Electrical stimulation to control feedback modulation of perception

摘要 视觉感知是视觉输入和注意状态的融合。视觉输入是如何处理的以及 在人类视皮层中的代表正以越来越高的精度在现场被捕获。然而，一个关键的 我们在理解上的差距是来自更高阶区的自上而下的输入如何影响和塑造感觉 加工--尤其是建立在直接因果操作基础上的理解。中国的长期目标是 建议的研究是开发因果扰动方法，以如下方式调节视觉处理 模仿注意力的过程。为了实现这一目标，我们将使用电刺激来测试、提炼和扩展 反馈信息流到腹侧颞叶皮质(VTC)的定量模型。我们的研究 利用癫痫手术中最近的一项临床转变，从脑表面脑电记录到 立体脑电(SEEG)深度电极：sEEG提供了独特的测量机会 VTC和电刺激来自顶回和沟回、额叶和前部的反馈投射 颞区以及连接这些区域与VTC的白质通路。在目标1中，我们将 确定刺激这些不同的反馈位置如何影响VTC的神经元活动，并模拟 皮质柱模型中的VTC信号。VTC电极将随场景进行功能本地化 知觉任务和结构连接将通过术前弥散磁共振测量确定 关于Mayo Clinic的新型紧凑型3T扫描仪，具有高性能梯度和无失真成像。在……里面 目的2，确定VTC反馈通路的最佳刺激频率。中的电极 将用不同的时间频率刺激反馈通路，并在VTC中进行测量 用于表征最佳响应频率。在目标3中，我们将测试先前提出的 VTC的前馈驱动和反馈调制模型。我们将在传递的同时呈现视觉场景 电刺激反馈通路并测量sEEG神经反应和行为的变化 反应时间。这种电刺激和视觉感知的结合使我们能够测试和改进 VTC和顶内沟相互作用如何影响视觉加工和视觉加工的现有模型 有助于视觉感知。总体而言，这项多学科的提案将提供一套经验性的 描述反馈通路对人类VTC的因果影响的测量和模型。这些 研究将为未来的研究提供基础，以设计基于扰动的模仿策略 人类的注意力状况。

SUMMARY Visual perception is a confluence of visual input and attentional state. How visual inputs are processed and represented in human visual cortex is being captured with increasing accuracy in the field. However, a critical gap in our understanding is how top-down inputs from higher order areas influence and sculpt sensory processing—especially an understanding grounded in direct causal manipulations. The long-term goal of the proposed research is to develop causal perturbation methods that modulate visual processing in ways that mimic attentional processes. To achieve this goal, we will use electrical stimulation to test, refine, and extend a quantitative model of feedback information flow to the ventral temporal cortex (VTC). Our research leverages a recent clinical shift in epilepsy surgery from brain surface recordings with electrocorticography to stereo-electroencephalographic (sEEG) depth electrodes: sEEG provides unique opportunities to measure VTC and electrically stimulate feedback projections from gyral and sulcal parietal, frontal and anterior temporal regions as well as the white matter pathways that connect these areas to VTC. In Aim 1, we will determine how stimulating these different feedback locations affects neuronal activity in VTC and simulate VTC signals in a model of a cortical column. VTC electrodes will be localized functionally with a scene perception task and structural connections will be identified from preoperative diffusion MRI measurements on Mayo Clinic’s novel compact 3T scanner with high performance gradients and distortion free imaging. In Aim 2, we will determine the optimal stimulation frequencies for feedback pathways to VTC. Electrodes in feedback pathways will be stimulated with different temporal frequencies and measurements in VTC will be used to characterize optimal response frequencies. In Aim 3, we will test predictions of a previously proposed model of feedforward drive and feedback modulation in VTC. We will present visual scenes while delivering electrical stimulation of feedback pathways and measure changes in sEEG neural responses and behavioral reaction times. This combination of electrical stimulation and visual perception allows us to test and refine an extant model of how interactions between VTC and the intraparietal sulcus affect visual processing and contribute to visual perception. Overall, this multidisciplinary proposal will deliver a set of empirical measurements and models that describe the causal influence of feedback pathways on human VTC. These studies will provide the groundwork for future research to design perturbation based strategies that mimic human attentional conditions.