Methamphetamine use causes cognitive impairment and altered decision-making

Methamphetamine is a widely abused psychostimulant. It reverses transport through the dopamine transporter, thereby increasing the extracellular level of dopamine in the brain, which is associated with the rewarding effect. Repeated intake of methamphetamine leads to drug addiction, a chronically relapsing disorder characterized by compulsive drug taking, inability to limit intake, and intense drug cravings. The molecular and cellular mechanisms of drug addiction are not well understood, but have been proposed to involve neural plasticity and the remodeling of specific brain circuits. Accumulating evidence also indicates that patients addicted to methamphetamine exhibit impaired cognitive functions such as executive function, attention, social cognition, flexibility, and working memory. Furthermore, decision-making is altered in patients with drug addiction, including methamphetamine abusers. Cognitive impairment as well as altered decision-making in methamphetamine abusers may contribute to the high rate of relapse even after long-term withdrawal with psychosocial support. In this article, we review the effect of methamphetamine on cognition and decision-making in rodents. We also discuss possible mechanisms underlying cognition and decision-making impairments, including neuronal circuits, molecular and cellular events, and action control, as well as potential therapeutic targets.