From correlation to causation: The functional role of ongoing neuronal oscillations for perception

神经元振荡是人类和其他物种大脑中普遍存在的现象。尽管它们无处不在，但它们在感知和其他认知功能中的作用仍然没有被完全理解。最近的研究表明，即使在刺激前几百毫秒发生的自发的、持续的神经元振荡也可以极大地影响对这些刺激的感知。此外，其中一些研究甚至表明，我们的感知可能是一个离散的过程，而不是持续不变的。也就是说，类似于摄像机，我们的感知可能是通过生成环境的离散快照来工作的。因此，连续感知的主观印象只不过是一种错觉。这些研究表明，特定频段的神经元振荡可能形成了这些感知快照的神经元基础。虽然这种关于感知的观点很耐人寻味，最近也获得了相当多的支持，但证据仍然很少。最重要的是，离散知觉的证据和神经元振荡对一般知觉和特别是离散知觉的功能作用的证据大多是相关的。也就是说，因果证据在很大程度上仍然缺失。在这个提议中，我们的目标是研究正在进行的神经元振荡和知觉之间的因果关系。我们将使用不同的方法，如Tacs来调节健康受试者正在进行的神经元振荡。同时，我们将测量这些调制对脑磁图的神经元处理和行为任务中的知觉的因果影响。这些项目将为进一步阐明和确定正在进行的神经元振荡对神经元处理、大脑状态、离散知觉和一般知觉的作用提供重要的一步。

Neuronal oscillations are a ubiquitous phenomenon in the brains of humans and other species. Despite their ubiquity, their role for perception and other cognitive functions is still not fully understood. Recent studies indicate that spontaneous, ongoing neuronal oscillations occurring even a few hundred milliseconds before a stimulus can substantially influence the perception of these stimuli. Moreover, some of these studies even have suggested that rather than being constant and continuous, our perception might be a discrete process. That is, similar to a video camera, our perception might work by producing discrete snapshots of our environment. The subjective impression of continuous perception is thus not more than an illusion. These studies suggest that neuronal oscillations at specific frequency bands might form the neuronal basis for these snapshots of perception. While this view on perception is intriguing and has gathered quite some support recently, evidence is still sparse. Most importantly, evidence for discrete perception and for a function role of neuronal oscillations for perception in general and discrete perception in particular has mostly been correlative. That is, causal evidence is still largely missing. In this proposal, we aim to study the causal relationship between ongoing neuronal oscillations and perception. We will use different methodological approaches such as tACS to modulate ongoing neuronal oscillations in healthy subjects. Simultaneously, we will measure the causal impact of these modulations on neuronal processing by MEG and on perception in behavioural tasks. These projects will provide an important step to further elucidate and establish the role of ongoing neuronal oscillations for neuronal processing, brain states, discrete perception and perception in general.