Schoenbaum Geoffrey, Shaham Yavin
Department of Anatomy and Neurobiology, University of Maryland, School of Medicine, Baltimore, Maryland 21201, USA.
Biol Psychiatry. 2008 Feb 1;63(3):256-62. doi: 10.1016/j.biopsych.2007.06.003. Epub 2007 Aug 23.
Studies using brain imaging methods have shown that neuronal activity in the orbitofrontal cortex, a brain area thought to promote the ability to control behavior according to likely outcomes or consequences, is altered in drug addicts. These human imaging findings have led to the hypothesis that core features of addiction like compulsive drug use and drug relapse are mediated in part by drug-induced changes in orbitofrontal function. Here, we discuss results from laboratory studies using rats and monkeys on the effect of drug exposure on orbitofrontal-mediated learning tasks and on neuronal structure and activity in orbitofrontal cortex. We also discuss results from studies on the role of the orbitofrontal cortex in drug self-administration and relapse. Our main conclusion is that although there is clear evidence that drug exposure impairs orbitofrontal-dependent learning tasks and alters neuronal activity in orbitofrontal cortex, the precise role these changes play in compulsive drug use and relapse has not yet been established.
运用脑成像方法的研究表明，眶额皮质中的神经元活动在吸毒成瘾者身上发生了改变。眶额皮质是大脑中的一个区域，被认为有助于根据可能的结果或后果来控制行为的能力。这些人体成像研究结果引发了一种假说，即成瘾的核心特征，如强迫性药物使用和药物复吸，部分是由药物引起的眶额功能变化所介导的。在此，我们讨论使用大鼠和猴子进行的实验室研究结果，这些研究涉及药物暴露对眶额介导的学习任务以及眶额皮质中神经元结构和活动的影响。我们还讨论了关于眶额皮质在药物自我给药和复吸中作用的研究结果。我们的主要结论是，尽管有明确证据表明药物暴露会损害依赖眶额的学习任务并改变眶额皮质中的神经元活动，但这些变化在强迫性药物使用和复吸中所起的确切作用尚未确定。
