戒断期海洛因依赖者额叶认知功能的功能磁共振成像研究

目的 研究戒断期海洛因依赖者(AHD)的脑认知功能.方法 采用3.0 T磁共振成像系统,对30例AHD(AHD组)和18名健康对照者(对照组)在完成Go/NoGo任务时行全脑功能磁共振成像(fMRI)扫描,记录反应时间(RT).结果 (1)RT:AHD组在完成Go/NoGo任务时的RT[(394±34)ms]长于对照组[(374±26)ms;P<0.05].(2)fMRI:对照组在完成Go/NoGo任务时,诱发激活双侧前额叶内侧回、前扣带回以及双侧额下回等脑区;AHD组全脑活动普遍低,仅有双侧额上回和左侧额中回激活.两组间比较,AHD组激活显著低于对照组的区域主要位于在双侧额内侧回、前扣带回、额下回及双侧颞叶等脑区(P<0.005).结论 戒断期海洛因依赖者反应抑制功能障碍仍然存在,促进其认知功能的恢复可能成为戒毒、抗复吸的有效策略.

Impaired cognitive function in abstinent heroin addiction: an ftmetional magnetie resonance imaging study

Objective To probe the frontal neurecognitive function in patients with abstinent heroin addiction (AHD) during a Go/NoGo task and to explore the mechanism of addiction. Methods Thirty AHD patients and 18 healthy controls were recruited in the study, with no significant differences in age (33±6 year vs. 29±7 year) and education (10.8±2.2 year vs. 9.9±2.3 year). All subjects were received fMRI-BOLD scan when they performed a Go/NoGo task, which was in a block-design and could provide a direct, but simple paradigm to investigate the response inhibition function. Reaction times (RT) were recorded spontaneously. Results Neural response induced by response inhibition was prominent in the midline structure, specifically the bilateral medial prefrontal gyrus (mPFC) and anterior cingulated cortex (ACC), as well as the bilateral inferior frontal gyms (IFG). Unlike controls, the whole brain response decreased and only the bilateral superior frontal gyrus and left middle frontal gyms were significantly activated in AHD. Furthermore, the RT of AHD was significantly longer than that of controls [(394±34) ms vs. (374±26) ms ]. Conclusions The results suggest that heroin dependents have an impaired frontal execution function that lasts months into abstinence, which indicates the negative effect of herein on the inhibitory control still continues in early protracted withdrawal state. Enforcing prefrontal cognitive function and improving self-centrol may potentially prolong abstinence and prevent relapse.