Reduced brain activation in violent adolescents during response inhibition

Acute Exercise Improves Inhibitory Control but Not Error Detection in Male Violent Perpetrators: An ERPs Study With the Emotional Stop Signal Task

Violence has been linked to the co-occurrence of cognitive dysfunction and altered activations in several brain regions. Empirical evidence demonstrated the benefits of acute exercise on motor inhibition and error detection and their neuronal processing. However, whether such effects also hold for the population with violent behaviors remains unknown. This study examined the effects of acute aerobic exercise on inhibitory control and error monitoring among violent offenders. Fifteen male violent offenders were counterbalanced into experimental protocols, which comprised a 30-min moderately aerobic exercise [60% heart rate (HR) reserve] and a 30-min reading control session. After each session, participants performed an emotional stop signal task while event-related potentials (ERPs) were recorded simultaneously. Results showed insignificant changes in ERPs components [i.e., N2, P3, error-related negativity (ERN), and error-positivity (Pe) amplitudes] and the behavioral performance in go condition, stop accuracy, and post-error adjustments by exercise. However, the current study demonstrated that the acute exercise facilitated stop signal reaction time (SSRT) when compared to the control session regardless of emotional conditions. This is the first research to exhibit the improvements in inhibitory performance by acute exercise for violent offenders. Most importantly, this effect was independent of affective settings, expanding the existing knowledge of the influences of acute exercise on cognition. Our findings implicate the perspective of acute exercise for clinical and correctional practices.

Depression, Rumination, and Impulsive Action: A Latent Variable Approach to Behavioral Impulsivity

Previous research on the relationship between rumination and behavioral impulsivity has been limited because impulsivity was assessed by using individual tasks. This study examined the concurrent associations of a latent variable named impulsive action with rumination and depression to alleviate the task-impurity problem and the low reliability of laboratory tasks assessing impulsivity. This study also examined whether stressors mediated the association between impulsive action and rumination. University students in Japan (N = 176) conducted three laboratory tasks assessing impulsive action: the Go/No-Go Task, the Stop Signal Task, and the Conners Continuous Performance Test 3rd Edition. They also completed self-report measures of rumination, stressors, and depression. Results indicated that the latent variable named impulsive action constructed from the performance in these three tasks was positively associated with rumination. Moreover, stressors mediated this association. Also, impulsive action was positively associated with depression via the increase in stressors and rumination. These findings and those of previous studies examining associations between rumination and self-reported impulsivity suggest that impulsivity might be a determinant of rumination.

Response inhibition deficits are positively associated with trait rumination, but attentional inhibition deficits are not: aggressive behaviors and interpersonal stressors as mediators

Previous findings on relationships between inhibition that is a core executive function, and trait rumination have been inconsistent. This inconsistency could be overcome by investigating the association between rumination and the two subcomponents of inhibition: response inhibition and attentional inhibition. This study examined whether and how response inhibition and attentional inhibition were related to rumination as well as worry. University students in Japan (N = 213) conducted the Go/No-Go Task and the Modified Stroop Task. They also completed self-report measures of depression, trait rumination, trait worry, stressors, and aggressive behaviors. Results indicated that response inhibition deficits were positively associated with trait rumination, and this association was mediated by increases in aggressive behaviors and interpersonal stressors. The associations between these variables remained significant even after controlling for depression level. There were no significant direct or indirect associations between attentional inhibition deficits and rumination. These results suggest that response inhibition deficits, among the subcomponents of inhibition, have an indirect positive association with rumination through interpersonal processes. Results also showed nonsignificant differences between rumination and worry in the magnitude of correlation coefficients with the two subcomponents of inhibition. Therefore, it remains unclear whether the positive association with response inhibition is unique to rumination.

Resting-state functional magnetic resonance imaging investigation of the neural correlates of cognitive-behavioral therapy for externalizing behavior problems in adolescent bullies

The purpose of this study was to investigate the neural correlates of cognitive-behavioral therapy (CBT) for externalizing behavior problems in perpetrators of school bullying using assessments of brain activity and behavior. Twenty-five adolescent bullies participated in an 8-session intervention. Prior to and after participation, 24 adolescents were evaluated using the Child Behavior Checklist (CBCL) and 23 completed resting-state functional magnetic resonance imaging. Changes in the fractional amplitude of low-frequency fluctuations (fALFF) and scores on the CBCL were analyzed. We also compared the identified changes into 2 groups (low and high delinquency) differentiated by a cutoff of 65 points on the delinquency subscale of the CBCL. Following the intervention, participants exhibited improvement in the subscores of the CBCL and decreases in the fALFF of the inferior parietal lobule, lingual, interior frontal and middle occipital gyrus. A positive correlation was observed between changes in the CBCL externalizing behavior scores and fALFF of the inferior frontal gyrus. The high delinquency group showed a greater decrease in delinquency and externalizing CBCL subscores across time than did the low delinquency group. The high delinquency group had more areas that showed change in fALFF post-intervention than did the low delinquency group. A positive correlation was observed between changes in the CBCL delinquency scores and fALFF of the precentral gyrus in the high delinquency group. The results indicate that this CBT for externalizing behavior problems in bullies had more positive effects on delinquent behavior in adolescents with high levels of delinquency, and these changes were associated with functional changes in brain activity.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02670876.

The Role of the Hippocampus in Predicting Future Posttraumatic Stress Disorder Symptoms in Recently Traumatized Civilians

BACKGROUND

Understanding the neurobiological mechanisms that predict posttraumatic stress disorder (PTSD) in recent trauma survivors is important for early interventions. Impaired inhibition of fear or behavioral responses is thought to be central to PTSD symptomatology, but its role in predicting PTSD is unknown. Here we examine whether brain function during response inhibition early after a civilian trauma can predict future PTSD symptoms.

METHODS

Participants (original sample, n = 27; replication sample, n = 31) were recruited in the emergency department within 24 hours of trauma exposure. PTSD symptoms were assessed in the emergency department and 1, 3, and 6 months posttrauma. A Go/NoGo procedure in a 3T magnetic resonance imaging scanner was used to measure neural correlates of response inhibition 1 to 2 months posttrauma. Elastic net regression was used to define the most optimal model to predict PTSD symptoms at 3 and 6 months among demographic, clinical, and imaging measures.

RESULTS

Less hippocampal activation was a significant predictor in the model predicting PTSD symptoms at 3 months (F_11,22 = 4.33, p = .01) and 6 months (F_9,19 = 4.96, p = .01). Other significant predictors in the model were race and pain level in the emergency department (3 months), and race and baseline depression symptoms (6 months). Using these predictors in a linear regression in the replication sample again resulted in significant models (3 months [F_3,23 = 3.03, p = .05], 6 months [F_3,20 = 5.74, p = .007]) with hippocampal activation predicting PTSD symptoms at 3 and 6 months.

CONCLUSIONS

Decreased inhibition-related hippocampal activation soon after trauma predicted future PTSD symptom severity. This finding may contribute to early identification of at-risk individuals and reveals potential targets for intervention or symptom prevention in the aftermath of trauma.

Parental Education and Aggressive Behavior in Children: A Moderated-Mediation Model for Inhibitory Control and Gender

Aggressive behaviors are highly prevalent in children. Given their negative consequences, it is necessary to look for protective factors that prevent or reduce their progress in early development before they become highly unshakable. With a sample of 147 children, the present study aimed to assess the relation between parental education and inhibitory control in the aggressive behavior of children aged from 7 to 10 years. The participants completed a go/no-go task to assess inhibitory control, whilst their parents reported their education level, and their teachers rated the aggressive behavior of the children through the Teacher Rating Scale (TRS) of the Behavior Assessment System for Children 2 (BASC-2). The results showed that both parental education and inhibitory control determined aggressive behavior in children. In addition, inhibitory control partially mediated the associations between parental education and aggressive behavior after accounting for age. However, a moderated mediation model revealed that lower parental education was associated with higher levels of aggressive behavior, which, in girls occurred independently of inhibitory control. In contrast, inhibitory control mediated this relation in boys. These results suggest the importance of parental education and inhibitory control in the aggressive behavior of children, supporting the idea that both constructs are relevant for understanding these conduct problems in schools, particularly in boys. The clinical implications of these findings are discussed, along with possible future lines of investigation.