VALIDATION OF THE NES2 IN PATIENTS WITH NEUROLOGIC DISORDERS

Performance on the Neurobehavioral Evaluation System (NES) has been de monstrated to be affected by exposure to a variety of neurotoxicants. However, the relation of NES subtests to CNS function has not yet been documented in patients diagnosed with neurologic disorders known to i mplicate specific brain substrates. A validation study of the NES2 was carried out in patients with multiple sclerosis (MS) and Parkinson's disease (PD), disorders exhibiting neuropathology at loci (white matte r in MS, basal ganglia in PD) believed to be the sites of action of se veral known neurotoxicants. The results indicated that performance on certain NES2 subtests was affected in expected ways in both types of p atients. However, performance on many more subtests was impaired, rela tive to controls, in MS than in PD. The relative insensitivity to PD s uggests that expansion and refinement of the battery are required if i t is to serve well in detecting the effects of toxicants in subjects w ithout frank physical symptoms. These are the goals of a new version o f the instrument currently under development (NES3).