Brain Function in Primary Lateral Sclerosis and Amyotrophic Lateral Sclerosis

Objective: The goal of this study is to see whether patterns of cerebral cortex dysfunction differ in Primary lateral sclerosis (PLS) and amyotrophic lateral sclerosis (ALS). The function of several regions of the cerebral cortex will be assessed by clinical, physiological, and neuropsychological tests. Magnetic resonance imaging will be carried out in a subset of patients to explore the correlation between functional and anatomical measures of these cortical areas. Study Population: 30 patients with Primary lateral sclerosis who meet the diagnostic criteria for PLS proposed by Pringle and 30 patients with ALS who fulfill the revised El Escorial criteria for probable or definite ALS. 30 healthy volunteers will be studied to provide training and practice in using the rating scales and to provide age-matched controls for EEG and imaging studies. Design: A screening examination will be carried out under protocol 01-N-0145 to determine eligibility. Patients and caregivers will return for two or three visits for sessions of neuropsychological testing, a structured clinical neuropsychiatric evaluation, ratings of motor and clinical function, and measurement of movement-related cortical potentials with EEG. A subset of patients will undergo MRI scans for quantitative anatomical measures of cortical regions. Outcome Measures: The primary outcome will be the classification of patients as normal or abnormal on neuropsychological testing of frontal cortex function. Correlations of the primary outcome with other variables - clinical measures of motor function, neuropsychiatric assessment will be examined. EEG measures of movement related cortical potentials and MR imaging findings will be analyzed in an exploratory fashion to determine whether these measures differ between PLS and ALS patients.