Neurometric Topographic Mapping of EEG and Evoked Potential Features: Application to Clinical Diagnosis and Cognitive Evaluation

Abstract

There is widespread agreement that topographic maps of EEG measures are difficult to evaluate unless referred to a normative data base. This raises the difficult question of how “normal” should be defined. Because the particular target of our method, which we call “neurometries,” was cognitive dysfunctions and psychiatric disorders, the instruments used to evaluate our “normal” subjects included an extensive psychiatric and neuropsychological test battery, a psychiatric as well as neurological examination, achievement tests, and determination of eye, hand, and foot dominance. Medical and psychosocial histories, pre— and perinatal data, and current and past school or work records were also evaluated. The subset of instruments used varied with age. Subjects with significant abnormal findings or events in their history which placed them at risk were excluded. Additional exclusion criteria included current use of prescription drugs, a history of head injury or loss of consciousness, any previous EEG or neurological examination, and febrile convulsions.