Impaired decision-making in psychopathic heroin addicts.

Substance-dependent individuals (SDIs) often show neurocognitive deficits in decision-making, such that their choices are biased toward the greatest immediate reward rather than the optimal future outcome. However, studies of SDIs are often hampered by two significant methodological challenges: polysubstance dependence and comorbid conditions, which are independently associated with neurocognitive impairments. We addressed these methodological challenges by testing heroin addicts in Bulgaria, where heroin addiction is highly prevalent but polysubstance dependence is rare.