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

• Applicant: Professor Dr. Thomas Gruber
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: from 2008 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 72251038

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.

• DFG Programme: Research Grants