Spatiotemporal dynamics within memory traces studied by induced gamma-band oscillations in the human EEG and coupling measures in source space

记忆研究中一个更基本的问题是，大脑如何整合分布式存储和执行皮层区域，这些区域是激活特定“记忆痕迹”所必需的。据推测，这种集成是通过在伽马波段频率范围内（bb0 - 25Hz）的同步振荡实现的。特别是，诱导的伽马波段反应（iGBRs; ~150-400ms）可能表明概念记忆的激活，而诱发的伽马波段反应（eGBRs; ~90ms）可能反映知觉记忆。本项目的第一个目标是加深对这种记忆痕迹在内隐和外显记忆中改变的机制的认识。为此，我们将依靠刺激重复设计。第二个中心目标是通过先进的分析程序来检查特定记忆痕迹中的时空动态：(A)伽马波段源重建和(b)源空间中的功能和有效耦合措施。记忆的互补相关（erp，低频振荡）将研究它们与伽马振荡的关系。

One of the more fundamental questions in memory research is how the brain integrates the distributed storage- and executive cortical areas necessary for the activation of a specific ‘memory trace’. It is hypothesized that this integration is achieved by synchronized oscillations in the gamma-band frequency range (>25Hz). In particular, induced gamma-band responses (iGBRs; ~150-400ms) might signify the activation of conceptual engrams, whereas evoked gamma-band responses (eGBRs; ~90ms) might mirror perceptual memory.The first goal of present project is to deepen the knowledge regarding the mechanism by which such memory traces are altered during implicit and explicit memory. To that end, we will rely on stimulus repetition designs. A second central aim is the examination of the spatiotemporal dynamics within specific memory traces by means of advanced analysis procedures: (a) Gamma-band source reconstructions and (b) functional and effective coupling measures in source space.Complementary correlates of memory (ERPs, lower-frequency oscillations) will be studied in their relation to gamma oscillations.