Neuromedical AI Lab, Department of Neurosurgery, Medical Center - University of Freiburg, Engelbergerstr.21, D-79106 Freiburg im Breisgau, Germany; Epilepsy Center, Department of Neurosurgery, Medical Center - University of Freiburg, Freiburg, Germany; Neurobiology and Biophysics, Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany; BrainLinks-BrainTools Cluster of Excellence, University of Freiburg, Freiburg, Germany.
Epilepsy Center, Department of Neurosurgery, Medical Center - University of Freiburg, Freiburg, Germany; BrainLinks-BrainTools Cluster of Excellence, University of Freiburg, Freiburg, Germany.
Neuroimage. 2021 Apr 15;230:117788. doi: 10.1016/j.neuroimage.2021.117788. Epub 2021 Jan 24.
Blinks and saccades, both ubiquitous in natural viewing conditions, cause rapid changes of visual inputs that are hardly consciously perceived. The neural dynamics in early visual areas of the human brain underlying this remarkable visual stability are still incompletely understood. We used electrocorticography (ECoG) from electrodes directly implanted on the human early visual areas V1, V2, V3d/v, V4d/v and the fusiform gyrus to investigate blink- and saccade-related neuronal suppression effects during non-experimental, free viewing conditions. We found a characteristic, biphasic, broadband gamma power decrease-increase pattern in all investigated visual areas. During saccades, a decrease in gamma power clearly preceded eye movement onset, at least in V1. This may indicate that cortical information processing is actively suppressed in human early visual areas before and during saccades, which then possibly mediates perceptual visual suppression. The following eye movement offset-related increase in gamma power may indicate the recovery of visual perception and the resumption of visual processing.
眨眼和扫视是自然视觉条件下普遍存在的现象，会导致视觉输入的快速变化，而这些变化几乎无法被意识察觉。人类大脑早期视觉区域中支持这种显著视觉稳定性的神经动力学机制仍不完全清楚。我们使用直接植入人类早期视觉区域 V1、V2、V3d/v、V4d/v 和梭状回的皮层电图（ECoG），在非实验、自由观察条件下，研究眨眼和扫视相关的神经元抑制效应。我们在所有研究的视觉区域中发现了一种特征性的、双相的、宽带伽马功率下降-增加模式。在扫视过程中，伽马功率的下降明显先于眼球运动的开始，至少在 V1 中是这样。这可能表明，在扫视之前和期间，人类早期视觉区域中的皮质信息处理被主动抑制，然后可能介导了知觉视觉抑制。随后的与眼动结束相关的伽马功率增加可能表明视觉感知的恢复和视觉处理的恢复。
