Abstract: Abstract Drug addiction is a chronic relapsing disorder characterized by compulsive drug use, despite a series of serious negative consequences for personal and social. This characteristic of this population indicates that drug addiction may be associated with decision-making defects. A large number of experimental results have demonstrated that drug users are more inclined to choose high rewards with small probability compared with small rewards with high probability in decision-making under risk. However, little research has been designed to investigate the impact of decision-making frame (gains vs losses) on decision-making under risk of substance users. This study aim to dissociate the risky decision making pattern of heroin abstainers under reward and loss condition. Especially considering the low education degree for heroin addicts in China and deficits in executive function, we used a novel gambling task (toronto gambling task, TGT) to assess specific abnormal decision-making behavior under two different frames. Seventy participants (35 male heroin users during their abstinence period and 35 normal controls) performed a modified version of TGT to investigate whether heroin abstainers’ risky decision-making behavior was modulated by reward and loss conditions. This gambling task was consisted of five cards in each trial. One of the five cards displayed a gold ingot/ bomb on it, whereas the other cards were blank. Participants were instructed to find the card with the gold ingot in reward condition and avoid the card with the bomb in loss condition. Participants were asked to select a number of cards ranging from one card up to five cards. In addition, there were two order conditions in this gambling task (“Add” and “Subtract”). In the “Add” condition, card was added to the display from left to right, and the time interval for each card is 2 s; In the “Subtract” condition, all five cards were initially presented and the cards disappeared every 2 s from right to left. Participants were asked to press the space bar when they wanted to make a choice. The results showed that the main effect of group was significant, heroin abstainers overall had more risk-seeking behavior than control group; the main effect of the decision-making condition was also significant, all subjects had higher risk-seeking behavior under loss condition campared with reward condition. However, the interaction between group and decision-making condition was not significant. Besides, the rate of making a risk-seeking choice in heroin abstainers was found positively related with years of heroin use under the loss condition, while this corelation was not found under the reward condition. The further regression analysis found that the high proportion of risk-seeking decision in heroin abstainers could have been caused by the low risk-aversion tendency after negative feedback when they choose those high-risk options. Heroin abstainers showed a higher risk-seeking tendency than control group, this result again verifies the risky decision-making defects of substance addicts found in previous studies. The positive correlation between risk-seeking tendency and the years of heroin use may indicate decreased loss sensitivity in heroin abstainers, which may be further exacerbated by sustained drug using. The risk-aversion tendency of heroin abstainers when they received negative feedback after making risky decisions negatively predicted their risk-seeking tendency, this may reflect decreased sensitivity for risk or abnormal processes involved in integrating penalty information for the purpose of response selection. Further research is needed into the links between those deficits in decision-making under risk and compulsive drug-seeking behavior and relapse of heroin users. In addition, whether gender differences may affect the risky decision-making patterns of heroin abusers in different decision-making condition is also a question worth further exploring.

Key words: Key words heroin abstainers, risky decision-making, reward condition, loss condition

摘要： 摘 要 采用修改版的多伦多赌博任务考察决策情境对海洛因戒断者风险决策的影响。研究结果主要发现，海洛因戒断者在损失情境下的风险寻求决策比率与吸毒年限显著正相关，这种相关提示了风险决策背景下海洛因成瘾者持续使用毒品与其较低的损失敏感性之间的复杂交互作用。其次，海洛因戒断者在做出风险决策后收到消极反馈时的风险规避倾向可以负向预测其风险寻求决策比率，这可能进一步反映了海洛因戒断者风险感知的钝化或其对消极反馈信息的整合加工存在异常。

关键词: 关键词 海洛因戒断者, 风险决策, 奖赏情境, 损失情境