The Impulsive Behavior In Heroin Abstainers

The behavior impulsivity is the core characteristic in drug dependent individuals. Currently, two main research approaches have been proposed in studying drug dependent individuals' impulsive behavior, namely the gambling paradigm basing on the somatic marker hypothesis and the delay discounting paradigm basing on behavior economics. The present study had explored the reaction patterns and their relationship in risk-decision situations and delayed reinforcement ones in heroin abstainers basing on across paradigms research strategies. This research is of great significance not only for integrating the two approaches and exploring the structure and its dynamic development of impulsive behavior in drug dependent individuals, but also for clinical practice in evaluating and promoting the efficiency of drug abstinence.In the present study, three experiments were conducted to explore the impulsive reaction patterns and their relationship in risk-decision situations and delayed reinforcement ones during different abstinence phases in heroin abstainers. The main results are as follows:(1) The impairment of decision making function in win-risk coincidence situations in heroin abstainers was demonstrated in their immediate win-priority selecting pattern and the tolerance to high risk.(2) The impairment of decision making function in delayed reinforcement situations in heroin abstainers was manifested in their hyposensitivity to immediate reward and their insensitivity to delayed value, which led to the quick decay of long-time value.(3) The Iowa Gambling Task (IGT) was more sensitive to heroin abstainers' tolerance to risk, while the Delay Discounting Task (DDT) was more efficient in evaluating their insensitivity to long-term value, both of which corresponded with two key variables of decision making, namely risk and delay, respectively.(4) The behavioral impulsivity in heroin abstainers did not improve along with abstinence time course.