Clinical and neurobiological study of a schizophrenic deficit form, defined according to the Carpenter's concept

Within schizophrenia clinicians and researchers especially concentrated on negative symptoms. These negative symptoms can arise not only from the schi zophrenic process by itself(primary negative symptoms), brit also from fact ors such as depression, anxiety, neuroleptic-induced akinesia, suspiciousne ss, etc. (secondary negative symptoms). So, if they are not distinguished i n this way results of certain studies could be turned upside down. To get r ound this difficulty, Carpenter and his team have proposed the concept of d eficit syndrome whithin schizophrenia which specifies, in a schizophrenic p atient, the presence of marked; stable and primary negative symptoms. An as sessment tool called Schedule for the Deficit Syndrome (SDS) has been desig ned for the diagnostic. Results of the studies conducted with SDS, distingu ishing within schizophrenic patients, deficit and nondeficit groups, provid e a strong basis for postulating that this deficit form of schizophrenia is a distinct disease.