RESUMEN
OBJECTIVE: Although well documented, regional brain structural abnormalities in schizophrenia are nonspecific, and morphometric parameters show significant overlapping between patients and healthy comparison subjects. An increasing number of studies have focused on supraregional models involving abnormalities of the neuronal circuitry between cortical regions in schizophrenia. The aim of the present study was to investigate cortical folding as an index of the neuronal wiring in different subtypes of schizophrenia. METHOD: Magnetic resonance imaging measures of gyrification index in intervals of 3.6 mm along the total cerebral cortex were compared in 40 patients with DSM-IV schizophrenia and 20 healthy subjects. Psychopathology was assessed with the Positive and Negative Syndrome Scale, Brief Psychiatric Rating Scale, and the Negative Symptom Rating Scale. RESULTS: The schizophrenia patients showed significantly reduced bilateral cortical folding relative to healthy comparison subjects. Such reductions were more pronounced in those with the disorganized subtype and showed an inverse correlation with negative symptoms and a positive correlation with positive symptoms. The paranoid subtype showed reduced cortical folding that was restricted to the left hemisphere. CONCLUSIONS: These results from a larger patient group confirm a previous report of reduced cortical folding in schizophrenia patients. They also suggest a distinct pattern of abnormality between schizophrenia subtypes regarding the process of cerebral lateralization and are in agreement with the neurodevelopmental hypothesis of schizophrenia.
Asunto(s)
Corteza Cerebral/anatomía & histología , Imagen por Resonancia Magnética , Esquizofrenia/diagnóstico , Adulto , Escalas de Valoración Psiquiátrica Breve , Femenino , Lateralidad Funcional , Humanos , Masculino , Escalas de Valoración Psiquiátrica , Psicología del EsquizofrénicoRESUMEN
Although well documented, brain structural abnormalities in schizophrenia are non-specific, and morphometric parameters show significant overlap between patients and healthy controls. Such inconsistencies in neuroimaging findings could represent different levels of severity along a single pathogenic process or distinct clinical and etiopathological psychoses within a schizophrenic spectrum. The aim of the present study was the investigation of distinct brain abnormalities in different subtypes of schizophrenia. Forty patients were classified according to DSM-IV and Leonhard's classifications. Psychopathology was assessed by the Positive and Negative Syndrome Scale (PANSS) and the Negative Symptom Rating Scale (NSRS). Patients were compared to 20 healthy volunteers on volumetric measures of cerebral structures (hemisphere, hippocampus and planum temporale) and ventricular-brain ratio (VBR) obtained by magnetic resonance imaging. Patients showed rightward asymmetry of cerebral hemispheres and increased VBR. Rightward asymmetry correlated with severity of negative symptoms and prevailed in the systematic forms of Leonhard, suggesting a distinct pattern of left hemisphere abnormality in this subgroup of psychoses. Increased VBR values showed a single normal distribution in the subgroups, indicating that ventricular enlargement is not restricted to a subgroup but is present to a certain degree in all cases.
Asunto(s)
Encéfalo/anomalías , Lateralidad Funcional , Imagen por Resonancia Magnética , Esquizofrenia/diagnóstico , Adulto , Ventrículos Cerebrales/anomalías , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Reproducibilidad de los ResultadosRESUMEN
Revisamos os estudos clínicos e biológicos que sugerem que os transtornos alimentares (TA) säo expressöes fenotípicas de outros transtornos psiquiátricos e parte de espectros de psicopatologia, em especial dos espectros dos transtornos do humor e do transtorno obsessivo-compulsivo. A investigaçäo da relaçäo entre os TA e outros transtornos psiquiátricos através dos modelos espectrais pode proporcionar um melhor entendimento da fisiopatologia destas síndromes e a elaboraçäo de tratamentos mais eficazes. Entretanto, o reconhecimento de que os TA possuem características peculiares e a adoçäo de uma postura crítica em relaçäo a modelos que eliminam limites diagnósticos säo também fundamentais para a evoluçäo do conhecimento no campo