RESUMO
BACKGROUND: The regional cerebral blood flow (rCBF) response to the Wisconsin Card Sort Test (WCST) has been used to assess the functional integrity of the prefrontal cortex in patients with schizophrenia. AIMS: In this study, patients were divided into two groups according to whether they had made few or many perseverative errors on a modified version of the WCST. A control group consisted of normal volunteers. The groups were then compared with respect to rCBF response to WCST activation. METHOD: rCBF was measured during administration of a modified version of the WCST and during a card sorting control task, using single photon emission computerised tomography (SPECT). RESULTS: Performance of the modified WCST was associated with a widespread and substantial increase in rCBF, particularly in the frontal region. The poorly performing group of patients with schizophrenia showed only a modest increase in rCBF in the left anterior cingulate region. CONCLUSION: Subjects with schizophrenia are able to respond to specific neuropsychological challenge with activation of the frontal regions.
Assuntos
Circulação Cerebrovascular/fisiologia , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Encefalopatias/fisiopatologia , Estudos de Casos e Controles , Cognição/fisiologia , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/irrigação sanguínea , Fluxo Sanguíneo Regional , Psicologia do Esquizofrênico , Análise e Desempenho de TarefasRESUMO
This review discusses the current use of single photon emission computerised tomography (SPECT) for central benzodiazepine receptor imaging and quantitation. The general principles underlying SPECT imaging and receptor quantitation methods such as the kinetic, pseudo-equilibrium and steady-state (tracer infusion and bolus) approaches are described. The advantages and practical drawbacks of these techniques are highlighted.
RESUMO
Neurosyphilis continues to present in atypical forms, leading to erroneous diagnoses by physicians and psychiatrists. This patient, with a previous history of psychosis, presented in a catatonic state with rhabdomyolysis and renal failure. A subsequent breakdown was thought to be schizophrenic until unusual features led to a reassessment and discovery of neurosyphilis which was treated with penicillin and resulted in a remarkable clinical recovery.
