The tension between subcortical regions relative to prefrontal cortical regions during this period may serve as a possible mechanism for the observed heightened risk-taking, including use and abuse of alcohol and drugs. The majority of adolescents have tried alcohol 93, but this does not necessarily lead to abuse. Individuals with less top-down regulation may be particularly susceptible to alcohol and substance abuse as suggested by studies of high-risk populations showing impairments in frontal functioning prior to alcohol and drug exposure (e.g. 116, 117). In the context of our neurobiological model of adolescence, these individuals would have an even greater imbalance in cortico-subcortical control. These findings are also in accordance with clinical findings in ADHD populations who show reduced prefrontal activity and are four times as likely to develop a substance use disorder compared to healthy controls 124. This imbalance in cortico-subcortical control would be further compounded by the insensitivity of adolescence to the motor and sedative effects of alcohol that otherwise may help to limit intake, and the positive influences of alcohol in social facilitation which may further encourage alcohol
