健康与遗传心理学研究室知识库

药物依赖是以强迫性觅药、用药以及戒断后的复吸为主要特征的慢性脑疾病。复吸（relapse）既是药物依赖的主要特征，也是临床治疗的首要问题。反复用药的成瘾个体一旦被戒除药物，会表现出一系列负性情绪，如快感缺失（anhedonia）、烦躁（dysphoria）、易激惹（irrirability）和焦虑（anxiety）等，个体往往为缓解负性情绪而再次用药。即使经过长期戒断，这种负性情绪状态仍然可能是影响个体发生复吸的重要因素。但研究发现，快感缺失存在于药物戒断短期，随着戒断时程的延长，快感缺失状态逐渐恢复甚至消失。众所周知，即使已经脱毒的成瘾个体仍然存在较高的复吸风险，而应激就是诱发复吸的重要因素之一。那么，研究药物戒断个体在遭遇应激事件后其奖赏系统的功能状态将有助于理解复吸行为发生的心理过程和机制，也会对复吸的预防与治疗有所帮助。然而目前关于药物长期戒断个体经历应激之后对自然奖赏的反应和动机行为的研究鲜有报道。 本研究使用能够诱发严重戒断症状的大剂量吗啡模型，主要探究吗啡长期戒断（约为戒断后 14-20  天）动物应激后对多种自然奖赏物（两种浓度糖水、性）消耗、趋近和强迫性样行为的影响。研究发现：
1.在长期戒断中，应激会引起动物（吗啡前处理和盐水前处理）对糖水（4%浓度）的消耗下降，表现出快感缺失样症状。但对高浓度糖水的消耗、FR1、PR行为无显著影响。应激也下调动物对60%浓度糖水的强迫样行为。
2.  在戒断长期，应激并不会引起动物对性奖赏的趋近、努力相关行为，即应激并不会引起动物对性奖赏的快感缺失症状。但在动物的冒险性行为中，应激上调盐水前处理动物的冒险行为，并下调吗啡前处理动物的冒险性行为。

Drug addiction  is a chronically relapsing disorder characterized by compulsion  to seek and take the drug. Relapse is both a major feature of drug addiction and a primary concern for clinical treatment. Repeatedly addicted individuals, once removed from the drug, will show a series of negative emotions, such as anhedonia, dysphonia, irrirability, and anxiety. Individuals tend to re-use addictive drugs to relieve negative emotions. Even after prolonged withdrawal, this negative emotional state may still be an important factor affecting the individual's relapse. However, the study found that the  anhedonia  in the short-term withdrawal of drugs, with the withdrawal of the extension of time, the anhedonia gradually restored or even disappear. As we all know, even if the detoxification of the addictive individuals still have a high risk of relapse, and stress is one of the important factors  to  induce relapse. Then, the study of drug withdrawal of individuals in the event of stress after the reward system of its functional status will help to understand the psychological process and mechanism of relapse behavior, but also on the prevention and treatment of relapse. However, there are few reports on the response and motivations of natural reward after the long-term withdrawal of drugs. In this study, a binge-like regimen of morphine administration was used to induce severe withdrawal symptoms,  then, we investigated consummatory, approaching and compulsive-like responses for food and sex rewards during  long-term withdrawal phases  (about 14-20 days after withdrawal) after acute stress. The study found:
1. In long-term withdrawal, stress causes a decrease in consumption of  sucrose  (4%) in animals (pretreatment of morphine and pretreatment of saline), showing  anhedonia. But had no significant effect on FR1 and PR behavior of high concentration sucrose. Stress also reduced the animal's compulsive-like behavior on 60% sucrose.
2. In the long-term withdrawal, stress does not lead to  animal sexual reward approaching, effort-based behavior, that is, stress does not cause the anhedonia. However, in animal risk-taking behavior, stress increases the risk-taking behavior of saline pretreatment animals but reduces the risk-taking behavior of morphine pretreatment animals.