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

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