School of Cognitive Sciences, Institute for Research in Fundamental Sciences (IPM), Tehran, 193955746, Iran.
Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, UT, 84132, USA.
Nat Commun. 2018 Dec 19;9(1):5393. doi: 10.1038/s41467-018-07816-4.
Correlations between neurons can profoundly impact the information encoding capacity of a neural population. We studied how maintenance of visuospatial information affects correlated activity in visual areas by recording the activity of neurons in visual area MT of rhesus macaques during a spatial working memory task. Correlations between MT neurons depended upon the spatial overlap between neurons' receptive fields. These correlations were influenced by the content of working memory, but the effect of a top-down memory signal differed in the presence or absence of bottom-up visual input. Neurons representing the same area of space showed increased correlations when remembering a location in their receptive fields in the absence of visual input, but decreased correlations in the presence of a visual stimulus. This set of results reveals the correlating nature of top-down signals influencing visual areas and uncovers how such a correlating signal, in interaction with bottom-up information, could enhance sensory representations.
神经元之间的相关性可以深刻影响神经元群体的信息编码能力。我们通过在恒河猴的视觉区域 MT 中记录神经元的活动，研究了在空间工作记忆任务中，视觉空间信息的保持如何影响视觉区域中的相关活动。MT 神经元之间的相关性取决于神经元感受野之间的空间重叠。这些相关性受到工作记忆内容的影响，但自上而下的记忆信号的影响在有无视觉输入的情况下有所不同。当在没有视觉输入的情况下记住其感受野中的位置时，代表相同空间区域的神经元显示出相关性增加，但在存在视觉刺激的情况下，相关性降低。这组结果揭示了影响视觉区域的自上而下信号的相关性质，并揭示了这种相关信号如何与自下而上的信息相互作用，从而增强感官表达。
