Connally Emily L, Ward David, Howell Peter, Watkins Kate E
Department of Experimental Psychology & Oxford Centre for Functional MRI of the Brain (FMRIB), University of Oxford, South Parks Road, Oxford OX1 3UD, UK.
School of Psychology and Clinical Language Sciences, University of Reading, Earley Gate, Whiteknights Road, Reading RG6 6AL, UK.
Brain Lang. 2014 Apr;131:25-35. doi: 10.1016/j.bandl.2013.05.013. Epub 2013 Jun 29.
White matter tracts connecting areas involved in speech and motor control were examined using diffusion-tensor imaging in a sample of people who stutter (n=29) who were heterogeneous with respect to age, sex, handedness and stuttering severity. The goals were to replicate previous findings in developmental stuttering and to extend our knowledge by evaluating the relationship between white matter differences in people who stutter and factors such as age, sex, handedness and stuttering severity. We replicated previous findings that showed reduced integrity in white matter underlying ventral premotor cortex, cerebral peduncles and posterior corpus callosum in people who stutter relative to controls. Tractography analysis additionally revealed significantly reduced white matter integrity in the arcuate fasciculus bilaterally and the left corticospinal tract and significantly reduced connectivity within the left corticobulbar tract in people who stutter. Region-of-interest analyses revealed reduced white matter integrity in people who stutter in the three pairs of cerebellar peduncles that carry the afferent and efferent fibers of the cerebellum. Within the group of people who stutter, the higher the stuttering severity index, the lower the white matter integrity in the left angular gyrus, but the greater the white matter connectivity in the left corticobulbar tract. Also, in people who stutter, handedness and age predicted the integrity of the corticospinal tract and peduncles, respectively. Further studies are needed to determine which of these white matter differences relate to the neural basis of stuttering and which reflect experience-dependent plasticity.
我们使用扩散张量成像技术，对一组口吃者（n = 29）的连接言语和运动控制相关区域的白质束进行了检查，这些口吃者在年龄、性别、利手和口吃严重程度方面具有异质性。目的是重复发育性口吃的先前研究结果，并通过评估口吃者白质差异与年龄、性别、利手和口吃严重程度等因素之间的关系来扩展我们的认识。我们重复了先前的研究结果，即与对照组相比，口吃者腹侧运动前皮质、大脑脚和胼胝体后部下方的白质完整性降低。纤维束成像分析还显示，口吃者双侧弓状束、左侧皮质脊髓束的白质完整性显著降低，左侧皮质延髓束内的连接性显著降低。感兴趣区域分析显示，口吃者携带小脑传入和传出纤维的三对小脑脚的白质完整性降低。在口吃者组中，口吃严重程度指数越高，左侧角回的白质完整性越低，但左侧皮质延髓束的白质连接性越高。此外，在口吃者中，利手和年龄分别预测了皮质脊髓束和大脑脚的完整性。需要进一步的研究来确定这些白质差异中哪些与口吃的神经基础有关，哪些反映了经验依赖性可塑性。
