Functional features of the magnocellular and parvocellular systems in schizophrenia

We had studied the properties of magnocellular channels and parvocellular channels of the patients with first-episode schizophrenia and by chronic schizophrenia patients. We measured the sensitivity of the visual system by equalizing the contrast of the two Gabor gratings. This gratings was in low, or high spatial frequencies diapason, to which are sensitive magnocellular or parvocellular channels and medium to which are sensitive both. We had found that patients with a first episode of schizophrenia who did not receive long-term antipsychotic treatment, are characterized by increased sensitivity of the comparison of contrast in the range of low spatial frequencies, to which are most sensible the magnocellular channels. The sensitivity to the gratings in the range of medium and high spatial frequencies, on the contrary, had decreased. Patients with first psychotic episode, but receiving prolonged treatment, showed a decline in sensitivity of the comparison of two grating contrast over the whole range of frequencies, as well as the chronically ill. Sensitization magnocellular channels in patients with a first episode of schizophrenia who did not receive long-term antipsychotic medication helps to explain the clinical data on the changing perception of the initial stage of the development of psychosis end treatment influence.