Loss of willpower: Abnormal neural mechanisms of impulse control and decision making in addiction

Addiction is a condition in which the person becomes unable to choose according to long-term outcomes when it comes to drugs. We will argue that this is the product of an imbalance between two separate, but interacting, neural systems: (1) an impulsive, amygdala-dependent system for signaling the pain or pleasure of immediate prospects and (2) a reflective, orbitofrontal-dependent system for signaling the prospects of the future. The conditions that lead to this imbalance include (1) a dysfunctional reflective system and (2) a hyperactive impulsive system. In other words, drugs can acquire properties of triggering bottom-up, involuntary signals through the amygdala that modulate, bias, or even "hijack," top-down, goal-driven attentional resources needed for the normal operation of the reflective system and exercising the will. © 2006 by Sage Publications, Inc.SCOPUS: ch.b