海洛因戒断者对金钱奖赏的反馈加工异常：来自ERP的证据

本研究采用金钱奖赏延迟任务考察了海洛因戒断者对金钱奖赏和损失的预期和反馈加工及其电生理机制。结果发现,预期阶段两组被试由不同线索诱发的P3波幅不存在显著性差异。在金钱奖赏加工的反馈阶段,海洛因戒断组由金钱收益条件诱发的RewP波幅显著小于对照组由金钱收益条件诱发的RewP波幅,而在无收益无损失条件下两组被试诱发的RewP波幅不存在显著性差异。此外,海洛因戒断组由金钱收益条件诱发的P3波幅与无收益无损失条件诱发的P3波幅不存在显著性差异,而对照组由金钱收益条件诱发的P3波幅显著大于其由无收益无损失条件诱发的P3波幅。在金钱损失加工的反馈阶段,由金钱损失和无收益无损失条件诱发的RewP波幅在两组被试之间不存在显著性差异,且两组被试由金钱损失条件诱发的P3波幅均显著大于其由无收益无损失条件诱发的P3波幅。以上结果说明海洛因戒断者的金钱奖赏反馈加工存在异常,具体表现为其对金钱奖赏的敏感性降低或对金钱奖赏的趋近动机减弱。     

网络游戏成瘾与海洛因成瘾存在相同的神经机制吗?——基于MRI的证据

网游成瘾与海洛因成瘾具有许多相似的临床表现,但其神经机制是否相同还不得而知。综合近5年来的MRI研究发现,两类成瘾存在部分相同区域的脑结构和功能损害,且在成瘾线索诱发下二者的4个成瘾相关环路(认知控制环路、奖赏环路、动机环路和记忆-学习环路)均出现了广泛而增强的脑区激活反应。但海洛因成瘾的脑损害区域偏向更高级的认知控制环路和奖赏环路,损害范围也更广(4个环路的功能连通性均降低),而网游成瘾的脑损害主要发生在相对低级的记忆-学习环路和动机环路,损害范围也较窄(功能连通性降低只发生在认知控制和记忆-学习环路之间)。这些结果说明,两类成瘾行为的神经机制既有相同点,又有差异性。     

海洛因戒除者对相关线索和负性生理线索的注意偏向

以84名海洛因戒除者和20名正常成人为被试,采用情绪stroop范式探讨了不同康复时相海洛因戒除者对海洛因相关线索和负性生理线索的注意偏向。结果发现,海洛因戒除者对表征与海洛因滥用相关的负性生理线索和表征海洛因使用行为的相关线索存在同等效力的注意偏向,且在不同康复时相内具有稳定性。该研究为解释基于戒除症状的负性情绪对于诱发依赖者药物渴求感和复吸行为的作用及整合基于对相关线索注意偏向的认知加工理论和基于对负性情绪的回避的负强化情绪加工理论提供了实验证据。     

Randomized Trial Comparing Two Treatment Strategies Using Prize-Based Reinforcement of Abstinence in Cocaine and Opiate Users

We compared two strategies of prize-based contingency management (CM) in methadone-maintained outpatients. Urine was tested thrice weekly for 5 weeks pre-CM, 12 weeks CM, and 8 weeks post-CM. Participants were randomly assigned to a cocaine contingency (four prize draws for each cocaine-negative urine, N  =  29) or an opiate-cocaine contingency (one draw for each urine negative for opiates or cocaine, four draws if negative for both, N  =  38). There were no group differences in cocaine abstinence during CM or post-CM and no differences in opiate abstinence during CM. Opiate abstinence was greater in the opiate-cocaine group post-CM, and heroin craving was reduced in this group during and post-CM. Draws earned per cocaine-negative urine (four vs. one) did not affect cocaine use.     

A BEHAVIORAL INTERVENTION FOR IMPROVING VERBAL BEHAVIORS OF HEROIN ADDICTS IN A TREATMENT CLINIC

Positively reinforcing appropriate behaviors improved verbal behaviors of opioid-dependent patients in a buprenorphine treatment clinic. During B phases of an ABAB design, clients received stickers for engaging in appropriate verbal or nonverbal behaviors. Each sticker provided a chance of winning $25. No reinforcement was provided during the A phases. Appropriate verbal behaviors increased during reinforcement periods, and inappropriate verbal behaviors decreased.     

海洛因戒除者的行为冲动性： 基于DDT和IGT任务反应模式的探讨

以61名男性海洛因戒除者和32名正常成年男性为被试,探讨了海洛因戒除者在延迟折扣任务和Iowa赌博任务两种决策条件下的冲动性反应模式及其关系。结果发现,海洛因戒除者的决策行为受其对即时强化的超敏感性或“即时收益优先”模式控制,其高冲动性特质既表现为对强化物长远价值的非敏感性,又表现为对强化物潜在风险的耐受性;该类人群上述两方面的特征虽有一定关联,但二者分别反应了其行为冲动性的两个相对独立的维度,且具有跨戒除时相的相对稳定性     

海洛因戒治者对疼痛线索的选择性注意加工偏向

研究采用点探测范式,以疼痛线索(感觉疼痛词、情感疼痛词和健康灾难词)和中性线索(中性词)为实验材料,考察接受美沙酮维持治疗的海洛因戒治者对疼痛线索的视觉选择性注意偏向。结果表明:海洛因戒治者对疼痛线索的注意偏向具有普遍性,即对感觉疼痛词、情感疼痛词和健康灾难词等三类疼痛线索均存在注意回避偏向,尤其对健康灾难词的注意回避程度最高;海洛因戒治者还对感觉疼痛词和情感疼痛词存在注意脱离易化倾向。本研究对于有针对性的开展注意偏向矫正以干预疼痛,从而辅助美沙酮的治疗效果、维持患者的戒断状态、降低其复吸风险具有重要意义。     

Purchase task sensitivity to drug and nondrug reinforcers in opioid-agonist treatment patients

The behavioral economics of substance abuse has been increasingly recognized as a method of determining the value of abused substances for individuals who use those substances. It has been hypothesized that such analyses could serve as a clinical tool and that demand functions can be targeted predictors for the level of intervention necessary. This study evaluated the sensitivity of a demand task in 2 patient groups in a medication assisted treatment program (methadone maintenance), those who had used opioids in the last 2 months and those who had not used opioids in at least 18 months. Demand for 7 drugs and a control was assessed using hypothetical purchase tasks. Participants maintaining long-term abstinence had significantly higher α (sensitivity to price) and lower Q₀ (intensity of demand) for heroin than participants who had recently used opioids. Further research is necessary to illustrate if treatment is responsible for this reduction in demand. If so, demand analyses may provide clinical utility as an aid for treatment planning or as a target for treatment.     

长期戒断海洛因成瘾者冲动性相关脑区的结构及功能特征

冲动性是药物成瘾者的典型特征, 它既包含了抑制控制成瘾者药物使用的力量, 也包含驱动成瘾者使用药物的成分, 两者不平衡导致冲动性用药行为。海洛因成瘾者本身具有冲动性人格特质, 长时间的海洛因使用又会造成成瘾者冲动性相关的大脑结构与功能的异常。目前难以确定戒断后, 冲动性及相关的大脑结构与功能是否还呈异常状态。本研究采用基于体素的形态学分析、低频振幅、局部一致性和功能连接方法, 以35例海洛因成瘾戒断者和无任何成瘾史的健康个体26人为研究对象, 探索在长期戒断后, 海洛因成瘾者与其冲动性相关的驱动、控制系统脑网络的结构和功能情况。结果显示, 相比对照组, 戒断组灰质总体积及右内侧额上回的灰质体积显著减小, 右侧颞中回和左内侧旁扣带回的灰质体积随用药总量的增加而降低; 右侧眶部额下回与尾状核功能连接显著增强, 右侧颞中回和左侧中央前回功能连接显著降低; 右眶额中回的ReHo值、右眶额下回和左海马体的ALFF值比对照组显著更低, 而右中央后回的ReHo值显著更高。这些脑区的状况与冲动性的神经基础相吻合, 说明海洛因成瘾戒断者在戒断44个月, 奖赏、凸显、习惯性行为等网络系统仍然呈现异常状态, 且与成瘾药物使用总量有关。这些异常可能是成瘾冲动性的驱动力的神经基础, 可以作为解释成瘾者戒断后容易复吸的因素之一。