Abstract: The n-back task with or without monetary reward was used to explore the effect of monetary reward on the refresh function of working memory in heroin abstainers. The mixed experimental design of 2 (subjects type: normal group, heroin withdrawal group) × 2 (task type: 1-back, 2-back) × 2 (reward type: no reward, monetary reward) was adopted, in which the subjects type was the inter group variable, task type and reward type was the intra group variable, and the dependent variable index was the reaction time and correct rate of correct response. Thirty two male heroin abstainers were selected from a compulsory isolation and rehabilitation center in Gansu Province, and 34 normal male subjects were recruited. There was no significant difference in age and years of education between the two groups. At the beginning of the program, the computer screen will display a guide to tell the subjects whether they will be rewarded after the task operation and the following tasks are completed. When the subjects fully understand the task and press "Q" key to start, a 500ms letter stimulus will appear in the center of the computer screen, followed by a 2000ms blank screen, followed by a 500ms letter stimulus. The subjects are required to judge the current thorns Whether the stimulation is the same as the last n stimulation? Press the "F" key. Otherwise, press the "J" key. Press the key quickly and accurately. No reward and monetary reward conditions adopt block design. If it is an n-back task under the condition of monetary reward, each time the subjects respond correctly, the experimental program will automatically record and add a point in the background, and the reaction error will not increase the point. The more points the subjects get, the more reward they will eventually get. In the process of task operation, the subjects are not ed whether the reaction is correct or not and the number of points obtained. Only during the break and after the experiment, the computer screen will display the current total number of points obtained; n-back tasks without reward will not be recorded or fed back. The results of repeated measurement analysis of variance showed that (1) the response time of all subjects under the condition of monetary reward was significantly shorter than that under the condition of no reward; (2) the difference between the response time of heroin withdrawal group under the condition of monetary reward or not was significantly smaller than that of the normal group under the condition of monetary reward or not; (3) in the 1-back and 2-back tasks, the correct rate of the normal group was significantly higher than that of heroin withdrawal group. The results show that monetary reward can promote the updating function of working memory of heroin abstainers, but the extent of its promotion is weaker than that of normal people; the updating function of working memory of heroin abstainers may be damaged.

Key words: heroin abstainers, updating of working memory, monetary reward

摘要： 采用有无金钱奖赏条件下的n-back任务，探讨金钱奖赏对海洛因戒断者工作记忆刷新功能的影响。结果发现：所有被试在金钱奖赏条件下的反应时都显著短于无奖赏条件下的反应时；海洛因戒断组在有无金钱奖赏条件下的反应时的差值显著小于正常组在有无金钱奖赏条件下的反应时的差值；在1-back和2-back任务中，正常组的正确率显著高于海洛因戒断组的正确率。结果表明：金钱奖赏对海洛因戒断者工作记忆刷新功能存在一定的促进作用，但是其促进作用幅度要弱于正常人；海洛因戒断者的工作记忆刷新功能可能存在损伤。

关键词: 海洛因戒断者, 工作记忆刷新, 金钱奖赏