Lateralization of temporal lobe epilepsy and learning disabilities, as defined by disability-related civil rights law.
OBJECTIVE
Epilepsy research has identified higher rates of learning disorders in patients with temporal lobe epilepsy (TLE). However, most studies have not adequately assessed complex functional adult learning skills, such as reading comprehension and written language. We designed this study to evaluate our predictions that higher rates of reading comprehension, written language, and calculation disabilities would be associated with left TLE versus right TLE.


METHODS
Reading comprehension, written language, and calculation skills were assessed by using selected subtests from the Woodcock-Johnson Psycho-Educational Tests of Achievement-Revised in a consecutive series of 31 presurgical patients with TLE. Learning disabilities were defined by one essential criterion consistent with the Americans with Disabilities Act of 1990. Patients had left hemisphere language dominance based on Wada results, left or right TLE based on inpatient EEG monitoring, and negative magnetic resonance imaging (MRI), other than MRI correlates of mesial temporal sclerosis.


RESULTS
Higher rates of reading comprehension, written language, and calculation disabilities were associated with left TLE, as compared with right TLE. Nearly 75% of patients with left TLE, whereas fewer than 10% of those with right TLE, had at least one learning disability.


CONCLUSIONS
Seizure onset in the language-dominant hemisphere, as compared with the nondominant hemisphere, was associated with higher rates of specific learning disabilities and a history of poor literacy or career development or both. These results support the potential clinical benefits of using lateralization of seizure onset as a predictor of the risk of learning disabilities that, once evaluated, could be accommodated to increase the participation of patients with epilepsy in work and educational settings.
Epilepsy Center of Excellence, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA. gbutte@lsuhsc.edu
Grant
G
Butterbaugh
Piotr
P
Olejniczak
Betsy
B
Roques
Richard
R
Costa
Marcy
M
Rose
Bruce
B
Fisch
Michael
M
Carey
Jessica
J
Thomson
John
J
Skinner
D000328:Adult; D002961:Civil Rights / Q000331:legislation & jurisprudence*; D006233:Persons with Disabilities / Q000331:legislation & jurisprudence; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis* / Q000523:psychology; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007361:Intelligence Tests; D007807:Language Tests / Q000706:statistics & numerical data; D007859:Learning Disabilities / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D008297:Male; D008433:Mathematics; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D010358:Patient Participation; D011300:Preoperative Care; D011340:Problem Solving; D011581:Psychological Tests / Q000706:statistics & numerical data*; D012307:Risk Factors; D014481:United States / Q000453:epidemiology