Visual processing of multiple elements in the dyslexic brain: evidence for a superior parietal dysfunction.
Visual processing of multiple elements in the dyslexic brain: evidence for a superior parietal dysfunction.
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DOI：
10.3389/fnhum.2014.00479
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发表时间：
2014
影响因子：
2.9
通讯作者：
Valdois S
中科院分区：
文献类型：
--
作者：
Lobier MA;Peyrin C;Pichat C;Le Bas JF;Valdois S
发育性阅读障碍的视觉注意力（VA）跨度缺陷假说认为，多元素处理受损可能导致阅读结果不佳。在 VA 跨度受损的诵读困难儿童中，字母报告任务的表现不佳与多个字母处理的顶叶激活减少有关。虽然这暗示了一种非特异性的、基于注意力的功能障碍，但目前尚不清楚顶叶活动减少是否会普遍影响其他类型的刺激。此外，阅读障碍中顶叶活动减少和腹侧枕颞叶（vOT）减少之间的假定联系还有待探索。使用功能性磁共振成像，我们测量了 12 名 VA 跨度受损的阅读障碍成年人和 12 名成年熟练读者在对单个或多个字母数字或非字母数字字符执行分类任务时的大脑活动。虽然健康读者在多个元素处理时比单元素处理更强烈地激活顶叶区域（右侧用于字母数字，双边用于非字母数字），但阅读障碍参与者缺乏类似更强的多个元素右顶叶激活。熟练阅读者和阅读困难读者之间的对比显示，无论刺激类型如何，阅读困难阅读者的右上顶小叶（SPL）活动均显着降低。使用先验的解剖学定义的感兴趣区域，我们发现阅读障碍参与者在双边 SPL 和 vOT 中的神经活动均减少。最后，我们使用多元回归来测试每组中 SPL 活动是否与 vOT 活动相关。在左半球，正常读者和阅读困难读者的 SPL 活动与 vOT 活动呈协变关系。相比之下，在右半球，只有阅读困难的读者的 SPL 活动与 vOT 活动呈协变。这些结果为 VA 对 VA Span 赤字的解释提供了关键支持。此外，他们还提供了关于基于 vOT 的自动单词识别缺陷如何在发展性阅读障碍中出现的新见解。
The visual attention (VA) span deficit hypothesis of developmental dyslexia posits that impaired multiple element processing can be responsible for poor reading outcomes. In VA span impaired dyslexic children, poor performance on letter report tasks is associated with reduced parietal activations for multiple letter processing. While this hints towards a non-specific, attention-based dysfunction, it is still unclear whether reduced parietal activity generalizes to other types of stimuli. Furthermore, putative links between reduced parietal activity and reduced ventral occipito-temporal (vOT) in dyslexia have yet to be explored. Using functional magnetic resonance imaging, we measured brain activity in 12 VA span impaired dyslexic adults and 12 adult skilled readers while they carried out a categorization task on single or multiple alphanumeric or non-alphanumeric characters. While healthy readers activated parietal areas more strongly for multiple than single element processing (right-sided for alphanumeric and bilateral for non-alphanumeric), similar stronger multiple element right parietal activations were absent for dyslexic participants. Contrasts between skilled and dyslexic readers revealed significantly reduced right superior parietal lobule (SPL) activity for dyslexic readers regardless of stimuli type. Using a priori anatomically defined regions of interest, we showed that neural activity was reduced for dyslexic participants in both SPL and vOT bilaterally. Finally, we used multiple regressions to test whether SPL activity was related to vOT activity in each group. In the left hemisphere, SPL activity covaried with vOT activity for both normal and dyslexic readers. In contrast, in the right hemisphere, SPL activity covaried with vOT activity only for dyslexic readers. These results bring critical support to the VA interpretation of the VA Span deficit. In addition, they offer a new insight on how deficits in automatic vOT based word recognition could arise in developmental dyslexia.
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影响因子：
5.7
作者：
Friston, KJ;Zarahn, E;Dale, AM
通讯作者：
Dale, AM
影响因子：
5.7
作者：
Hahn, Britta;Ross, Thomas J.;Stein, Elliot A.
通讯作者：
Stein, Elliot A.
影响因子：
--
作者：
Bullier, J
通讯作者：
Bullier, J
DOI：
10.1073/pnas.0904402107
发表时间：
2010-04-27
影响因子：
11.1
作者：
Brem, Silvia;Bach, Silvia;Richardson, Ulla
通讯作者：
Richardson, Ulla
影响因子：
5.7
作者：
Brem, S;Bucher, K;Brandeis, D
通讯作者：
Brandeis, D