The PFC is a key brain region regulating executive cognitive function, attention, and working memory. Dysregulation of normal signaling in the PFC, paralleled by deficits in cognitive performance, have been observed in disorders such as Alzheimer's disease, schizophrenia, ADHD, and Parkinson's disease (Picciotto and Zoli, 2002). Interestingly, nicotine has been shown to enhance cognition and attention in people suffering from these disorders (Rezvani and Levin, 2001). The PFC has extensive connections to reward and memory hubs, receiving DA innervations from the VTA and providing glutamatergic efferents to the VTA and NAc (Sesack et al., 1989; Carr and Sesack, 2000). It is now well established that drugs of abuse may take over the normal operations of this system, driving impulsivity and compulsive behaviors characteristic of addiction (Lasseter et al., 2010). Recent neuroimaging studies of PFC activity in drug-addicted subjects point to global dysfunction in this region that is associated with a greater incidence of relapse and heavier drug use (Goldstein and Volkow, 2011).
