ADAPT-lab, Department of Psychology, University of Amsterdam, The Netherlands.
Neuroimage. 2012 Feb 15;59(4):3845-51. doi: 10.1016/j.neuroimage.2011.09.046. Epub 2011 Sep 29.
Cannabis abuse is related to impairments in a broad range of cognitive functions. However, studies on cannabis abuse in relation to brain structure are sparse and results are inconsistent, probably due to differences in imaging methodology, severity of cannabis abuse, and use of other substances. The goal of the current MRI study was to investigate brain morphology related to current and lifetime severity of cannabis use and dependence in heavy cannabis users without intensive use of other illicit drugs. Voxel-based morphometry was used to assess differences in regional grey and white matter volume between 33 heavy cannabis users and 42 matched controls. Within heavy cannabis users, grey and white matter volume was correlated with measures of cannabis use and dependence. Analyses were focused a priori on the orbitofrontal cortex, anterior cingulate cortex, striatum, amygdala, hippocampus, and cerebellum, regions implicated in substance dependence and/or with high cannabinoid receptor-1 concentrations. Regional grey matter volume in the anterior cerebellum was larger in heavy cannabis users. Within the group of heavy cannabis users, grey matter volume in the amygdala and hippocampus correlated negatively with the amount of cannabis use or dependence. No associations were found between white matter volume and measures of cannabis use or dependence. These findings indicate that associations between heavy cannabis use and altered brain structure are complex. Differential patterns of structural changes for various cannabis use levels imply that alterations in brain structure are associated with specific characteristics of cannabis use and dependence.
大麻滥用与广泛的认知功能障碍有关。然而，关于大麻滥用与大脑结构的研究很少，结果也不一致，这可能是由于成像方法、大麻滥用的严重程度以及其他物质的使用存在差异。本项 MRI 研究的目的是调查当前和终生大麻使用严重程度与依赖与重度大麻使用者的大脑形态学之间的关系，这些重度大麻使用者没有密集使用其他非法药物。体素形态计量学用于评估 33 名重度大麻使用者和 42 名匹配对照者之间的灰质和白质体积的差异。在重度大麻使用者中，灰质和白质体积与大麻使用和依赖的测量值相关。分析主要集中在眶额叶皮层、前扣带皮层、纹状体、杏仁核、海马和小脑，这些区域与物质依赖和/或高大麻素受体-1浓度有关。重度大麻使用者的前小脑灰质体积较大。在重度大麻使用者组中，杏仁核和海马的灰质体积与大麻使用量或依赖呈负相关。未发现白质体积与大麻使用或依赖的测量值之间存在相关性。这些发现表明，重度大麻使用与大脑结构改变之间的关联是复杂的。不同大麻使用水平的结构变化模式表明，大脑结构的改变与大麻使用和依赖的特定特征有关。
