伴发抑郁海洛因依赖者执行反应抑制任务及静息态功能磁共振研究

Heroin dependence is one of the most severe public health problems in China and all over the world. It is very common that other psychotic diseases co-occur with heroin dependence, which makes the prognosis of heroin addicts poorer and with higher risk of relapse. To our best knowledge, we have not found any studies regarding heroin addicts with depression using functional Magnetic Resonance Imaging (fMRI). Whereas， fMRI has been being one of the most important techniques to probe the mechanism of heroin dependence. The focus of early stage is rewarding and craving with task-based fMRI. Whereas now decision making, response inhibition become the focus. The deficit of response inhibition is close related to impulsive drug seeking. Resting-state fMRI, which can be used to show the brain connectivity, is becoming the hot points due to no task required, no invasion and repeatable. However, those fMRI studies, either response inhibition or resting-state fMRI, mainly focus on the comparison between heroin addicts and healthy control. Therefore, we decided to explore the difference between heroin addicts with and without depression. Our pilot study showed the tendency of longer reaction time in heroin addicts with depression, compared to no depression heroin addicts. The activations of both task-based and resting-state fMRI are also somewhat different between the two groups. So, in order to provide personal treatment and decrease relapse rate among heroin addicts, it is worthwhile to deeply explore the differences between heroin addicts with and without depression by fMRI.

海洛因依赖是我国及世界严重的公共卫生问题之一。海洛因依赖患者中伴发其它精神障碍很常见。其中，抑郁是最常伴发的精神障碍之一，严重影响海洛因依赖的治疗和预后，也是复吸的主要因素之一。目前尚未检索到用功能磁共振技术对伴发抑郁海洛因依赖的研究。而功能磁共振技术一直是探讨海洛因成瘾机制的主要手段之一。基于任务态的功能磁共振早期研究的焦点是奖赏和渴求，而目前焦点则是成瘾者的反应抑制、决策等。由于无需任务，静息态功能磁共振近年来成为研究热点。但目前功能磁共振研究主要是在海洛因依赖者和正常对照之间的研究。因此，我们决定对伴发抑郁海洛因依赖者进行任务态和静息态功能磁共振研究。我们的预实验显示，与不伴抑郁海洛因依赖者相比，伴抑郁海洛因依赖组的反应抑制能力有减弱的趋势。任务态和静息态功能磁共振上两组均可能存在差异。因此，为海洛因依赖的个体化治疗和降低复吸，值得对伴发抑郁海洛因依赖的机制进行深入研究。

抑郁是海洛因依赖患者中最常伴发的精神障碍之一，严重影响海洛因依赖的治疗和预后，也是复吸的主要因素之一。功能磁共振技术一直是探讨海洛因成瘾机制的主要手段之一。我们课题组对海洛因依赖者人群中，伴及不伴抑郁的患者进行了认知和功能磁共振研究。本研究发现，1.海洛因依赖者中，无论相容性还是不相容性刺激，抑郁导致海洛因被试者执行SRC任务时，所需的反应时明显增高，差异有统计学意义。表明，海洛因依赖影响了患者的反应抑制功能，而抑郁可能加重了对海洛因依赖患者反应抑制功能的影响，对患者的认知损害起到了叠加的作用。2.任务态功能磁共振研究显示，与不伴抑郁海洛因依赖组相比，伴抑郁海洛因依赖组的辅助运动区和基底节区激活明显。增加的脑区激活，提示伴抑郁海洛因依赖组反应抑制能力下降，执行反应抑制任务时需要更多脑区的参与也提示是一种脑内资源的浪费。3.伴抑郁海洛因依赖组的脑功能异常区域可能以前额叶为主，而不伴抑郁海洛因依赖组的脑功能异常区域可能以顶叶为主。4.静息态功能连接结果显示，与不伴抑郁海洛因依赖组相比，伴抑郁海洛因依赖组功能连接减弱的脑区主要在前扣带和前额叶内侧皮层。提示可能是抑郁和海洛因依赖共同作用的结果。可见，伴抑郁海洛因依赖者涉及到更加复杂的脑功能网路系统以及其间的功能连接异常。今后值得从海洛因依赖、抑郁和认知功能之间的关系，进一步探讨有效的干预海洛因依赖的手段。