Poster A33, Saturday, March 25, 5:00 – 7:00 pm, Pacific Concourse
How do relational integration deficits contribute to older adults’ associative memory impairments?
Taylor James1, Audrey Duarte1; 1Georgia Institute of Technology
The rostrolateral prefrontal cortex (RLPFC) is believed to play a critical role in integrating the outputs of lower-order processes, such as evaluations of item or inter-item properties. The high-order integration functions attributed to the RLPFC have been shown to support complex reasoning. but the region’s role in episodic memory is less well understood. Emerging data suggest high-order PFC functions may be particularly susceptible to the effects of age and may contribute to older adults’ associative memory impairments. It is currently unknown how aging interferes with RLPFC operations necessary for integrating multiple relations for episodic encoding and retrieval. We investigated this issue in the current fMRI study. Young and older adults were presented with an occupation and an object and were asked to judge how likely the two were to interact, either in general or within the context of a given scene. When provided with a scene, participants needed to consider and integrate the distinct relations between the three items to reach a decision: a task dependent on RLPFC functions. fMRI data were collected during encoding and associative memory for object-occupation pairings was tested outside of the scanner. fMRI results indicated greater RLPFC activity for subsequent correct integrative than correct non-integrative trials. RLPFC recruitment was reduced in older adults, which was reflected in their poorer memory performance relative to the young. This reduced recruitment could indicate that older adults had difficulty engaging the necessary operations to encode associations as an integrated whole.
Topic Area: EXECUTIVE PROCESSES: Development & aging