Validity of the Minnesota Multiphasic Personality Inventory (MMPI) to psychopathology in patients with epilepsy

Information regarding the sensitivity of the Minnesota Multiphasic Personality Inventory (MMPI) to psychopathology and the meaning of MMPI elevations in neurological patients, particularly in those with epilepsy, is of both theoretical and clinical concern. Such information has a particular relevance to the temporal lobe epilepsy-psychopathology controversy. In order to investigate evidence for increased psychopathology as a function of complex partial seizures (temporal lobe epilepsy in the old nomenclature), three groups of epilepsy patients differing in seizure type were compared on the MMPI. No supportive evidence was present for such an association. Second, the sensitivity of the MMPI to psychopathology was examined by comparing three groups of epilepsy patients differing in history of psychiatric problems. The results clearly indicated that the MMPI is sensitive to psychopathology in patients with epilepsy. Finally, the Sc scale was examined in relation to items descriptive of "disease-related experiences" and the psychiatric implications of endorsing such items. About one third of the items were identified as descriptive of "real experiences." Nevertheless, patients with psychiatric histories endorsed more of such items. In conclusion, the MMPI appears to be sensitive to psychopathology in epilepsy. Therefore, insensitivity of this instrument cannot be advanced as an explanation for the results of many studies that have not supported the temporal lobe epilepsy-psychopathology controversy.