Effect of alcohol use on the adolescent brain and behavior

Abstract

Adolescence is a particularly vulnerable neurodevelopmental period marked by high rates of engagement with risky alcohol use. This review summarizes the cognitive and neural consequences following alcohol use during adolescence from longitudinal design studies in humans and animals. Findings from human adolescent studies suggest that binge drinking and heavy alcohol use is associated with poorer cognitive functioning on a broad range of neuropsychological assessments, including learning, memory, visuospatial functioning, psychomotor speed, attention, executive functioning, and impulsivity. Alcohol use during adolescence is associated with accelerated decreases in gray matter and attenuated increases in white matter volume, and aberrant neural activity during executive functioning, attentional control, and reward sensitivity tasks, when compared to non-drinking adolescents. Animal studies in rodents and non-human primates have replicated human findings, and suggest cognitive and neural consequences of adolescent alcohol use may persist into adulthood. Novel rodent studies demonstrate that adolescent alcohol use may increase reward responsiveness of the dopamine system to alcohol later in life, as well as disrupt adolescent neurogenesis, potentially through neuroinflammation, with long-lasting neural and behavioral effects into adulthood. Larger longitudinal human cognitive and neuroimaging studies with more diverse samples are currently underway which will improve understanding of the impact of polysubstance use, as well as the interactive effects of substance use, physical and mental health, and demographic factors on cognition and neurodevelopment.

Figure 1:

Prevalence of current alcohol use and binge drinking in adolescents aged 15 to 19. In this data, binge drinking was defined as 60+ grams of pure alcohol (~4 standard US drinks) on at least one occasion per month (33).

Figure 2:

Alcohol use classification chart. ¹ Binge drinking is typically ≥4 drinks within 2 hours (females) and ≥5 drinks within 2 hours (males), where the blood alcohol concentration (BAC) level rises to 0.08 g/dL (39). The chart is based on the National Institute on Alcohol Abuse and Alcoholism, and Substance Abuse and Mental Health Services Administration levels of alcohol use definitions (39, 40).