Using cognitive modelling to investigate the psychological processes of the Go/NoGo discrimination task in male abstinent heroin misusers.

AIMS To use cognitive modelling to investigate psychological processes underlying decision-making in male abstinent heroin misusers (AHMs). DESIGN A case-control study design. SETTING A drug misuse treatment centre in Taiwan. PARTICIPANTS Eighty-eight male AHMs and 48 male controls. MEASUREMENTS Four parameters representing the attention to wins, learning rate, response sensitivity and incentive of heroin-related stimuli from the modified Go/NoGo discrimination task. FINDINGS A modified cue-dependent learning (CD) model with four parameters representing attention to wins, learning rate, response sensitivity and incentive of heroin-related stimuli had a lower value of the sum of Bayesian information criterion (showing a better fit) than the original CD model (9555.50 versus 11,192.22, P < 0.001). The AHM group had a higher value of the heroin-incentive parameter than the control group (0.26 versus -1.66, P < 0.05). The attention to wins and heroin-incentive parameters were associated positively with total commission rate and negatively with total omission rate in the AHM group (P < 0.001). CONCLUSIONS Male abstinent heroin misusers appear to be more influenced by heroin-related stimuli during decision-making than males with no history of heroin misuse.