Chapter 11 - Individual Differences in Response to Stress and Risk for Addiction

Abstract

Alcoholism is known to run in families, raising the question of genetic contributions and the person's susceptibility to environmental factors, including life stress. This chapter presents selected data on persons with a family history of alcohol or drug abuse (FH+) and discusses altered limbic system function and response to stress that may underlie their propensity toward addiction. In such persons, the limbic system and prefrontal cortex are seen to undergo neural plasticity during times of emotional distress and also in response to drug intake, and these processes are therefore seen as having a common impact on the vulnerable individual. Addictions are more common in persons with a family history of substance use disorders (FH+), suggesting an inherited disposition. FH+ persons also have a tendency toward behavioral undercontrol, characterized by antisocial behaviors, excitement seeking, impulsivity, and poor mood regulation. FH+ have a blunted stress cortisol response, but they respond positively to pharmacological challenge with opioid receptor blockers. These findings are consistent with a hypothesis that FH+ have a chronically enhanced central opioid activation. The val158met polymorphism of the catechol-O-methyltransferase gene may underlie these risk-associated characteristics. The polymorphism is more common among patients with substance use disorders than in healthy controls.