Relationship between information processing speed in temporal lobe epilepsy and white matter volume.
Abnormalities in white matter have been linked to processing speed impairment in clinical populations (e.g., multiple sclerosis, closed head injury). Recent studies indicate the presence of significant reduction in cerebral white matter volume in some patients with chronic temporal lobe epilepsy (TLE). The objective of this study was to examine the relationship between white matter volume and processing speed and performance efficiency on the Sternberg Memory Scanning Test (SMST). The study groups included TLE subjects with white matter volume reduction (n=13), TLE subjects with normal white matter volume (n=14), and healthy controls (n=18). The groups did not differ in total cerebral gray matter volume. Compared with the controls, the reduced white matter volume TLE group exhibited a significantly steeper slope on the SMST. This was characterized by a disproportionate increase in reaction time with increased processing demands (set size), particularly for negative probe trials. In contrast, no significant differences on the SMST were evident between controls and the normal white matter volume TLE group. These findings suggest the presence of information processing speed and efficiency impairment in TLE and its relationship with white matter volume integrity.
Dow
Christian
C
Department of Psychology, Rosalind Franklin University of Science and Medicine, 3333 Green Bay Road, North Chicago, IL 60064, USA.
Seidenberg
Michael
M
Hermann
Bruce
B
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D004569:Electroencephalography / Q000379:methods; D004833:Epilepsy, Temporal Lobe / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011930:Reaction Time / Q000502:physiology*; D013702:Temporal Lobe / Q000473:pathology*; D013997:Time Factors