We reviewed electrodiagnostic findings in patients whose electromyograph pointed toward a disorder of the central nervous system. Of the 34 patients identified, 17 did not have a clinical diagnosis of a central nervous system disorder before electromyogram. Signs suggesting a central nervous system disorder included poor activation, poor relaxation, extensor plantar responses, and flexor spasms on needle electromyogram. Ultimate central nervous system diagnoses included myelopathy, demyelinating disease, parkinsonism, tumor, and stroke.