Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA.
Schizophr Bull. 2019 Mar 7;45(2):386-395. doi: 10.1093/schbul/sby028.
Schizophrenia has been characterized as a neurodevelopmental disorder, with structural brain abnormalities reported at all stages. However, at present, it remains unclear whether gray and white matter abnormalities represent related or independent pathologies in schizophrenia. In this study, we present findings from an integrative analysis exploring the morphological relationship between gray and white matter in 45 schizophrenia participants and 49 healthy controls. We utilized mutual information (MI), a measure of how much information two variables share, to assess the morphological dependence between gray and white matter in three segments of the corpus callsoum, and the gray matter regions these segments connect: (1) the genu and the left and right rostral middle frontal gyrus (rMFG), (2) the isthmus and the left and right superior temporal gyrus (STG), (3) the splenium and the left and right lateral occipital gyrus (LOG). We report significantly reduced MI between white matter tract dispersion of the right hemispheric callosal connections to the STG and both cortical thickness and area in the right STG in schizophrenia patients, despite a lack of group differences in cortical thickness, surface area, or dispersion. We believe that this reduction in morphological dependence between gray and white matter may reflect a possible decoupling of the developmental processes that shape morphological features of white and gray matter early in life. The present study also demonstrates the importance of studying the relationship between gray and white matter measures, as opposed to restricting analyses to gray and white matter measures independently.
精神分裂症一直被认为是一种神经发育障碍，在各个阶段都有报道称存在大脑结构异常。然而，目前仍不清楚灰质和白质异常是否代表精神分裂症中的相关或独立病理。在这项研究中，我们呈现了一项综合分析的结果，该分析探讨了 45 名精神分裂症患者和 49 名健康对照者的灰质和白质之间的形态关系。我们利用互信息（MI），即两个变量共享多少信息的度量标准，来评估胼胝体三个节段以及这些节段连接的灰质区域之间的灰质和白质之间的形态依赖关系：（1）膝部和左右额中回的前部（rMFG），（2）峡部和左右颞上回（STG），（3）压部和左右外侧枕叶回（LOG）。我们报告称，精神分裂症患者右侧半球胼胝体连接到 STG 的白质束弥散的 MI 显著降低，尽管 STG 皮质厚度和面积在两组之间没有差异。我们认为，灰质和白质之间形态依赖性的降低可能反映了塑造白质和灰质形态特征的发育过程的可能分离。本研究还表明，研究灰质和白质测量之间的关系非常重要，而不是将分析仅限于单独的灰质和白质测量。
