Differential Time-Frequency Dynamics Underlie Memory Encoding and Memory Selectivity

Poster Session E - Monday, April 15, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

Cole Williams¹, Blake Elliott², Gene Brewer¹; ¹Arizona State University, ²Temple University

The ability to preferentially encode valuable information amidst a plethora of miscellaneous information is an essential aspect of human memory. In laboratory tasks, a common finding is that higher-valued information during encoding leads to greater associative and recollective memories at retrieval. However, it is unclear if the same encoding processes that underlie memory selectivity also underlie encoding of recollective memories more generally. The current study analyzed electroencephalogram data for oscillatory activity during a value-directed remembering paradigm (VDR). During the task, participants encoded words assigned different point values with the instruction to maximize their score during test. Subjective states of recollection (i.e., “remember”) and familiarity (i.e., “know”) were assessed at retrieval. The behavioral results revealed that the value-driven gain in memory performance was selective to “remember” responses. However, analysis of oscillatory subsequent memory effects during encoding revealed a dissociation between subjective states of recollection and memory selectivity. During encoding, alpha oscillatory power in the occipital/temporal cortex displayed significantly more desynchronization for high-value compared to low-value words early during encoding. Words successfully retrieved and subsequently classified “remember” compared with words subsequently classified “know” resulted in a qualitatively different activity, including beta and theta desynchronization in later epochs. The findings suggest that, while value-directed encoding leads to increased rates of recollection, differential processes at encoding contribute to subsequent memory selectivity and the qualia of subsequent memories.

Topic Area: LONG-TERM MEMORY: Episodic