Impulsivity and Adolescent Substance Use: From Self-Report Measures to Neuroimaging and Beyond

Abstract

The capacity to regulate emotional impulses and pursue appropriate long-term goals is an integral part of adaptive human functioning. Therefore, it is not surprising that this capacity consistently emerges as a core trait in biologically-based models of personality. Variously labeled as “impulsivity,” “sensation seeking,” or “constraint” amongst other terms, variations in this trait reliably predict the development of substance use problems in prospective studies. Notably, marked increases in this impulsivity trait appear during adolescence – a period of life when substance experimentation and abuse typically begins. In recent years, neuroimaging research has identified the orbitofrontal and anterior cingulate cortices as important neural substrates of trait impulsivity. Interestingly, these same brain regions undergo substantial development during the teenage years. Indeed, there is remarkable consistency in the time course of these neural changes with those at the level of personality, suggesting both the imaging scanner and the self-report questionnaire are tapping into the same underlying construct, albeit with a differing degree of precision. Despite its far greater precision, the scanner itself cannot be practically employed in large-scale prevention programs to identify teens at risk. However, in validating the biological basis of impulsivity, along with behavioral and self-report measures of the trait, neuroimaging research allows one to use these more cost-effective tools in primary prevention with greater confidence. Indeed, there is already evidence demonstrating the ability of such “blunt” tools to focus and improve prevention programs.