The loss of behavioral control that underlies addiction has at least 2 components, decreased frontal cortical regulation of attention and cognitive flexibility and increased limbic fear-negative feelings (Fig. 1). The frontal lobes of brain are involved in decision making and other executive functions such as motivation, planning, goal setting and inhibition of impulses. Frontal lobe functions also predict future consequences, choose between good and bad actions (or better and best), override and suppress unacceptable social responses, and determine similarities and differences between things or events. The frontal lobes also play an important part in retaining long term emotional memories and adjusting emotions to fit socially acceptable norms important for individual integration into society. Frontal behavioral control mechanisms block impulsive mistakes and predict future rewards (Schoenbaum and Shaham 2008). Loss of these functions is a key element of the neurobiology of addiction and substance dependence (Fig. 1).
