Centre for Brain and Mind, Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada.
Nat Neurosci. 2010 Nov;13(11):1421-7. doi: 10.1038/nn.2653. Epub 2010 Oct 10.
When the brain is deprived of input from one sensory modality, it often compensates with supranormal performance in one or more of the intact sensory systems. In the absence of acoustic input, it has been proposed that cross-modal reorganization of deaf auditory cortex may provide the neural substrate mediating compensatory visual function. We tested this hypothesis using a battery of visual psychophysical tasks and found that congenitally deaf cats, compared with hearing cats, have superior localization in the peripheral field and lower visual movement detection thresholds. In the deaf cats, reversible deactivation of posterior auditory cortex selectively eliminated superior visual localization abilities, whereas deactivation of the dorsal auditory cortex eliminated superior visual motion detection. Our results indicate that enhanced visual performance in the deaf is caused by cross-modal reorganization of deaf auditory cortex and it is possible to localize individual visual functions in discrete portions of reorganized auditory cortex.
当大脑被剥夺一种感觉模式的输入时，它通常会在一个或多个完整的感觉系统中表现出超常的补偿能力。在没有声学输入的情况下，有人提出，聋人听觉皮层的跨模态重组可能为介导代偿性视觉功能提供神经基础。我们使用一系列视觉心理物理任务来检验这一假设，结果发现，与听力猫相比，先天性聋猫在外周视野中的定位能力更强，视觉运动检测阈值更低。在聋猫中，后听觉皮层的可逆失活选择性地消除了优越的视觉定位能力，而背侧听觉皮层的失活则消除了优越的视觉运动检测。我们的结果表明，聋人视觉表现的增强是由聋人听觉皮层的跨模态重组引起的，并且有可能将个体的视觉功能定位到重组听觉皮层的离散部分。
