Investigation of the differences of schizotaxic people from schizophrenic patients and healthy controls

SUMMARYThe first-degree relatives of schizophrenic patients without having psychosis mightshow similiar but milder clinical, neurophsiologic, social and neurobiologic deficits. Theconcept of schizotaxia, which was firstly used by Paul Meehl in 1962, has been reformulatedby Tsuang et al. and defined as a sydrome composed of neuropsyciologic deficits along thenegative symptoms and seen among the non-psychotic first-degree relatives of schizophrenicpatients. In our study, it is aimed to investigate the differences between the first-degreerelatives of schizophrenic patients, the ones who has determined as schizotaxic among them,and healthy individuals.In this study, 30 schizophrenic patients, 36 first-degree relatives and 30 heatlhy controlsubjects were analysed according to preliminary criteria of schizotaxia which are based on thenegative symptoms and neuropsychologic deficits. All subjects were evaluated with DSM-IVdiagnoses (Axis I and II), Global Assesment of Functioning Scale, Symptom Check List 90-R, Scale for the Assessment of Positive and Negative Symptoms, and Hamilton Anxiety andDepression Scales.Like the schizophrenic patients, the relatives of them showed some deficites in attention,verbal memory and executive functions, and showed differences from control group.Furthermore, seven of 36 relatives (19.4 %) were met the criteria of schizotaxia. The overallfunctioning of schizotaxic individuals is lower than non-schizotaxic relatives and controlgrup. On the other hand, the anxiety levels are higher than non-schizotaxic ones.To our knowledge, this is the first independent study supporting the idea which claimsthat schizotaxia is a separate syndrome. Our results is consistent with the opinion assumingthe genetic predisposition to schizophrenia among the relatives is revealed by theneuropsycologic defects. Extended studies on larger series are needed to confirm these results.