Lavidor Michal, Alexander Tim, McGraw Paul V
Department of Psychology, University of Hull, Hull HU6 7RX, UK.
Perception. 2009;38(10):1536-41. doi: 10.1068/p6078.
Many visual tasks display a well-documented naso-temporal asymmetry (NTA), where sensitivity is greater to stimuli presented in the temporal hemifield. Four-letter strings were presented at various eccentricities under monocular vision conditions, and observers were asked to classify the stimuli as 'words' or 'non-words' in a lexical decision task (experiment 1). In experiment 2, the same observers had to classify the stimuli as 'darker' or 'lighter' (contrast discrimination). Apart from the task, the visual conditions and stimuli were identical in both experiments. The typical temporal hemifield advantage was found for a contrast discrimination task in both English and Hebrew readers, but only for lexical decision judgments in Hebrew readers. The lack of the expected NTA in English readers that was observed only for a reading but not a low-level visual task indicates that language lateralisation and reading-related learning can override fundamental, anatomically based, visual asymmetries.
许多视觉任务都呈现出一种有充分文献记载的鼻颞侧不对称（NTA），即对颞侧半视野中呈现的刺激的敏感性更高。在单眼视觉条件下，在不同偏心度处呈现四个字母的字符串，并要求观察者在词汇判断任务中（实验1）将刺激分类为“单词”或“非单词”。在实验2中，相同的观察者必须将刺激分类为“较暗”或“较亮”（对比度辨别）。除了任务不同外，两个实验中的视觉条件和刺激都是相同的。在英语和希伯来语读者中，对比度辨别任务均发现了典型的颞侧半视野优势，但仅在希伯来语读者的词汇判断中发现了这种优势。仅在阅读任务而非低水平视觉任务中观察到的英语读者中缺乏预期的鼻颞侧不对称现象，表明语言侧化和与阅读相关的学习可以超越基于解剖结构的基本视觉不对称。
