Queensland Brain Institute, University of Queensland, Brisbane, Australia; Department of Experimental Psychology, University of Oxford, Oxford, UK.
Department of Experimental Psychology, University of Oxford, Oxford, UK.
Neuropsychologia. 2023 Jun 6;184:108502. doi: 10.1016/j.neuropsychologia.2023.108502. Epub 2023 Mar 9.
Word-centred neglect dyslexia is most commonly characterised as consequence of visuospatial neglect rather than an independent condition. However, recent research has suggested that this deficit may be dissociable from spatial attentional biases. This study aims to provide preliminary evidence investigating alternative mechanisms which could account for cases of word-centred neglect dyslexia which cannot be explained by visuospatial neglect. Patient EF is a chronic stroke survivor who presented with clear right-lateralised word-centred neglect dyslexia in conjunction with severe left egocentric neglect and left hemianopia following a right PCA stroke. The severity of EF's neglect dyslexia was not found to be affected by factors which modulate the severity of visuospatial neglect. EF demonstrated an intact ability to identify all letters in words, but reliably committed neglect dyslexia errors when subsequently reading the same words as a whole. EF did not exhibit neglect dyslexic impairment in standardised spelling, word-meaning matching, and word-picture matching tasks. Critically, EF exhibited marked cognitive inhibition impairment and committed neglect dyslexia errors which were characterised by misreading less familiar target words as more familiar responses. This behavioural pattern cannot be clearly accounted for by theories which characterize word-centred neglect dyslexia as a consequence of neglect. Instead, this data suggests that this case of word-centred neglect dyslexia may be related to a deficit of cognitive inhibition. Overall, these novel findings call for reevaluation of the dominant model of word-centred neglect dyslexia.
以词为中心的忽视性失读症通常被认为是视空间忽视的结果，而不是一种独立的病症。然而，最近的研究表明，这种缺陷可能与空间注意偏向分离。本研究旨在提供初步证据，探讨可以解释无法用视空间忽视来解释的以词为中心的忽视性失读症的替代机制。
患者 EF 是一名慢性中风幸存者，在右大脑后动脉中风后表现出明显的右侧以词为中心的忽视性失读症，同时伴有严重的左侧自我中心忽视和左侧偏盲。EF 的忽视性失读症的严重程度并未发现受到调节视空间忽视严重程度的因素的影响。EF 表现出识别单词中所有字母的能力完好，但在随后将相同的单词作为一个整体阅读时，却可靠地出现了忽视性失读错误。EF 在标准化拼写、单词意义匹配和单词-图片匹配任务中没有表现出忽视性失读障碍。
至关重要的是，EF 表现出明显的认知抑制障碍，并出现了忽视性失读错误，这些错误的特征是将不太熟悉的目标单词误读为更熟悉的反应。这种行为模式不能用将以词为中心的忽视性失读症描述为忽视结果的理论清楚地解释。相反，这些数据表明，这种以词为中心的忽视性失读症可能与认知抑制缺陷有关。
总的来说，这些新发现呼吁重新评估以词为中心的忽视性失读症的主导模型。
