Neuroimaging and fundamental symptoms in schizophrenia

The complexity of the clinical picture of schizophrenia is an essential feature of the disease that has led to attempts at organizing the symptoms and clinical course into different subtypes or grouping them into symptom constellations. Variations in response to treatment, particularly biological treatment, justifies the effort of differentiation. Various authors have tried to define primary or fundamental symptoms, that are directly related with the underlying abnormality, and secondary symptoms, which involve adaptive or reactive mechamism. Similarly, first-order symptoms, pathognomic symptoms, and second-order symptoms have been described. A constant latent problem in psychopathology is to determine the degree in which first-order symptoms are primary.