Prefrontal cortex and drug abuse vulnerability: translation to prevention and treatment interventions

Abstract

Vulnerability to drug abuse is related to both reward seeking and impulsivity, two constructs thought to have a biological basis in the prefrontal cortex (PFC). This review addresses similarities and differences in neuroanatomy, neurochemistry and behavior associated with PFC function in rodents and humans. Emphasis is placed on monoamine and amino acid neurotransmitter systems located in anatomically distinct subregions: medial prefrontal cortex (mPFC); lateral prefrontal cortex (lPFC); anterior cingulate cortex (ACC); and orbitofrontal cortex (OFC). While there are complex interconnections and overlapping functions among these regions, each is thought to be involved in various functions related to health-related risk behaviors and drug abuse vulnerability. Among the various functions implicated, evidence suggests that mPFC is involved in reward processing, attention and drug reinstatement; lPFC is involved in decision-making, behavioral inhibition and attentional gating; ACC is involved in attention, emotional processing and self-monitoring; and OFC is involved in behavioral inhibition, signaling of expected outcomes and reward/punishment sensitivity. Individual differences (e.g., age and sex) influence functioning of these regions, which, in turn, impacts drug abuse vulnerability. Implications for the development of drug abuse prevention and treatment strategies aimed at engaging PFC inhibitory processes that may reduce risk-related behaviors are discussed, including the design of effective public service announcements, cognitive exercises, physical activity, direct current stimulation, feedback control training and pharmacotherapies. A major challenge in drug abuse prevention and treatment rests with improving intervention strategies aimed at strengthening PFC inhibitory systems among at-risk individuals.

Figure 1

Illustrations showing medial prefrontal cortex (in red), anterior cingulate cortex (in yellow) and orbitofrontal cortex (in gray) in rat brain viewed in coronal and sagittal planes. Abbreviations: OB, olfactory bulb; Cb, cerebellum; lfh, longitudinal fissure of hemisphere; cc, corpus callosum; ac, anterior commissure; CPu, caudate putamen; LV, lateral ventricle; Th, thalamus; Hi, hippocampus. Figure based on Dalley et al. (2004) and Paxinos and Watson (2005).

Figure 2

Illustrations showing medial prefrontal cortex (in red), lateral prefrontal cortex (in blue), anterior cingulate cortex (in yellow) and orbitofrontal cortex (in gray) in human brain viewed in dorsal, ventral, coronal and sagittal planes. Abbreviations: OB, olfactory bulb; Cb, cerebellum; lfh, longitudinal fissure of hemisphere; Oc, occipital cortex; cc, corpus callosum; ox, optic chiasm; Hy, hypothalamus; py, pyramidal tract; po, pons. Figure based on Mai et al. (1997).