Naturalistic audiovisual stimulation reveals characteristic patterns of fMRI synchrony in temporal lobe epilepsy

Poster Session C - Sunday, April 14, 2024, 5:00 – 7:00 pm EDT, Sheraton Hall ABC

Chelsea Ekstrand¹ (chelsea.ekstrand@uleth.ca), Hana Abbas², Caroline Chadwick², Daniella Ladowski², Alenka Bullen², Nargess Ghazaleh², Ali R. Khan², Jorge G. Burneo², David A. Steven², Susan E. Hayman-Abello^2,3, Jonathan C. Lau², Ana Suller Marti², Terry M. Peters^2,4, Ingrid S. Johnsrude²; ¹University of Lethbridge, ²Western University, ³London Health Sciences Centre- University Hospital, ⁴Robarts Research Institute

In individuals with drug-resistant temporal lobe epilepsy (TLE), chronic seizure activity and neural reorganisation may contribute to consistent functional abnormalities in the brain. To explore the potential of movie-driven functional magnetic resonance imaging (fMRI) to identify such abnormalities, we compared neural synchrony (quantified as inter-subject correlation; ISC) as persons with TLE (n = 16) and approximately demographically matched neurotypical controls (n = 21) watched a suspenseful film clip during fMRI. Results from linear mixed effects modelling revealed significantly higher ISCs in neurotypical controls than persons with TLE across various cortical regions, including the right superior parietal lobule and inferior frontal gyrus, bilateral occipital cortices, and bilateral precuneus. Further, the TLE group exhibited significantly greater synchrony than controls in the bilateral superior temporal gyrus (STG). This was corroborated by a pilot analysis of seizure laterality, whereby both left and right TLE patients showed greater neural synchrony in the right STG compared to controls. Together, these results suggest that TLE patients show functional reorganization of the STG that may be related to altered auditory processing. More broadly, these findings provide evidence of consistent changes in functional activation associated with epilepsy and pave the way for developing models for classifying presurgical TLE patients on the basis of their neural responses to naturalistic stimulation.

Topic Area: METHODS: Neuroimaging