Memory Functioning in Patients with Unilateral Temporal Lobe Epilepsy: Neuroimaging Indicators of Functional Integrity in the Hippocampus and Beyond

Temporal lobe epilepsy (TLE) is a common form of intractable epilepsy that can be treated with surgical resection of the epileptogenic medial temporal lobe tissue, specifically the hippocampus. This resection can lead to a variable degree of memory deficit and considerable research has been directed at identifying predictors of these deficits. This thesis explores the relationship between structural predictors and functional predictors in TLE. I looked at fMRI activation asymmetry produced by a scene encoding task as well as volume asymmetry ratios within the hippocampus and the relationship of these predictors to memory performance in patients with TLE. Mediation analysis was performed according to Baron and Kenny (1986) and showed that fMRI activation asymmetry mediated the relationship between volume asymmetry and memory asymmetry in patients with TLE. This suggests that activation asymmetry may be a preferred variable for assessing functional adequacy in the medial temporal region.MAS