Cognitive Neuroimaging Unit, CEA DSV/I2BM, INSERM, Université Paris-Sud, Université Paris-Saclay, NeuroSpin Center, Gif/Yvette 91191, France.
Department of Vision &Cognition, Netherlands Institute for Neurosciences, Meibergdreef 47, Amsterdam 1105 BA, The Netherlands.
Nat Commun. 2017 Jan 5;8:13804. doi: 10.1038/ncomms13804.
Neuronal activity in early visual cortex depends on attention shifts but the contribution to working memory has remained unclear. Here, we examine neuronal activity in the different layers of the primary visual cortex (V1) in an attention-demanding and a working memory task. A current-source density analysis reveales top-down inputs in the superficial layers and layer 5, and an increase in neuronal firing rates most pronounced in the superficial and deep layers and weaker in input layer 4. This increased activity is strongest in the attention task but it is also highly reliable during working memory delays. A visual mask erases the V1 memory activity, but it reappeares at a later point in time. These results provide new insights in the laminar circuits involved in the top-down modulation of activity in early visual cortex in the presence and absence of visual stimuli.
早期视觉皮层的神经元活动依赖于注意转移,但它对工作记忆的贡献仍不清楚。在这里,我们在一个注意力任务和一个工作记忆任务中检查初级视觉皮层(V1)的不同层的神经元活动。电流密度分析显示,自上而下的输入存在于浅层和第 5 层,神经元放电率的增加在浅层和深层最为明显,在输入层 4 较弱。这种活动的增加在注意任务中最为强烈,但在工作记忆延迟期间也非常可靠。视觉掩蔽会抹去 V1 的记忆活动,但稍后它会重新出现。这些结果为在存在和不存在视觉刺激的情况下,早期视觉皮层活动的自上而下调制所涉及的分层电路提供了新的见解。