Naming and word retrieval deficit in temporal lobe epilepsy

This investigation evaluated the hypothesis that patients with late onset of left temporal lobe epilepsy (late LTLE) display increased word finding difficulties than other temporal lobe epilepsy patients and normal subjects. Thirty-two epilepsy patients and eight normal control subjects were recruited. The epilepsy patients were grouped by side (left vs. right) of epileptic focus and onset of epilepsy (before age five vs. later), with eight patients enrolled in each group. Groups were matched as closely as possible for age, education, estimated IQ, and memory ability, and all subjects were required to have normal language functioning as measured by the Western Aphasia Battery (WAB AQ).; Results showed that the late LTLE group performed significantly worse than the other epilepsy groups on the WAB AQ, despite their normal language functioning. Other naming and word finding measures did not demonstrate significantly poorer word retrieval in the late LTLE group. An examination of latency showed that the late LTLE group exhibited a significantly longer latency than the other epilepsy groups on the WAB. To determine whether the stimulus modality used in examining word finding would distinguish the late LTLE group from the other epilepsy groups, an analysis of the visual versus the auditory stimulus modality was conducted. No significant group differences were observed. Despite the general lack of significant group differences on the standardized measures, it is the investigator's impression that clinical judgement is highly accurate in localizing epileptic foci. Thus, group differences on standardized measures do not appear to be useful in detecting word finding difficulties in epilepsy patients. It is recommended that other, more novel approaches for detecting word finding difficulties in epileptic patients need to be developed.