The visuospatial pattern of temporal lobe epilepsy

Abstract

PurposeUnlike temporal lobe lesions, temporal lobe epilepsy (TLE) has no definite effects on visuospatial functions. This retrospective study evaluated these functions in patients with TLE, aiming to clarify their relationships to TLE laterality and magnetic resonance imaging (MRI)-detected brain lesions. MethodsThe Raven Colored Progressive Matrices (RCPM), Attentive Matrices (AM), Trail Making Test A (TMTA), Street Completion Test (SCT), Rey Complex Figure Copying (RCFC) and Delayed Reproduction (RCFDR), and Corsi Blocks Span (CBS) and Supraspan Learning (CBSSL) were used to assess different visuospatial functions in 198 patients with TLE and 90 healthy subjects. ResultsIn 169 patients (83 left), MRI revealed focal temporal lobe lesions [unilateral mesial temporal lobe sclerosis (MTLS) in 88 cases]. The patients with left or right TLE obtained normal scores on the RCPM, AM, TMTA, SCT, and RCFC, but their scores were significantly low on the CBS, CBSSL, and RCFDR. The patients with MTLS obtained lower scores in comparison with the controls and the patients without lesions, whereas those with other lesions obtained low scores only on the CBSSL and those without lesions performed normally. ConclusionsTemporal lobe epilepsy does not affect nonmemory visuospatial functions but significantly impairs visuosopatial memory and learning. This pattern is independent of TLE laterality, in keeping with a modality-specific memory model. On the contrary, the type of temporal lobe lesion is relevant to the severity of impairment.