Institute for Human Neuroscience, Boys Town National Research Hospital, Omaha, Nebraska.
College of Medicine, Creighton University, Omaha, Nebraska.
J Neurophysiol. 2022 Apr 1;127(4):928-937. doi: 10.1152/jn.00380.2021. Epub 2022 Mar 9.
Visual processing is widely understood to be served by a decrease in alpha activity in occipital cortices, largely concurrent with an increase in gamma activity. Although the characteristics of these oscillations are well documented in response to a range of complex visual stimuli, little is known about how these dynamics are impacted by concurrent motor responses, which is problematic as many common visual tasks involve such responses. Thus, in the current study, we used magnetoencephalography (MEG) and modified a well-established visual paradigm to explore the impact of motor responses on visual oscillatory activity. Thirty-four healthy adults viewed a moving gabor (grating) stimulus that was known to elicit robust alpha and gamma oscillations in occipital cortices. Frequency and power characteristics were assessed statistically for differences as a function of movement condition. Our results indicated that occipital alpha significantly increased in power during movement relative to no movement trials. No differences in peak frequency or power were found for gamma responses between the two movement conditions. These results provide valuable evidence of visuomotor integration and underscore the importance of careful task design and interpretation, especially in the context of complex visual processing, and suggest that even basic motor responses alter occipital visual oscillations in healthy adults. Processing of visual stimuli is served by occipital alpha and gamma activity. Many studies have investigated the impact of visual stimuli on motor cortical responses, but few studies have systematically investigated the impact of motor responses on visual oscillations. We found that when participants are asked to move in response to a visual stimulus, occipital alpha power was modulated whereas gamma responses were unaffected. This suggests that these responses have dissociable roles in visuomotor integration.
视觉处理被广泛认为是通过枕叶皮质中 alpha 活动的减少和 gamma 活动的增加来实现的。虽然这些振荡的特征在对一系列复杂视觉刺激的反应中得到了很好的记录，但对于这些动力学如何受到并发运动反应的影响知之甚少，因为许多常见的视觉任务都涉及到这种反应。因此，在目前的研究中，我们使用脑磁图（MEG）并修改了一个成熟的视觉范式，来探索运动反应对视觉振荡活动的影响。34 名健康成年人观看了一个移动的伽马（光栅）刺激，该刺激已知会在枕叶皮质中引起强烈的 alpha 和 gamma 振荡。通过运动条件的函数评估了频率和功率特征的差异。我们的结果表明，与无运动试验相比，运动时枕叶 alpha 的功率显著增加。在两种运动条件下，gamma 反应的峰值频率或功率没有差异。这些结果提供了视觉运动整合的有价值的证据，并强调了在复杂视觉处理的背景下，精心设计和解释任务的重要性，尤其是在复杂视觉处理的背景下，这表明即使是基本的运动反应也会改变健康成年人的枕叶视觉振荡。视觉刺激的处理由枕叶 alpha 和 gamma 活动提供。许多研究调查了视觉刺激对运动皮质反应的影响，但很少有研究系统地研究了运动反应对视觉振荡的影响。我们发现，当要求参与者对视觉刺激做出反应时，枕叶 alpha 功率被调节，而 gamma 反应不受影响。这表明这些反应在视觉运动整合中具有可分离的作用。
