Executive functions and predicting the onset of drinking and heavy drinking in young adolescents
Background: Executive functioning (EF) has repeatedly been associated with the use and misuse of alcohol and other substances in adolescence. Impairments in executive functions, such as response inhibition and working memory, important for organizing, controlling and planning of behavior have been found to be predictive of problematic and heavy alcohol use in adolescents. How these functions are related to the initiation of alcohol use (and other substances) has less often been studied in early adolescence. Method: Results of two different studies are presented. The first sample included 534 adolescents (69% boys) between 12 and 15 years at baseline. Two measures of EF, response inhibitions and working memory, were assessed at four different waves including a period of two years, and outcomes were linked to the onset of drinking and the onset of binge drinking. In a second study (TRAILS study), 715 adolescents (49% boys) were followed over a period of 5 years (11-16) years. Participants completedmeasures of EF (response inhibition and working memory), effortful control and reward sensitivity. Only substance naive (alcohol and/or cannabis) adolescents were included at baseline to look at the predictive effects of behavioral control (EF + effortful control). Results: The results of the survival analysis in the first study demonstrated that the onset of alcohol use and the onset of binge drinking was predicted by weak EF functioning. That is, adolescents with relatively poor EF, initiated alcohol use and binge drinking at a younger age compared to adolescents with relatively good EF. In the second study, only effortful at age 11 predicted alcohol and cannabis use at age 16, and only for those who weremore reward sensitive. We did not find an effect of EF on cannabis or alcohol use. Discussion: The findings of both studies highlight the important role of EF and behavioral control, in relation to the onset of drinking and cannabis use in young adolescents. These results are important in relation to previous results linking cognitive deficits to alcohol use. It appears that some deficits are present before alcohol or cannabis use is initiated.