Article

Decision making, impulse control and loss of willpower to resist drugs: a neurocognitive perspective

Institute for the Neurological Study of Emotion and Creativity, Department of Psychology, University of Southern California, Los Angeles, California 90089-2520, USA.
Nature Neuroscience (Impact Factor: 14.98). 12/2005; 8(11):1458-63. DOI: 10.1038/nn1584
Source: PubMed

ABSTRACT Here I argue that addicted people become unable to make drug-use choices on the basis of long-term outcome, and I propose a neural framework that explains this myopia for future consequences. I suggest that addiction is the product of an imbalance between two separate, but interacting, neural systems that control decision making: an impulsive, amygdala system for signaling pain or pleasure of immediate prospects, and a reflective, prefrontal cortex system for signaling pain or pleasure of future prospects. After an individual learns social rules, the reflective system controls the impulsive system via several mechanisms. However, this control is not absolute; hyperactivity within the impulsive system can override the reflective system. I propose that drugs can trigger bottom-up, involuntary signals originating from the amygdala that modulate, bias or even hijack the goal-driven cognitive resources that are needed for the normal operation of the reflective system and for exercising the willpower to resist drugs.

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