Sex Differences in Pre- and Postsurgical Episodic Memory in Left Temporal Lobe Epilepsy
Abstract number :
3.438
Submission category :
11. Behavior/Neuropsychology/Language / 11A. Adult
Year :
2023
Submission ID :
1423
Source :
www.aesnet.org
Presentation date :
12/4/2023 12:00:00 AM
Published date :
Authors :
Presenting Author: Milena Gotra, PhD – Michigan Medicine/University of Michigan
Rowena Ng, PhD – Kennedy Krieger Institute; Henry Buchtel, PhD – Michigan Medicine/University of Michigan; Elise Hodges, PhD – Michigan Medicine/University of Michigan; David Marshall, PhD – Michigan Medicine/University of Michigan
Rationale:
Prior work has suggested that females with epilepsy may exhibit an advantage in episodic memory compared to males, though relatively few studies have examined how sex differences in material-specific memory may relate to performance on the Wada test. The purpose of the present study was to examine sex differences in pre- and postsurgical memory in patients with left temporal lobe epilepsy (TLE).
Methods:
This retrospective study examined data from 45 consecutive patients seen between 2013 and 2023 with left TLE and left hemispheric dominance for language (56% male, mean age=42.4, 93% White). As part of routine clinical care, all patients underwent a Wada test and comprehensive presurgical neuropsychological evaluation. A subset of 17 patients (41% male, mean age=47.2, 88% White) returned for a postsurgical neuropsychological evaluation (77% after left selective amygdalohippocampectomy).
Results:
Independent samples t-tests showed that males were younger at evaluation (Mdiff=9.8), had an earlier age of epilepsy onset (Mdiff=11.3), and were on more anti-seizure medications than females (Mdiff=.4). Controlling for demographic differences, analysis of covariance showed that sex differences in verbal memory scores were no longer significant, though females had significantly better presurgical visual delayed recall compared to males (F[1,40]=4.2, p=.04), which was associated with more spontaneous recalls (items recalled without recognition cues during the Wada) for the contralateral hemisphere (rho=.50, p=.04). Although not significant, females had higher ipsilateral Wada scores compared to males (89 vs. 79 out of 100) and relatively more females had reversed Wada memory asymmetry (55% vs. 44%), characterized by better performance in the ipsilateral compared to contralateral hemisphere. There was a similar degree of verbal memory decline among patients who returned for a postsurgical evaluation (F[1,14]=1.3, p=.28); however, despite comparable presurgical visual memory scores, females demonstrated a greater decline in visual immediate memory compared to males (F[1,14]=20.2, p< .001). Among males, fewer spontaneous recalls for the contralateral hemisphere were associated with greater decline in visual delayed recall (rho=.78, p=.04).
Conclusions:
These results suggest that while differences in verbal memory may be attributed to disease-related factors, such as age at epilepsy onset, females may exhibit an advantage in presurgical visual memory compared to males. Although our postsurgical sample was limited, the finding of visual memory decline in females postoperatively is consistent with prior work suggesting greater reliance on verbalization strategies on visual memory tasks and/or effects of suppression/crowding of right hemispheric functions following surgery in the left hemisphere. The association of spontaneous recalls with visual memory performance highlights the importance this metric may have in prediction models. Overall, these findings have potential implications for our ability to predict risk of memory decline based on neuropsychological and Wada test performance, as well as development of strategies to compensate for postoperative cognitive changes.
Funding:
None.
Behavior