regard, psychophysiological variables such as skin conductance levels (SCL) might offer information about emotional regulation when individuals cope with stress. Furthermore, alexithymia traits might be a strong candidate in explaining the above-mentioned emotional dysregulations. Hence, we compared the SCL response to acute cognitive stress in IPVAW perpetrators with and without ADHD symptoms to that of controls (non-violent and unaffected), and we also assessed the presence of alexithymia traits and their role in emotional regulation. Our data point out that ADHD IPVAW perpetrators presented higher SCL and negative affect than controls, particularly during the recovery period. Moreover, ADHD IPVAW perpetrators showed higher self-reported alexithymia, and this variable was a good predictor of autonomic and psychological state dysregulations, even after controlling for the effects of alcohol and drug misuse. Therefore, our study reinforces the need to consider psychophysiological measurements when screening the therapeutic needs of IPVAW perpetrators, due to their relatively low cost and the significant contents of their results. Finally, we also highlight the key role of alexithymia in this violent population, which should be considered when designing cognitive intervention training coadjutant to current psychotherapies for IPVAW perpetrators.

Long-Term Drug Misuse Increases the Risk of Cognitive Dysfunctions in Intimate Partner Violence Perpetrators: Key Intervention Targets for Reducing Dropout and Reoffending

Intimate partner violence against women (IPVAW) is a major public health problem, with an important mortality rate in women across the world. In this regard, it has been well-established that drug misuse explains (at least in part) an increased risk of IPVAW perpetration. Even though alcohol is the most widely studied drug underlying IPVAW, other drugs, such as cannabis and cocaine also seem to be significant indicators of this type of violence. Nonetheless, little is known about mediators, such as cognitive domains that facilitate proneness to violence after drug consumption. Therefore, the primary objective of the present study was to compare drug misuse patterns and cognitive performance in a carefully selected sample of IPVAW perpetrators (n = 63) and a group of non-violent men (control group; n = 39). Second, we also aimed to study the association between different patterns of drug misuse and cognitive performance and several facets of IPVAW perpetration (i.e., severity of injuries and type of aggression). Our results revealed that IPVAW perpetrators showed considerably higher levels of sustained drug misuse (alcohol, cannabis, cocaine, and heroin) for years and worse cognitive performance than controls. Moreover, the highest drug misuse sustained over time was related to the worst cognitive performance and the highest IPVAW severity. Finally, alcohol and cocaine seemed to be related to IPVAW and risk of reoffending. Whereas, cannabis, heroin, and MDMA were related to the existence of a previous criminal record (delinquency without violence). Hence, research in this field would help to develop coadjutant treatments and intervention packages to reduce drug misuse in the initial stages, which in turn would reduce cognitive impairments in IPVAW perpetrators. These expected improvements might produce an increase in treatment adherence and a decrease in the risk of future IPVAW reoffending.

The Importance of Considering Alexithymia during Initial Stages of Intimate Partner Violence Interventions to Design Adjuvant Treatments

Empirical evidence supports that individuals with alexithymia might be prone to certain types of violence, such as intimate partner violence against women (IPVAW). Moreover, considering that alexithymia is directly involved in behavior regulation, problems due to identifying and regulating emotional states might be postulated as responsible, at least in part, for the success of psychotherapeutic treatments designed for decreasing the future risk of reoffending. Therefore, we assessed whether alexithymia was a good predictor of the discontinuation of treatment (dropout) and the risk of recidivism during the initial stages of intervention in a sample of men convicted of IPVAW perpetration (n = 118), while controlling for potential confounding variables (i.e., socio-demographic characteristics, impulsivity, and drug misuse). Our data demonstrate that high alexithymic traits lead to dropout and a high risk of recidivism during the initial stages of treatment, remaining significant even after including potential confounding variables. Even though impulsivity and drug misuse increase the amount of explained variance, none of them moderates the association of alexithymia with dropout and/or reoffending. It should be noted that this study identified alexithymia as a direct modulator of violence due to its effects on discontinuing IPVAW treatment during initial stages. Therefore, as we gain knowledge analyzing the relationships between previously mentioned factors, it could be applied to develop valid screening methods along with strengthening current rehabilitation programs and designing adjuvant treatments to increase their effectiveness.