Brang David, Towle Vernon L, Suzuki Satoru, Hillyard Steven A, Di Tusa Senneca, Dai Zhongtian, Tao James, Wu Shasha, Grabowecky Marcia
Department of Psychology, Northwestern University, Evanston, Illinois; Interdepartmental Neuroscience Program, Northwestern University, Evanston, Illinois; Department of Neurology, University of Chicago, Chicago, Illinois; and
Department of Neurology, University of Chicago, Chicago, Illinois; and.
J Neurophysiol. 2015 Nov;114(5):3023-8. doi: 10.1152/jn.00728.2015. Epub 2015 Sep 2.
Neurophysiological studies with animals suggest that sounds modulate activity in primary visual cortex in the presence of concurrent visual stimulation. Noninvasive neuroimaging studies in humans have similarly shown that sounds modulate activity in visual areas even in the absence of visual stimuli or visual task demands. However, the spatial and temporal limitations of these noninvasive methods prevent the determination of how rapidly sounds activate early visual cortex and what information about the sounds is relayed there. Using spatially and temporally precise measures of local synaptic activity acquired from depth electrodes in humans, we demonstrate that peripherally presented sounds evoke activity in the anterior portion of the contralateral, but not ipsilateral, calcarine sulcus within 28 ms of sound onset. These results suggest that auditory stimuli rapidly evoke spatially specific activity in visual cortex even in the absence of concurrent visual stimulation or visual task demands. This rapid auditory-evoked activation of primary visual cortex is likely to be mediated by subcortical pathways or direct cortical projections from auditory to visual areas.
对动物的神经生理学研究表明，在同时存在视觉刺激的情况下，声音会调节初级视觉皮层的活动。对人类进行的非侵入性神经成像研究同样表明，即使在没有视觉刺激或视觉任务要求的情况下，声音也会调节视觉区域的活动。然而，这些非侵入性方法在空间和时间上的局限性使得我们无法确定声音激活早期视觉皮层的速度有多快，以及关于声音的哪些信息会在那里传递。通过使用从人类深度电极获取的对局部突触活动在空间和时间上的精确测量，我们证明，在声音开始后的28毫秒内，外周呈现的声音会在对侧而不是同侧距状沟的前部诱发活动。这些结果表明，即使在没有同时存在的视觉刺激或视觉任务要求的情况下，听觉刺激也会在视觉皮层中迅速诱发空间特异性活动。初级视觉皮层这种快速的听觉诱发激活可能是由皮层下通路或从听觉区域到视觉区域的直接皮层投射介导的。
