Hampton William H, Alm Kylie H, Venkatraman Vinod, Nugiel Tehila, Olson Ingrid R
Department of Psychology, College of Liberal Arts, Temple University, USA; Decision Neuroscience, College of Liberal Arts, Temple University, USA.
Department of Psychology, College of Liberal Arts, Temple University, USA.
Neuroimage. 2017 Apr 15;150:336-343. doi: 10.1016/j.neuroimage.2017.02.021. Epub 2017 Feb 9.
Dysfunction of cognitive control often leads to impulsive decision-making in clinical and healthy populations. Some research suggests that a generalized cognitive control mechanism underlies the ability to modulate various types of impulsive behavior, while other evidence suggests different forms of impulsivity are dissociable, and rely on distinct neural circuitry. Past research consistently implicates several brain regions, such as the striatum and portions of the prefrontal cortex, in impulsive behavior. However the ventral and dorsal striatum are distinct in regards to function and connectivity. Nascent evidence points to the importance of frontostriatal white matter connectivity in impulsivity, yet it remains unclear whether particular tracts relate to different control behaviors. Here we used probabilistic tractography of diffusion imaging data to relate ventral and dorsal frontostriatal connectivity to reward and motor impulsivity measures. We found a double dissociation such that individual differences in white matter connectivity between the ventral striatum and the ventromedial prefrontal cortex and dorsolateral prefrontal cortex was associated with reward impulsivity, as measured by delay discounting, whereas connectivity between dorsal striatum and supplementary motor area was associated with motor impulsivity, but not vice versa. Our findings suggest that (a) structural connectivity can is associated with a large amount of behavioral variation; (b) different types of impulsivity are driven by dissociable frontostriatal neural circuitry.
认知控制功能障碍在临床人群和健康人群中常常导致冲动决策。一些研究表明，一种广义的认知控制机制是调节各类冲动行为能力的基础，而其他证据则表明不同形式的冲动性是可分离的，且依赖于不同的神经回路。过去的研究一直表明，包括纹状体和部分前额叶皮质在内的几个脑区与冲动行为有关。然而，腹侧纹状体和背侧纹状体在功能和连接性方面有所不同。新出现的证据表明额纹状体白质连接在冲动性方面具有重要性，但尚不清楚特定的神经束是否与不同的控制行为相关。在这里，我们使用扩散成像数据的概率性纤维束成像来将腹侧和背侧额纹状体连接与奖励冲动性和运动冲动性测量联系起来。我们发现了一种双重分离现象，即腹侧纹状体与腹内侧前额叶皮质和背外侧前额叶皮质之间的白质连接的个体差异与通过延迟折扣测量的奖励冲动性相关，而背侧纹状体与辅助运动区之间的连接与运动冲动性相关，但反之不然。我们的研究结果表明：（a）结构连接性与大量行为变异相关；（b）不同类型的冲动性由可分离的额纹状体神经回路驱动。
