Examining the neural network dynamics underlying the temporal integration window of crossmodal perception

检查跨模态感知时间积分窗口背后的神经网络动力学

• 批准号: 505250563
• 负责人: Professor Dr. Daniel Senkowski
• 金额: --
• 依托单位: Klinik für Psychiatrie und Psychotherapie (CCM)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/505250563?language=en
• 关键词: Examining; neural; network; dynamics; underlying

Cognitive neuroscience has long sought to explain the observation that conscious perception is apparently shaped by neural processes occurring both before and after stimulus onset. Studies have revealed that neural activity preceding a stimulus influence our perception. Additionally, information that is presented within a few hundreds of milliseconds after a stimulus can still affect perception of the stimulus. We use the term postdiction to describe such backwards-oriented perceptual phenomena. Together, these findings suggest that perception is shaped by the integrative processing of information presented in a temporal window surrounding a stimulus. At the neural level, many theoretical accounts of postdiction phenomena postulate an interplay between feedback and feedforward processing. Furthermore, there is evidence that synchronized brain activity, as expressed in neural oscillations, serves as a neural mechanism that affects perception. To date, it is not well understood how neural oscillations in the temporal integration window contribute to postdiction phenomena.In this project, we will test how feedback and feedforward processes, as reflected in beta-band (13-30 Hz) and gamma-band (> 30 Hz) oscillations, respectively, as well as evoked brain responses, contribute to postdictive crossmodal perception. We will combine Bayesian causal interreference (BCI) and electroencephalography (EEG) data analysis to study the neural mechanisms underlying two crossmodal paradigms: the illusory audiovisual (AV) rabbit and the invisible AV rabbit. In these paradigms, either an illusory visual flash is induced by a subsequent audiovisual stimulus (illusory AV rabbit), or the perception of a real flash is suppressed (invisible AV rabbit). The paradigms were selected for two reasons: (i) Crossmodal processes have been previously linked to neural oscillations and they require integrative network processing. (ii) The paradigms evoke opposite percepts, i.e., inducing or suppressing a flash, and the neural mechanisms underlying these paradigms can be directly compared. We will investigate the role of neural network dynamics in oscillations and decode signatures of crossmodal postdiction from patterns of evoked brain responses. Using BCI, we will test the assumption that postdiction can arise if observers infer a common cause of the flashes and sounds. We will examine how prior causal expectations and the likelihood, i.e., the sensory evidence that a stimulus induces a particular percept in an observer, influence perception and neural processing in the two paradigms. This combined EEG-modelling project will improve our understanding about how neural network dynamics underlying the temporal integration window shape crossmodal perception.

认知神经科学长期以来一直试图解释这一观察结果，即意识知觉显然是由刺激开始前后发生的神经过程形成的。研究表明，刺激之前的神经活动会影响我们的感知。此外，在刺激后几百毫秒内呈现的信息仍然可以影响对刺激的感知。我们使用术语后置来描述这种向后导向的感知现象。总之，这些发现表明，感知是由围绕刺激的时间窗口中呈现的信息的综合处理形成的。在神经层面上，许多定位现象的理论解释假设反馈和前馈处理之间存在相互作用。此外，有证据表明，同步的大脑活动，如神经振荡所表达的，是一种影响感知的神经机制。到目前为止，人们还没有很好地理解时间整合窗口中的神经振荡是如何导致定位现象的。在这个项目中，我们将测试反馈和前馈过程，分别反映在β波段（13-30 Hz）和γ波段（bb0 -30 Hz）振荡中，以及诱发的大脑反应，如何促进后定位跨模态感知。我们将结合贝叶斯因果互参（BCI）和脑电图（EEG）数据分析来研究两种跨模态范式：虚幻视听兔（AV）和不可见视听兔（AV）的神经机制。在这些范式中，要么虚幻的视觉闪光是由随后的视听刺激引起的（虚幻的AV兔），要么对真实闪光的感知被抑制（看不见的AV兔）。选择这些范式有两个原因：(i)跨模态过程以前与神经振荡有关，它们需要综合网络处理。（ii）两种范式唤起相反的感知，即诱导或抑制闪现，并且可以直接比较这些范式背后的神经机制。我们将研究神经网络动力学在振荡中的作用，并从诱发脑反应的模式中解码交叉模态定位的特征。使用脑机接口，我们将测试假设，如果观察者推断出闪光和声音的共同原因，就会出现位置。我们将研究先验因果期望和可能性，即刺激在观察者中引起特定感知的感官证据，如何影响两种范式中的感知和神经处理。这个联合的脑电图建模项目将提高我们对神经网络动力学在时间整合窗口下如何塑造跨模态感知的理解。