Verbal learning differences in epileptic patients with left and right temporal lobe foci.

A verbal learning test patterned after and using the same format as the Rey Auditory-Verbal Learning Test was administered to the following three groups: (1) patients with left temporal lobe epilepsy (L-TLE) as defined by EEG criteria (n = 11); (2) patients with right temporal lobe epilepsy (n = 10); and (3) normal controls (n = 11). Performance was highly similar for all three groups during the five immediate recall learning trials. The performance of the L-TLE group, averaged across three delayed recall trials (free recall, phonemic cued recall, semantic cued recall), was significantly poorer than that of the other two groups. The L-TLE group showed the worst performance on the phonemic cued recall trial, poor performance on the delayed free recall trial, and relatively intact performance on the semantic cued recall trial. Immediate and delayed free recall and phonemic and semantic cued recall for the distractor list did not discriminate groups. Word frequency, word presentation order, and concrete versus abstract words did not have different effects across groups.