Social isolation is closely linked to a marked reduction in physical activity in male mice.

The effects of social isolation on an individual's behavior is an important field of research, especially as public health officials encourage social distancing to prevent the spread of pandemic disease. In this study we evaluate the effects of social isolation on physical activity in mice. Utilizing a pixel-based tracking system, we continuously monitored the movement of isolated mice compared with paired cage mates in the home cage environment. We demonstrate that mice that are socially isolated dramatically decrease their movement when separated from their cage mate, and especially in the dark cycle, when mice are normally most active. When isolated mice are re-paired with their original cage mate, this effect is reversed, and mice return to their prior levels of activity. These findings suggest a close link between social isolation and physical activity, and are of particular interest in the wake of coronavirus disease 2019, when many are forced into isolation. Social isolation may affect an individual's overall activity levels in humans too, which may have unintended effects on health that deserve further consideration.

The role of psychopathology in the relationship between history of maltreatment and suicide attempts among children and adolescent inpatients.

BACKGROUND: This retrospective chart review study investigates the relationship between the history of various forms of abuse and the presence of mood disorders and psychotic symptoms in predicting suicide attempts among psychiatrically hospitalized children and adolescents. METHOD: A multi-mediation analysis was conducted with an archival dataset of 101 children and adolescents hospitalized predominantly for mood disorders and bipolar disorders with and without history of psychotic symptoms. RESULTS: Results showed that history of suicide attempts was directly associated with physical abuse and indirectly associated with sexual abuse (mediated by bipolar disorders). Emotional abuse was also indirectly related to history of suicide attempts, mediated by mood disorders for boys, and by psychotic symptoms for girls. CONCLUSIONS: This study is among the first to differentiate the unique effects of different types of early maltreatment on psychopathology, particularly mood disorders and psychotic symptoms, and histories of suicide attempts in psychiatrically hospitalized children and youth. KEY PRACTITIONER MESSAGE: Little is known about the relationships between histories of maltreatment, psychopathology, and suicide (considered simultaneously) among hospitalized children and adolescents. Different forms of abuse are associated with distinct psychopathology symptoms, and in turn, risk for suicide attempts. Only physical abuse is directly related to a history of suicide attempts, while sexual and emotional abuse are indirectly related (mediated by mood disorders and psychotic symptoms). These risk pathways are partly distinct for girls and boys. Identifying unique and cumulated risk factors can help prevent suicidality among hospitalized youth.

Impact of psychotic symptoms on cognitive functioning in child and adolescent psychiatric inpatients with severe mood disorders.

Despite established differences in cognitive functioning of adults with mood disorder-related psychosis and those with non-affective psychotic disorders, there is limited evidence of the impact of psychotic symptoms on the cognitive functioning of children and adolescents with mood disorders. This study investigates IQ, working memory, and processing speed scores in 80 child and adolescent inpatients discharged from an intermediate care state psychiatric hospital, using a retrospective chart review. Associations between diagnosis based on DSM-IV criteria (7 with Major Depression- MDD; 43 with Bipolar Disorders-BD, and 30 with Mood Disorders Not Otherwise Specified-NOS), presence of current psychotic features, and cognitive functioning (WISC-IV IQ, Coding, Symbol Search, and Digit Span) were investigated using Multivariate Analyses of Variance. No differences were found in cognitive functioning between patients with MDD and BD, or between those with severe Mood Disorders (MDD or BD) and those with NOS, when controlling for age, gender, and presence of psychotic features. However, patients with severe mood disorders and psychotic features showed lower IQs and greater working memory deficits than those without psychotic features or NOS. Results are discussed in terms of treatment planning for children and adolescents at risk for developing psychotic symptoms and severe mood disorders.

Social Involvement Modulates the Response to Novel and Adverse Life Events in Mice.

Epidemiological findings suggest that social involvement plays a major role in establishing resilience to adversity, however, the neurobiology by which social involvement confers protection is not well understood. Hypothesizing that social involvement confers resilience by changing the way adverse life events are encoded, we designed a series of behavioral tests in mice that utilize the presence or absence of conspecific cage mates in measuring response to novel and adverse events. We found that the presence of cage mates increased movement after exposure to a novel environment, increased time spent in the open arms of the elevated plus maze, and decreased freezing time after a foot shock as well as expedited fear extinction, therefore significantly changing the response to adversity. This is a first description of a mouse model for the effects of social involvement on adverse life events. Understanding how social involvement provides resilience to adversity may contribute to the future treatment and prevention of mental and physical illness.