Where did I leave my glasses?

: the relationship between semantic and episodic memory in healthy aging

Abstract

Extensive research has described the distinction between semantic memory and episodic memory (e.g., Tulving, 1972). Despite the neurocognitive dissociation between these two memory systems, they often interact. Several studies indicate that semantic knowledge facilitates the retrieval of episodic memories in both young adults and amnesic patients. A well-documented finding is the semantic congruency effect wherein participants display better episodic memory for information that is compatible, rather than incompatible, with their pre-existing semantic knowledge. However, there are divergent results concerning the semantic congruency effect on older adults’ episodic memory, and whether that same facilitation is observed is still an open question. Taking this into account, the present study explored the role of semantic memory in the retrieval of episodic memories in healthy older adults in relation to young adults. Particularly, we sought to investigate if and how the congruency between new information to be memorized and previous semantic knowledge enhances episodic memory. For this purpose, we tested item and associative memory (manipulating the congruency of both target objects and distractors) using a recognition memory paradigm with object-scene pairs. The results showed that older adults had worse episodic memory performance than young adults, both in item memory and associative memory. Also, a semantic congruency effect was found in both groups in the item memory task. In the associative memory task, the two groups performed better when the target object was congruent than incongruent and had worse performance for congruent distractors than incongruent ones. Still, older adults benefited more than young adults when the target object was congruent with the scene than when it was incongruent and, on the other hand, were more impaired than young adults when the distractor was congruent than incongruent. Therefore, we suggest that older adults’ tendency to choose congruent relationships corroborates the importance of semantic schema and its inflexibility in aging.

Date of Award	21 May 2020
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Filipa Ribeiro (Supervisor) & Ana Luísa Raposo (Supervisor)