Unraveling the Role of the Amygdala in Nicotine Addiction

Abstract

Through the use of tobacco, nicotine is one of the most heavily used addictive drugs. Current neurobiological perspectives suggest that chronic nicotine exposure is associated with alterations in emotional and motivational brain circuits. Together with the reinforcing effects of nicotine, these neural adaptations are thought to be critical for the development and maintenance of an addicted state despite its potentially harmful consequences. Although the amygdala is crucially involved in detecting environmental threat signals, less is known about its role in nicotine addiction. We here review neuroimaging findings showing that the amygdala may substantially contribute to the development and maintenance of nicotine addiction via three different mechanisms. First, the amygdala shows strong reactivity to smoking-related stimuli, thereby eliciting cue-induced craving. Second, the amygdala is crucially involved in evoking negative emotional states during early abstinence. Third, there is mounting evidence for deficient amygdala-dependent threat and risk perception, perhaps promoting disinhibited nicotine seeking.