Departments of Neurology and Neuroophthalmology, University of British Columbia, 2550 Willow Street, Vancouver, British Columbia, Canada V5Z 3N9.
Neuropsychiatr Dis Treat. 2008 Dec;4(6):1129-53. doi: 10.2147/ndt.s4329.
Recent studies have suggested that some variants of bipolar disorder (BD) may be due to hyperconnectivity between orbitofrontal (OFC) and temporal pole (TP) structures in the dominant hemisphere. Some initial MRI studies noticed that there were corpus callosum abnormalities within specific regional areas and it was hypothesized that developmentally this could result in functional or effective connectivity changes within the orbitofrontal-basal ganglia-thalamocortical circuits. Recent diffusion tensor imaging (DTI) white matter fiber tractography studies may well be superior to region of interest (ROI) DTI in understanding BD. A "ventral semantic stream" has been discovered connecting the TP and OFC through the uncinate and inferior longitudinal fasciculi and the elusive TP is known to be involved in theory of mind and complex narrative understanding tasks. The OFC is involved in abstract valuation in goal and sub-goal structures and the TP may be critical in binding semantic memory with person-emotion linkages associated with narrative. BD patients have relative attenuation of performance on visuoconstructional praxis consistent with an atypical localization of cognitive functions. Multiple lines of evidence suggest that some BD alleles are being selected for which could explain the enhanced creativity in higher-ability probands. Associations between ROI's that are not normally connected could explain the higher incidence of artistic aptitude, writing ability, and scientific achievements among some mood disorder subjects.
最近的研究表明，一些双相情感障碍 (BD) 的变体可能是由于优势半球的眶额 (OFC) 和颞极 (TP) 结构之间的超连接。一些初始的 MRI 研究注意到在特定的区域内有胼胝体异常，并且有人假设这可能导致眶额-基底神经节-丘脑皮质回路中的功能或有效连接变化。最近的弥散张量成像 (DTI) 白质纤维束追踪研究可能优于感兴趣区域 (ROI) DTI，有助于理解 BD。已经发现了一条“腹侧语义流”，通过钩束和下纵束将 TP 和 OFC 连接起来，并且难以捉摸的 TP 已知与心理理论和复杂叙事理解任务有关。OFC 参与目标和子目标结构中的抽象估值，而 TP 可能在将语义记忆与与叙事相关的人与情感联系绑定方面至关重要。BD 患者在视觉建构性实践方面的表现相对减弱，与认知功能的非典型定位一致。多条证据表明，一些 BD 等位基因正在被选择，这可以解释高能力先证者的创造力增强。通常不连接的 ROI 之间的关联可以解释一些心境障碍受试者中艺术天赋、写作能力和科学成就的更高发生率。
