Changes in episodic and semantic memory associated with temporal lobectomy

Temporal lobectomy (TL) is an effective treatment for drug refractory temporal lobe epilepsy. The main neuropsychological consequences of the intervention are changes in episodic and semantic memory. Aim. To study the consequences of right temporal lobectomy (RTL) and left temporal lobectomy (LTL) on episodic and semantic mnemonic functioning. 27 patients who had undergone TL in the Hospital Universitario Virgen de las Nieves in Granada were submitted to pre and post surgical evaluation by means of a battery of neuropsychological tests that included episodic and semantic memory tests for both verbal and visual material. ANOVA analysis was employed to analyse the pre and post surgical changes for the whole group of patients, and Student s t and Wilcoxon s non parametric test were used for each group of RTL and LTL. No deterioration was found in ipsilateral memory after the intervention, that is to say, in the verbal memory of the patients submitted to LTL and in the visual memory of RTL patients. With regard to contralateral memory, that is, the visual memory of patients submitted to LTL and the verbal memory of RTL patients, the ANOVA analyses of the whole group revealed a statistically significant improvement. The analyses performed for the whole group (LTL and RTL), however, did not reveal any statistically significant changes.