Martin Randi C, Ding Junhua, Hamilton A Cris, Schnur Tatiana T
Department of Psychological Sciences, Rice University, Houston, TX 77251, USA.
Department of Neurosurgery, Baylor College of Medicine, Houston, TX 77030, USA.
Cereb Cortex Commun. 2021 Jan 28;2(2):tgab005. doi: 10.1093/texcom/tgab005. eCollection 2021.
Substantial behavioral evidence implies the existence of separable working memory (WM) components for maintaining phonological and semantic information. In contrast, only a few studies have addressed the neural basis of phonological versus semantic WM using functional neuroimaging and none has used a lesion-symptom mapping (LSM) approach. Here, we address this gap, reporting a multivariate LSM study of phonological and semantic WM for 94 individuals at the acute stage of left hemisphere stroke. Testing at the acute stage avoids issues of brain reorganization and the adoption of patient strategies for task performance. The LSM analyses for each WM component controlled for the other WM component and semantic and phonological knowledge at the single word level. For phonological WM, the regions uncovered included the supramarginal gyrus, argued to be the site of phonological storage, and several cortical and subcortical regions plausibly related to inner rehearsal. For semantic WM, inferior frontal regions and the angular gyrus were uncovered. The findings thus provide converging evidence for separable systems for phonological and semantic WM that are distinguished from the systems supporting long-term knowledge representations in those domains.
大量行为学证据表明，存在用于维持语音和语义信息的可分离工作记忆（WM）成分。相比之下，只有少数研究使用功能神经影像学探讨了语音与语义工作记忆的神经基础，且尚无研究采用损伤-症状映射（LSM）方法。在此，我们填补这一空白，报告一项针对94名左半球中风急性期患者的语音和语义工作记忆的多变量LSM研究。在急性期进行测试可避免脑重组问题以及患者采用任务执行策略的问题。每个工作记忆成分的LSM分析在单字水平上控制了另一个工作记忆成分以及语义和语音知识。对于语音工作记忆，发现的区域包括缘上回（被认为是语音存储部位）以及几个可能与内部复述相关的皮质和皮质下区域。对于语义工作记忆，发现了额下回区域和角回。因此，这些发现为语音和语义工作记忆的可分离系统提供了趋同证据，这些系统与支持这些领域长期知识表征的系统不同。
