Can oscillation entrainment and attention improve visual perception?

神经元活动的周期性波动，即振荡，在视觉感知中具有功能性作用， 通过内隐注意（我们在视觉场景中的一个位置选择性地处理信息的能力）来改善 没有眼睛运动）。振荡性脑活动与视觉空间注意力的参与相关， 影响健康观察者的表现。在神经系统患者中， 脑损伤伴随着视觉障碍。然而，没有任何研究系统地操纵或核心- 视觉振荡活动，或其与内隐注意的相互作用，以改善健康成人的视觉表现， 使用经颅磁刺激（TMS）;一种成熟的、局灶性和非侵入性脑刺激 法这种知识对于改善健康人类观察者的感知功能和康复是重要的。 使患者产生错误的感知。对于健康的观察者，我们将使用TMS节奏模式来引导局部 振荡活动在特定的皮质网站单独和/或结合注意。我们将评估是否 振荡活动的夹带（即，相位对准和增加的功率）有助于对比敏感性。 ty-一个基本的、众所周知的视觉维度，决定了可见度的窗口，通过以下方式增加 关注在目标1中，我们将测试振荡定制的节奏TMS改善视觉表现的能力， 并记录其时频特征。我们将应用短暂的有节奏的主动TMS或有节奏的假TMS（非 磁安慰剂）刺激在α-10 Hz和β-30 Hz频率，在刺激开始到两个皮质 参与感知和注意力调节的区域：右枕叶（V1）和额叶（FEF）部位。我们 通过操纵显示和TMS突发发作之间的间隔来探索相位的影响。当操纵- 在后期阶段，我们将比较（a）节律性活动与随机活动TMS（相同脉冲数）的影响 和持续时间）;（B）节律性假刺激与随机假刺激;（c）节律性主动TMS与节律性假刺激。 （d）随机主动TMS与随机假刺激，阈值和渐近性能， 评估对比度增益和/或响应增益的变化。在目标2中，我们将专注于最有效的核心- 目标1中发现的位置-频率-相位模式组合，通过效应的大小和连续性进行评估， 在观察者之间进行simulation，以测试内隐注意是否可以增强这种效果。我们将操纵前- 外生（无意识的，反射性的）注意，这不是认知上的要求，并已被很好地表征 心理物理学神经成像和电生理学通过同时进行TMS-EEG记录 当观察者执行辨别任务时，我们将增加对大脑如何处理的理解。 视觉信息，神经活动的夹带如何与感知改善相关，以及如何覆盖- ert注意力影响视觉处理的空间和时间方面。此外，这项建议将探讨 无创性神经刺激结合注意力操作诱导脑振荡的可行性 活动和改善健康观察者的视觉功能，并在未来恢复患者的视力。

Periodic fluctuations of neuronal activity, i.e. oscillations, have a functional role in visual perception, which is improved by covert attention (our ability to selectively process information at one location in the visual scene without eye movements). Oscillatory brain activity correlates with the engagement of visuospatial attention and influences performance in healthy observers. In neurological patients, abnormal oscillatory activity following brain damage accompanies visual impairments. However, no study has systematically manipulated either cor- tical oscillatory activity, or its interaction with covert attention, to improve visual performance in healthy adults, using Transcranial Magnetic Stimulation (TMS); a well-established, focal and non-invasive brain stimulation technique. This knowledge is important to improve perceptual function in healthy human observers and rehabil- itate faulty perception in patients. With healthy observers, we will use TMS rhythmic patterns to entrain local oscillatory activity in specific cortical sites alone and/or in combination with attention. We will assess whether the entrainment of oscillatory activity (i.e., phase alignment and increased power) facilitates contrast sensitivi- ty–a fundamental, well-understood visual dimension determining the window of visibility, which is increased by attention. In Aim 1, we will test the ability of oscillation-tailored rhythmic TMS to improve visual performance, and record its time-frequency signature. We will apply either brief rhythmic active TMS or rhythmic sham (non- magnetic placebo) stimulation at the Alpha–10Hz and Beta–30Hz frequencies, at stimulus onset to two cortical areas involved in the modulation of perception and attention: right occipital (V1) and frontal (FEF) sites. We explore the effect of phase by manipulating the interval between display and TMS burst onsets. While manipu- lating phase, we will compare the impact of (a) rhythmic active vs. random active TMS (same pulse number and duration); (b) rhythmic sham vs. random sham stimulation; (c) rhythmic active TMS vs. rhythmic sham sti- mulation; (d) random active TMS vs. random sham stimulation, on threshold and asymptotic performance to assess changes in contrast gain and/or response gain. In Aim 2, we will concentrate on the most effective cor- tical site-frequency-phase pattern combination found in Aim 1, as assessed by the size of the effects and con- sistency across observers, to test whether covert attention can potentiate such effects. We will manipulate ex- ogenous (involuntary, reflexive) attention, which is not cognitively demanding and has been well-characterized with psychophysics, neuroimaging and electrophysiology. By conducting concurrent TMS-EEG recordings while observers perform a discrimination task, we will increase our understanding of how the brain processes visual information, how the entrainment of neural activity is related to perceptual improvements, and how cov- ert attention affects spatial and temporal aspects of visual processing. In addition, this proposal will probe the feasibility of non-invasive neurostimulation combined with attentional manipulations to entrain brain oscillatory activity and improve visual function in healthy observers, and, in the future, restore vision in patients.