FIGURE 1. Major Motivational Brain Circuitry Putatively Involved in Impulsivity, Decision Making, and Drug Addiction^a.

^a Primary motivation circuitry directly subserves the neurocomputational events of decision making and the selection of motivational drives for behavioral action. These events are determined by subsystems integral to cortical-striatal-thalamic-cortical pathways (open yellow arrow) that can either promote or inhibit the enactment of motivated drives. Secondary motivation circuitry provides the input (affective, memory, sensory, hormonal/homeostatic information) that generates and influences the fate of motivational drives in primary motivation circuitry. Addictive drugs, primarily by virtue of neuroplastic changes associated with dopamine activity most highly concentrated in primary motivation circuitry, produce long-term motivational effects.