Hippocampal Subfield Contributions to Episodic Memory Formation: Child-Developmental Trends and Interaction with Top-down Control during Adulthood

• Applicants: Professorin Dr. Yee Lee Shing; Dr. Markus Werkle-Bergner
• Subject Area: Developmental and Educational Psychology ; General, Cognitive and Mathematical Psychology ; Human Cognitive and Systems Neuroscience
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 251512795

The hippocampal (HC) formation is a structure fundamentally important for episodic memory. However its exact functions have been underspecified due to the structural heterogeneity within the HC formation, posing technical difficulties for in vivo measurement in humans. Only recently advances in structural and functional high-resolution imaging have enabled research to document differential contributions of various hippocampal subfields to computational processes that are important for memory, including pattern separation and completion. In this context, pattern separation refers to computational operations that transform similar representations, for example derived from perception or memory, into highly dissimilar, non-overlapping representations. By contrast, pattern completion operations allow restoration of complete representations form partially available information. Initial evidence from age-comparative studies of healthy aged humans supports animal models of hippocampal aging, demonstrating that age-related reduced pattern separation processing contributes to declining acquisition of new information in aging. However, we have a weak grasp of the changes in HC structure and function during childhood, let alone the changes in HC subfields that underlie the development of pattern separation and pattern completion processes in developing children. In addition, it remains elusive in how far prefrontal control mechanisms can alter the relative propensity to engage in pattern separation/completion responses during adulthood. Accordingly, the present application proposes two sets of studies in order a) to chart the development of pattern separation and pattern completion mechanisms across hippocampal subfields, and b) to test the modifiability of those mechanisms by appropriate top-down control states during adulthood.

• DFG Programme: Research Grants