Episodic Memory Training Induces Functional Plasticity in PFC – Hippocampal Neural Circuitry
Farah Naaz1, Lindsay Knight1, Teodora Stoica1, Brendan Depue1; 1University of Louisville
Training programs for cognition are becoming more ubiquitous in mainstream society. However, there are relatively few studies exploring whether specific task related training leads to functional plasticity in the brain. Furthermore, understanding which neural regions show changes across training highlights important areas underlying the putative neural networks under investigation. We explored this question using fMRI before and after episodic memory training. Eighteen undergraduate students were recruited in a 5-day training study. Participants were scanned on day 1 and day 5. The episodic memory task and training consisted of mnemonic practice of cue-target paired associates (scenes and objects) or a single scene presented in isolation. A cued recall task (approximately 30 minutes later) required participants to either recall the name of the object when presented with the scene, or indicate if the scene was presented alone. Behaviorally, a significant increase in recall accuracy on day 5 compared to day 1 was found (Day 1= 67%; Day 5=75%). Functional analyses revealed greater activation in left ventral lateral prefrontal cortex (VLPFC), bilateral hippocampus (HC), bilateral inferior parietal sulcus (IPS), and ventral visual processing stream (VVPS) during the task (Paired > Single) on day 5 compared to day 1. Using accuracy as a regressor in functional analyses revealed positive relationships with the same regions mentioned above, but also included the dorsal attentional network. The results indicate that training leads to increased activation of the neural regions associated with encoding/retrieval, attention, and visual processing.
Topic Area: LONG-TERM MEMORY: Episodic