不同相关线索下海洛因成瘾者的反应差异及反应抑制特征：来自ERP的证据

采用ERP技术, 探究海洛因成瘾者在不同相关线索下的脑电反应及其与冲动性的关系。实验采用组间实验设计和双选择Oddball范式, 要求海洛因成瘾组和健康对照组被试对标准刺激与偏差刺激分别做不同的按键反应, 记录他们的EEG数据。结果发现：相比对照组被试, 海洛因成瘾者在观看药物相关线索时诱发的N2波幅更小, P3波幅更大; 在成瘾组内, 相比用药工具线索, 用药动作线索诱发了更小的N2波幅和更大的P3波幅。这表明海洛因成瘾者对药物相关线索存在反应抑制缺陷, 且不同的药物相关线索会激发海洛因成瘾者不同程度的反应抑制缺陷, 用药动作线索比用药工具线索更大程度地影响成瘾者的反应抑制能力, 反映出更高的动作冲动性。

Differences in brain reactivity in relation to different types of drug-associated cues and disinhibition among heroin addicts: An ERP study

Persons who are addicted are known to show cue-induced responses (such as psychological craving) to drug-related cues. Previous research showed that both tool-related (e.g., syringe) and action-related (e.g., use of the syringe) drug cues can elicit craving. However, whether the two types of drug related cues can elicit the same brain reactivity and similar degree of disinhibition is still unclear, especially because of the scarcity of ERP studies on this topic. Using a behavioral task and the ERP technique, the present study investigated the behavior reactivity and EEG characteristics shown by men addicted to heroin and healthy controls in response to tool-related and action-related drug cues. Participants were 36 men, 19 of whom were addicted to heroin and 17 of whom were healthy non-drug users, matched on age and years of education. Participants engaged in the two-choice Oddball task, which included two conditions: A. the tool condition, with a picture of a “cup” serving as the standard stimulus and pictures of drug-use tools serving as deviant stimuli; B. the action condition, with a picture of “drinking water” serving as the standard stimulus and pictures of drug-use actions serving as deviant stimuli. In this experiment, the probabilities of standard stimuli and deviant stimuli were 70% and 30%. Participants were asked to press different keys on the keyboard in response to standard stimuli and deviant stimuli as rapidly and accurately as possible. Behavioral results indicated that in men who were addicted to heroin, greater disinhibition was seen in a longer reaction time in response to action cues than tool cues. Between-group analyses of the ERP data showed that compared to the healthy controls, men who were addicted to heroin demonstrated a smaller N2 and larger P3 amplitude in response to drug related cues. Moreover, action cues elicited a smaller N2 amplitude in the heroin addicted group than the control group, especially in the frontal, central and central-parietal areas of the brain, and a larger P3 amplitude, especially in the central and parietal areas of the brain. Within-group analyses in just the heroin addicted group showed that the N2 was smaller in response to action cues versus tool cues. Meanwhile, the action cues elicited a larger amplitude of P3 than the tool cues, especially in the central, central-parietal and parietal regions of the brain. These findings provide behavioral and ERP evidence for the hypothesis that different types of drug-related cues produce different cue-induced reactivity. More specifically, drug use action stimuli, which appear to trigger greater disinhibition and greater ERP reactivity in the brain areas associated with motor resonance, should be considered in the treatment of addiction and in relapse prevention.