Brain responses may signal near-term substance-use risk in girls

A blunted P300, an event-related potential indicator of attentional processes, and blunted late positive potential (LPP), an event-related potential indicator of elaborative processing, confer risk for development of substance use disorders (SUD) in adolescents. However, few studies have examined whether electrophysiological reactivity to emotional stimuli predicts development of SUD in adolescents. It is also unclear whether these neural responses are a risk factor of proximal, precocious development of SUD versus distal SUD later in adolescence. The present study examined whether electrophysiological reactivity to emotional images and targets prospectively associated with the development of cannabis, alcohol, and illicit drug use disorders in adolescent girls. The sample included 491 13.5-15.5-year-old girls with no baseline history of a SUD or depressive disorders. Participants completed the emotional interrupt task, and we recorded electroencephalography to measure the LPP to emotional image distractors and the P300 to targets. Participants also completed the Kiddie Schedule for Affective Disorders and Schizophrenia diagnostic interview to assess the onset of SUD 18 and 36 months later. A blunted LPP to emotional image distractors and a blunted P300 to targets independently associated with increased likelihood of onset of SUD at 18 months (but not 36 months). The LPP and P300 were not correlated, potentially suggesting dissociable pathways. The present study suggests electrophysiological reactivity to emotional images and targets prospectively index risk for the development of SUD in adolescent girls. In addition, these neural measures associate with more proximal, but not distal, onsets of SUD.