Abstracts

RATIONALE: Previous research has documented cognitive impairment in the presence of mesial temporal sclerosis (MTS). However, it remains less clear which neuropsychological measures are maximally sensitive to unilateral temporal lobe pathology, and thus might be useful in predicting postoperative cognitive outcome. This study examined the utility of standardized measures of learning and memory including the recently published WMS-III in identifying material-specific memory deficits in epilepsy patients with and without MTS. METHODS: The sample included epilepsy patients with MRI-defined MTS (increased T2 signal and/or decreased hippocampal size). There were 14 left and 11 right MTS patients as well as a group without focal seizure onset as determined by EEG (n=29). Measures included the verbal Selective Reminding Test (vSRT), nonverbal Selective Reminding Test, Rey-Osterrieth Complex Figure Test, and Logical Memory (LM), Verbal Paired Associates, Faces, and Family Pictures (FamPix) subtests from the WMS-III. The three groups were comparable in terms of age, education, handedness, and Full Scale IQ. However, there was a significant gender difference with the right MTS group being comprised entirely of males (p<.001). RESULTS: A clear trend for material-specific memory impairment across all measures was observed for the patients with MTS, whereas patients in the non-focal group generally performed within normal limits. Multivariate and follow-up univariate ANOVAs revealed that the left and right MTS groups performed worse on verbal and visual memory measures, respectively (p<.05). Discriminant function analyses indicated right MTS could be predicted with an overall accuracy rate of 87.5% with Faces and FamPix being the strongest discriminating measures. Left MTS was predicted at a 79.1% accuracy rate based primarily on vSRT and LM. CONCLUSIONS: WMS-III Faces and FamPix appear to be sensitive measures in detecting right MTS, while the vSRT and WMS-III LM are slightly less sensitive in predicting left MTS. In this sample, generally average learning and memory was recorded for epilepsy patients without MTS.