Thalamocortical interactions in episodic relational memory across the lifespan

Poster Session D - Monday, April 15, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Sandra Rodriguez-Gonzalo¹ (s.rodriguez@bcbl.eu), Pedro M. Paz-Alonso¹; ¹Basque Center on Cognition, Brain and Language (BCBL)

Episodic memory relies on binding individual elements to create contexts, attending to associative, spatial and temporal dimensions of events. These relational aspects of memory have rarely been examined together within the same study and their neural substrates remain to be ascertained. While memory research has focused on the involvement of the medial temporal lobe (MTL) in binding processes and the prefrontal cortex (PFC) in supporting mnemonic control operations, higher-order thalamic nuclei may be critical in modulating the interplay between MTL and PFC during memory retrieval. Furthermore, episodic memory abilities improve rapidly during middle childhood, concomitant with PFC development, while age-related episodic memory decline is generally attributed to interference of non-relevant information along with gradual structural changes. To better understand interactions between these brain regions in relational memory over the lifespan, as well as interactions between semantic and episodic memories, twenty-three children (aged 9 to 14), twenty-two young adults (aged 18 to 35) and twenty-four elderly adults (over 60 years) underwent MRI scanning with a high-resolution functional protocol during a memory retrieval task comprising item memory as well as associative, spatial and temporal relational memory for both semantic and non-semantic materials. Results revealed a strong impact of semantic memory on episodic memory, especially for adults, which was more pronounced with age. Anterior thalamic involvement was found across retrieval conditions, differing across age groups, with functional coupling of anterior thalamus with PFC and MTL regions. These results will be discussed in line with current models on human memory development across the lifespan.

Topic Area: LONG-TERM MEMORY: Episodic