Onset of substance use: Deviant peer, sex, and sympathetic nervous system predictors

Dampened autonomic nervous system responses to stress and substance use in adolescence

We investigated whether parasympathetic and sympathetic nervous system (SNS) responses to social-evaluative threat at age 14 were related to the number of substances used between ages 14 and 16 among Mexican-origin adolescents (N = 243; 70.4% had never used substances by 14). Participants completed the Trier Social Stress Test, while cardiac measures of parasympathetic and SNS activity were measured continuously using respiratory sinus arrhythmia (RSA) and pre-ejection period (PEP), respectively. Participants reported whether they had ever used alcohol, marijuana, and cigarettes, and had ever vaped nicotine in their lifetime at ages 14 and 16. Multilevel models were used to test associations between RSA and PEP responses at age 14 and substance use at 16. Among youth who had not used substances by 14, dampened RSA and PEP responses, and profiles of greater coinhibition and lower reciprocal SNS activation between RSA and PEP, at age 14 were associated with using substances by 16. Among youth who used by 14, exaggerated PEP responses were associated with using more substances by age 16. Taken together, dampened autonomic responses to social-evaluative threat predicted initiation of substance use over two years, and difficulties with coordination of physiological responses may confer risk for substance use in adolescence.

Deviant Peer Affiliation and Adolescent Tobacco and Alcohol Use: The Roles of Tobacco and Alcohol Information Exposure on Social Networking Sites and Digital Literacy

Due to the prevalence and severe harm of adolescent tobacco and alcohol use, researchers have been paying attention to its influencing factors. From the perspective of the ecological techno-subsystem theory, this study aimed to examine the correlations between deviant peer affiliation, tobacco and alcohol information exposure on social networking sites (SNSs), and adolescent tobacco and alcohol use, as well as the potential protective role of digital literacy. In total, 725 adolescents were recruited to participate in this study. The results showed that deviant peer affiliation was positively associated with adolescent tobacco and alcohol use, SNS tobacco and alcohol information exposure mediated this association, and digital literacy moderated the relationship between SNS information exposure and tobacco and alcohol use. Specifically, the association between SNS tobacco and alcohol information exposure and adolescent tobacco and alcohol use was weaker for those with high digital literacy. These findings not only explore the combined effects of offline and online risk factors but also provide guides for preventing adolescents' tobacco and alcohol use by cultivating and enhancing digital literacy.