Center for Interdisciplinary Brain Sciences Research, Stanford University School of Medicine, Palo Alto, CA 94305, USA.
Cereb Cortex. 2011 Nov;21(11):2471-81. doi: 10.1093/cercor/bhr017. Epub 2011 Mar 25.
Turner syndrome (TS) is a genetic disorder affecting females, resulting from the complete or partial absence of an X chromosome. The cognitive profile of TS shows relative strengths in the verbal domain and weaknesses in the procedural domain, including working memory. Neuroimaging studies have identified differences in the morphology of the parietal lobes, and white matter pathways linking frontal and parietal regions, as well as abnormal activation in dorsal frontal and parietal regions. Taken together these findings suggest that abnormal functional connectivity between frontal and parietal regions may be related to working memory impairments in TS, a hypothesis we tested in the present study. We scanned TS and typically developing participants with functional magnetic resonance imaging while they performed visuospatial and phonological working memory tasks. We generated a seed region in parietal cortex based on structural differences in TS and found that functional connectivity with dorsal frontal regions was reduced during working memory in TS. Finally, we found that connectivity was correlated with task performance in TS. These findings suggest that structural brain abnormalities in TS affect not only regional activity but also the functional interactions between regions and that this has important consequences for behavior.
特纳综合征（TS）是一种影响女性的遗传疾病，源于 X 染色体的完全或部分缺失。TS 的认知特征表现为言语领域的相对优势和程序性领域的劣势，包括工作记忆。神经影像学研究已经确定了顶叶区域形态学、连接额叶和顶叶区域的白质通路以及背侧额叶和顶叶区域的异常激活方面的差异。这些发现表明，额叶和顶叶区域之间异常的功能连接可能与 TS 中的工作记忆障碍有关，我们在本研究中检验了这一假设。我们对 TS 和发育正常的参与者进行了功能磁共振成像扫描，让他们执行视觉空间和语音工作记忆任务。我们根据 TS 中的结构差异在顶叶皮层中生成了一个种子区域，并发现在 TS 进行工作记忆时，与背侧额叶区域的功能连接减少。最后，我们发现连接与 TS 中的任务表现相关。这些发现表明，TS 中的结构性脑异常不仅影响区域活动，还影响区域之间的功能相互作用，这对行为有重要影响。
