Connectivity dynamics related to memory consolidation in cortical layers and subcortical networks

The proposed project aims at understanding how systems level hippocampally-related functional connectivity as well as cortico-cortical microstructure changes indicative of memory engrams develop during memory consolidation. We will use a novel and unique 7T connectome magnetic resonance imaging (MRI) for humans to achieve the highest to-date possible resolution for functional and diffusion MRI. This will allow imaging of the emergence of cortico-cortical connectivity and engram-related plasticity in a layer-specific manner in early and late stages of memory consolidation, thereby narrowing the gap between an animal- and human-led understanding of memory consolidation. As neuromodulatory inputs related to more or less salient memory events are one of the most prominent drivers of the long-term stability of memories, we will additionally investigate how a stronger involvement of subcortical neuromodulatory and ‘saliency-processing structures’ affects memory consolidation. Moreover, we will assess whether semantic congruency affects the time course of dynamics in the memory consolidation network or memory engram formation.

Image Single-subject mean PET images overlaid on a T1 image. Courtesy of (Alex) Yeo Jin Yi

Archive – B06 (SFB1315/1)

Graphical Abstract: Overview of research project. We will use high resolution 7T MRI to investigate changes in the activations and interactions of brain structures known to support memory consolidation in a layer-specific manner. In doing so, we will investigate a) which structures of the memory consolidation network show higher activation and connectivity early on in memory consolidation and which structures preferentially support the retrieval of more remote memories, b) whether we can track the formation of memory engrams using layer-specific diffusion imaging, and c) whether event saliency and congruency influences dynamics in the memory consolidation network activity and memory engram formation.