While current dual-steam neurocognitive models of language function have coalesced around the view that distinct neuroanatomical networks subserve semantic and phonological processing, respectively, the specific white matter components of these networks remain a matter of debate. To inform this debate, we investigated relationships between structural white matter connectivity and word production in a cross-sectional study of 42 participants with aphasia due to unilateral left hemisphere stroke. Specifically, we reconstructed a local connectome matrix for each participant from diffusion spectrum imaging data and regressed these matrices on indices of semantic and phonological ability derived from their responses to a picture-naming test and a computational model of word production. These connectometry analyses indicated that both dorsally located (arcuate fasciculus) and ventrally located (inferior frontal-occipital, uncinate, and middle longitudinal fasciculi) tracts were associated with semantic ability, while associations with phonological ability were more dorsally situated, including the arcuate and middle longitudinal fasciculi. Associations with limbic pathways including the posterior cingulum bundle and the fornix were also found. All analyses controlled for total lesion volume and all results showing positive associations obtained false discovery rates < 0.05. These results challenge dual-stream accounts that deny a role for the arcuate fasciculus in semantic processing, and for ventral-stream pathways in language production. They also illuminate limbic contributions to both semantic and phonological processing for word production.

中文翻译：

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失语症单词产生的结构性白质关联法：一项观察性研究。

尽管当前关于语言功能的双蒸汽神经认知模型已经融合在一起，即不同的神经解剖网络分别支持语义和语音处理，但这些网络中特定的白质成分仍存在争议。为了给这场辩论提供信息，我们在一项横断面研究中调查了结构性白质连通性与单词产生之间的关系，该研究涉及42位因单侧左半球卒中而失语的参与者。具体来说，我们从扩散光谱成像数据中为每个参与者重建了一个局部连接词组矩阵，并将这些矩阵回归到语义和语音能力指标上，这些指标源自他们对图片命名测试的响应以及单词产生的计算模型。这些连接法分析表明，背侧位置（弓形筋膜）和腹侧位置（额额枕下，未结和中纵筋膜下）束均与语义能力相关，而与语音能力的关联则更背侧分布，包括弓形和中间纵向筋膜。还发现与包括后扣带束和穹ni在内的边缘通路相关。所有分析均控制了总病变体积，所有显示出正关联的结果均获得了<0.05的错误发现率。这些结果挑战了双流帐户，这些帐户否认了弓形束在语义处理中的作用以及在腹腔流途径在语言生成中的作用。