Face-name Learning Performance in Epilepsy Surgery Patients Suggests the Hippocampus May Not Be Essential to Learn Novel Multimodal Associations
Abstract number :
2.559
Submission category :
11. Behavior/Neuropsychology/Language / 11A. Adult
Year :
2024
Submission ID :
1509
Source :
www.aesnet.org
Presentation date :
12/8/2024 12:00:00 AM
Published date :
Authors :
Presenting Author: Erica Chen, Student – Emory University
Daniel Drane, PhD – Emory University
Rationale: We have established that the hippocampus is not required to retrieve a name, but its role in linking a name or broader semantic information with a novel face remains unknown. We hypothesized that the hippocampus would be important for making these visual-verbal associations and explored this idea by comparing the performance of pre- or post-surgical temporal lobe epilepsy (TLE) patients on the Face-Name Associative Memory Exam (FNAME). We predicted that the TLE patients who had their hippocampus ablated/resected would perform worse than patients still in the presurgical stage of evaluation if equivalent on disease-related and demographic variables, and that both groups would perform far worse than healthy controls (HCs).
Methods: The FNAME requires individuals to associate names and occupations with 12 novel faces across two learning trials. We administered the FNAME to 53 presurgical and 56 postsurgical patients evaluated at Emory University and 19 HC subjects. All presurgical patients underwent long-term video-EEG monitoring and are currently in some stage of surgical work-up. Seizure type and lateralization for all patients was based on EEG monitoring results, 3T MRI, PET scans, and NP testing. Post-surgical patients were at least one year status-post epilepsy surgery, and most underwent stereotactic laser amygdalohippocampotomy (SLAH). Table 1 contains subgroup breakdowns, and there were no subgroup differences on relevant demographic variables. Performance on the FNAME was analyzed using an ANOVA with post-hoc comparisons.
Results: All pre- and postsurgical subgroups performed worse than HCs across the various metrics of the FNAME, with most scales showing significant differences (see Table 1). Post-surgical patients performed slightly worse than presurgical patients at the group level, but the difference was not significant, and the effects sizes were very small after removing the HCs from comparison. Of note, several of the pre- and post-surgical patients showing deficits on the multimodal associational learning task did not exhibited deficits on their standard memory scores.
Conclusions: Overall, it appears that combining visual and verbal modalities of learning in an associational task may be useful in the evaluation of pre and post-surgical epilepsy candidates and will provide valuable cognitive assessment information that exceeds traditional NP measures. Contrary to our hypothesis, we did not find the post-surgical cohort to perform significantly worse than the presurgical cohort, and if this finding holds up in a pre-post single group repeated measures design, we may have to reconsider the role of the hippocampus in this area. One possible implication is that the bilateral hippocampi are redundant structures, with aspects of memory supported by a single intact hippocampus. In contrast, the current findings could also suggest that broader TL structures are contributing more significantly to multimodality associational learning. As most of our post-surgical patients received laser ablation, the preservation of language may be a contributing factor to the lack of decline following surgery as well.
Funding: NIH/NINDS (R01 NS088748)
Behavior