Temporal discounting in heroin-dependent patients: no sign effect, weaker magnitude effect, and the relationship with inhibitory control.
Impulsive behavior in heroin-dependent individuals and matched smokers was studied within the framework of temporal discounting. Two well-known effects were examined: the sign and magnitude effects (Kirby, 1997). The study also investigated the relationship between cognitive impulsivity and inhibitory control as measured by a Go/No-go task. Fifty-six heroin-dependent patients in the postmethadone treatment stage and an equal number of matched daily smokers participated in the study. The heroin-dependent patients showed higher discount rates in both gain and loss conditions. They also showed no sign effect by demonstrating similar discount rates in gains and losses. Heroin-dependent patients also exhibited a magnitude effect, which was weaker than that observed in smokers. Differential relationships between impulsivity and inhibitory control were found in the two groups. For smokers, decision-making and inhibitory control behaviors pertained to different psychological processes, whereas for heroin-dependent patients, the two behaviors were partially related. Finally, a significant correlation between length of heroin use and temporal discounting with small magnitude was found. The present study advances our understanding of the specific behavioral impulsive patterns in heroin-dependent individuals.
Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
Jiuqing
J
Cheng
Yanhong
Y
Lu
Xiaodong
X
Han
Claudia
C
González-Vallejo
Nan
N
Sui
D000328:Adult; D016022:Case-Control Studies; D003657:Decision Making; D005260:Female; D006556:Heroin Dependence / Q000523:psychology* / Q000534:rehabilitation; D006801:Humans; D007175:Impulsive Behavior / Q000209:etiology*; D007266:Inhibition, Psychological; D008297:Male; D008691:Methadone / Q000008:administration & dosage; D058850:Opiate Substitution Treatment / Q000379:methods; D012907:Smoking / Q000523:psychology*
D008691:Methadone