AN EVOLUTIONARY PERSPECTIVE ON SUBSTANCE-ABUSE

This article describes how recent advances in understanding the evolut ionary functions of emotions can help to reconcile diverse approaches to substance abuse. Emotions can be understood as specialized states t hat prepare individuals to cope with opportunities and threats. Drugs that artificially induce pleasure or block normal suffering disrupt th ese evolved mechanisms, and thus should tend to interfere with adaptiv e behavior, even if the drugs are medically safe. Nonetheless, we rout inely use drugs quite safely to block defenses like pain, cough, and a nxiety. This apparent contradiction is explained by the relatively sma ll costs of defenses compared to the potentially huge costs of not exp ressing a defensive response when it is needed. An evolutionary perspe ctive has implications for substance abuse research, treatment, and so cial policy. This perspective suggests that the search for etiology ne eds to address the human tendency to abuse drugs separately from indiv idual differences in these tendencies, that clinical treatments that t ake account of the broad range of patients' emotional life are well ju stified, and that social policies need to address substance use and ab use not as diseases to be cured but as human tendencies that need to b e managed. To prepare for future drugs that will likely alter emotions safely, we urgently need a better understanding of the adaptive funct ion of the emotions.