Spatial navigation impairment in patients with refractory temporal lobe epilepsy: evidence from a new virtual reality-based task.

This study was aimed at examining spatial learning and memory in nonoperated temporal lobe epilepsy (TLE). Twenty-five patients with a refractory epileptic focus located in the temporal lobe (10 in the right hemisphere and 15 in the left hemisphere) and 25 healthy age-matched controls performed the "Boxes Room," a virtual reality version of the holeboard. They were trained in 10 trials to locate the reward boxes in a room with 16 of them available. Participants also completed a comprehensive neuropsychological evaluation. Patients performed significantly worse relative to the control group. They traveled longer distances and committed more errors than controls. No differences in performance were found within the TLE group when gender or lateralization of the epileptic focus was considered an independent variable. These findings suggest that the integrity of temporal structures in both hemispheres could be critical to spatial learning and memory and support the spatial component of the task.