Linking Sleep and Aggression: The Role of Response Inhibition and Emotional Processing

Although shorter sleep duration is theorized to increase the risk of engaging in aggressive behavior, experimental studies examining this relationship yield conflicting findings. Since sleep serves in part to regulate the functioning of prefrontal brain regions, insufficient sleep may deleteriously impact the individual’s ability to inhibit rash action and alter emotional processing, which could in turn increase aggressive tendencies. However, no studies have examined the extent to which naturally occurring insufficient sleep is linked to aggression or potential mechanisms of this relationship, limiting understanding of and the generalizability of extant findings. Thus, the present study examined whether cognitive (deficits in response inhibition) and emotional processes (increased negative emotional processing) help explain relationships between sleep duration and aggression. Approximately 143 participants between the ages of 18 and 40 were recruited from a larger, grant-funded aggression study. Participants wore Fitbit Flex sleep-tracking devices and kept a sleep diary to monitor sleep duration over a three-day period prior to the laboratory session. At the laboratory session, electrophysiological indices of emotional processing and response inhibition (P3 and N2) were measured via an Emotional Go/No-Go task, and aggression under provocation was measured using a laboratory aggression paradigm. Mixed-model repeated measure ANOVAs tested the relationships between sleep duration, emotional processing, response inhibition, and aggression, controlling for potential confounds (e.g., substance abuse, gender). Path analyses examined whether emotional processing and response inhibition mediated the sleep-aggression relationship. As expected, less sleep duration was associated with greater intensity of aggression observed in the laboratory. Interestingly, despite showing increased inhibition processing towards emotional stimuli, lower sleepers performed similarly across emotional conditions, indicating that the emotional processing biases apparent at lower levels of sleep did not translate to better performance. Moreover, although inhibitory and emotional processing related to sleep and aggression, albeit in somewhat different patterns, these mechanisms did not explain the sleep-aggression link. These results provide the first evidence that shorter sleep duration predicts laboratory aggressive behavior, and preliminarily suggests that shorter sleepers work harder in emotional contexts to inhibit behavior comparably to neutral contexts. Implications of these findings for understanding aggression will be discussed

Linking Insomnia and Suicide Ideation: The Role of Socio-Cognitive Mechanisms in Suicide Risk

Despite what is known about predictors of suicide risk and consequences of insomnia, research has yet to delineate mechanisms that may explain the known relationship between insomnia symptoms and suicide risk. There is some disagreement in the literature regarding whether this relationship could be primarily explained by recent depressive symptoms, or whether there may be other explanatory factors related to sleep deficits. The present study addressed this contention in the literature by examining 1) whether socio-cognitive variables (e.g. fatigue, appraised social problem-solving ability, and hopelessness) explained this insomnia-ideation relationship, and 2) whether these variables contributed some explanatory variance in suicide ideation above and beyond that explained by depressive symptoms. Approximately 483 female participants completed an online study survey. Cross-sectional path analyses were conducted in order to examine the initial hypothesized path, as well as whether the path persisted when depression was integrated in the model. Results suggest that the hypothesized socio-cognitive factors related to sleep deficits partially mediate the established insomnia-suicide ideation relationship. And, further, that the socio-cognitive pathway from sleep loss to suicide ideation persists even when accounting for recent depressive symptoms, such that both pathways separately explain some degree of this relationship. These findings have meaningful implications for understanding mechanisms by which insomnia symptoms may confer heightened risk for considering suicide

Threat Effects on Cognitive Systems: Testing Links to Aggression Proneness

The biobehavioral study of aggression has implications for expanding our understanding of transdiagnostic processes that increase risk for disinhibited behaviors. Towards this end, our study tested tenets from the process model of aggression (Verona & Bresin, 2015) that the predictability of threat would differentially alter cognitive networks, including attentional alerting and executive control. Further, we examined whether threat-related changes in cognitive functioning are associated with self- and informant-reports of aggressive actions. Using event-related potential (ERP) measures of cognitive-attentional processes, 143 community individuals participated in a well-validated and translational threat manipulation (NPU task; Schmitz & Grillon, 2012) while completing the Attention Network Test (Posner et al., 1980). Analyses revealed that unpredictable threat quickened alerting-related reaction time, whereas predictable threat interfered with processing of flanker task stimuli. The results, however, failed to show reliable relationships between aggression proneness and threat-related cognitive alterations. The findings fit with a broader literature on cognitive and behavioral outputs of threat activation and provide fruitful avenues for better understanding threat-related aggression

Aggressiveness, inhibitory control, and emotional states: A provocation paradigm

The current study examines the effects of trait aggressiveness, inhibitory control and emotional states on aggressive behaviour in a laboratory paradigm. One hundred fifty-one adult participants took part (73 men, 71 women, and seven non-disclosed). Event Related Potentials (ERPs) during a Go/No-Go task were utilised to capture the extent of inhibitory processing, with a laboratory provocation paradigm used to assess aggression. Contrary to the expectations, negative affective responses to provocation were negatively associated only with short-lived aggression and only among those with high past aggressiveness. Furthermore, past aggressiveness was related to a continuous increase in laboratory aggressive behaviour regardless of the level of inhibitory control (P3 difference amplitude). However, feeling hostile was associated with short-lived aggressive behaviour, only in those with lower levels of inhibitory control. These findings demonstrate the effect of distinct mechanisms on different patterns of aggressive behaviour

A Silenced Population: Uncovering Correlates Of Suicidal-Related Behavior Among Deaf And Hard-Of-Hearing Youth

Background: Given challenges that exceed the normal developmental requirements of adolescence, deaf and hard-of-hearing (DHH) youth are believed to be at elevated risk for engaging in suicide-related behavior (SRB). Unfortunately, little is known about the mechanisms that put these youth potentially at risk. Aims: To determine whether peer relationship difficulties are related to increased risk of SRB in DHH youth. Method: Student records (n = 74) were retrieved from an accredited educational center for deaf and blind students in the United States. Results: Peer relationship difficulties were found to be significantly associated with engagement in SRB but not when accounting for depressive symptomatology. Limitations: The restricted sample limits generalizability. Conclusions regarding risk causation cannot be made due to the cross-sectional nature of the study. Conclusion: These results suggest the need for future research that examines the mechanisms of the relationship between peer relationship difficulties, depression, and suicide risk in DHH youth and potential preventive interventions to ameliorate the risks for these at-risk youth

Adolescent Depression: Differential Symptom Presentations In Deaf And Hard-Of-Hearing Youth Using The Patient Health Questionnaire-9

The present study examined differences in symptom presentation in screening for pediatric depression via evaluation of the Patient Health Questionnaire-9 (PHQ-9). In particular, we examined whether PHQ-9 items function differentially among deaf and hard-of-hearing (DHH; n = 75) and hearing (n = 75) youth based on participants recruited from crisis assessment services. Multiple indicators multiple causes models were used to examine whether items of the PHQ-9 functioned differently between groups as well as whether there were group differences in the mean severity of depressive symptoms. Results indicate that DHH youth were more likely to endorse psychosomatic items, and less likely to endorse an affective item. These findings indicate that the PHQ-9 functions differently when used with DHH youth. Implications of these findings are discussed, including both for future work with the PHQ-9 and with regard to the conceptualization of depression across hearing groups

Suicidal thoughts and behaviours among military veterans: protocol for a prospective, observational, neuroimaging study

Introduction This study’s overarching goal is to examine the relationship between brain circuits and suicidal thoughts and behaviours (STBs) in a transdiagnostic sample of US military veterans. Because STBs have been linked with maladaptive decision-making and disorders linked to impulsivity, this investigation focuses on valence and inhibitory control circuits.Methods and analysis In this prospective, observational study, we will collect functional MRI (fMRI), cognitive and clinical data from 136 veterans (target sample size) recruited from the Providence VA Health System (PVAHS): 68 with STBs and 68 matched controls. Behavioural data will be collected using standardised measures of STBs, psychiatric symptoms, cognition, functioning and medical history. Neuroimaging data will include structural, task and resting fMRI. We will conduct follow-up interviews and assessments at 6, 12 and 24 months post-enrolment. Primary analyses will compare data from veterans with and without STBs and will also evaluate whether activation and connectivity within circuits of valence and inhibition covary with historical and prospective patterns of suicidal ideation and behaviour.Ethics and dissemination The PVAHS Institutional Review Board approved this study (2018–051). Written informed consent will be obtained from all participants. Findings from this study will be published in peer-reviewed journals and presented at local, regional, national and international conferences.Nauder Namaky, Ph.D.* [email protected]

Threat Effects on Attention Networks in Individuals with a History of Externalizing Behaviors

Research identifying the biobehavioral processes that link threat exposure to cognitive alterations can inform treatments designed to reduce perpetration of stress-induced aggression. The present study attempted to specify the effects of relatively predictable (acute) vs unpredictable (diffuse) threat on two theoretically relevant attention networks, attentional alerting and executive control; and to examine the extent to which aggression proneness moderated those effects. In a sample with high rates of externalizing behaviors (n = 74), we measured event-related brain activity during an attention network test that manipulated cognitive systems activation under distinct contexts of threat (NPU manipulation). The first set of results confirmed that threat exposure alters alerting and executive control. The predictable threat condition, relative to unpredictable threat, increased visual alerting (alert cue N1) and decreased attention (P3) to subsequent task-relevant stimuli (flanker). In contrast, overall threat and unpredictable threat conditions were associated with alerting-related quicker responding and poorer conflict resolution (congruence-related flanker N2 reductions and RT interference). The second set of results indicated that different operationalizations of aggression proneness were inconsistently related to threat-related alterations in cognitive systems. While these results regarding threat-related cognitive alterations in aggression require more study, they nevertheless expand what is known about threat-related modulation of cognition in a sample of individuals with histories of externalizing behaviors