Drug Stroop performance: Relationships with primary substance of use and treatment outcome in a drug-dependent outpatient sample

A modified Stroop protocol was administered to a sample of 80 dependent drug users (62 males, 18 females) prior to beginning a time-limited outpatient treatment study combining pharmacotherapy and cognitive–behavioral coping skills therapy for cocaine, marijuana, or heroin dependence. Results indicated that cocaine-dependent participants responded more slowly than marijuana-dependent participants to all stimulus words. Cocaine words yielded slower reaction times than neutral words across all treatment groups. The heroin- and cocaine-dependent groups' overall performance did not differ. There was no treatment group by drug word interaction. For cocaine-dependent participants, Stroop performance in the presence of cocaine stimuli was associated with worse treatment outcome. In conclusion, Stroop performance may have prognostic utility among drug-dependent patients in a cognitive–behavioral coping skills intervention and may highlight the mechanisms associated with changing substance use in this treatment modality.