Neuronal mechanisms of adult age aifferences in visual memory: EEG and fMRI investigations of network dynamics in "repetition priming"

• Applicant: Professor Dr. Hauke Reiner Heekeren
• Co-Applicant: Professor Dr. Wolfgang Klimesch
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: from 2008 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 72209579

Mechanisms supporting learning and memory involve synchronized interactions in distributed neuronal networks comprising prefrontal, medio-temporal, and parietal areas. Normal aging affects the organization and proficiency of brain mechanisms supporting learning and memory at neurochemical, neuroanatomical, and neurofunctional levels of analysis. However, the implications of these changes for neuronal networks supporting memory and its interactions with perceptual processes are not well understood. We propose to investigate neuronal mechanisms of memory decline in normal cognitive aging by administering a repetition-priming paradigm, in which repeated presentations of familiar and unfamiliar items are followed by a surprise recognition test, to groups of young and older adults. In Experiment 1, we investigate neuronal adaptation effects as revealed by oscillatory gamma activity using EEG recordings. We predict that older adults show less synchronization of ongoing neuronal activity in perceptual and mnemonic networks than young adults, resulting in less pronounced differences between repeated exposures to familiar and unfamiliar items. In Experiment 2, we delineate processing differences between young and older adults in large-scale neuronal networks supporting visual learning and memory with high spatial and temporal resolution by combining EEG and fMRI assessments. Specifically, we examine whether increased task-relevant prefrontal activation among older adults attenuates the adverse consequences of dedifferentiated neuronal processing in early visual processing areas on memory performance (compensatory recruitment).

• DFG Programme: Research Grants
• International Connection: Austria
• Participating Persons: Professorin Shu-Chen Li, Ph.D.; Professor Ulman Lindenberger, Ph.D.