title: [The Spatial-Frequency Characteristics of the Visual System in Schizophrenia].
abstract: In order to determine the spatial-frequancy characteristics of the visual system of healthy subjects and patients with schizophrenia, we used the contrast comparison of two Gabor gratings with sinusoidal distribution of brightness. The Gabor gratings have low, medium or high spatial frequencies; the neurons of magnocellular and parvocellular channels are sensitive to these frequencies to different extents. We found an increase in sensitivity to the contrast when comparing the gratings with low frequencies (to which magnocellular channels are most sensitive) in the patients with first-episode schizophrenia who had not receive long-term antipsychotic treatment, as compared with the control group. On the contrary, the sensitivity to the gratings with medium and high spatial frequencies in this group of patients was lower, as well as in patients with first-episode schizophrenia who had received long-term treatment. The patients with chronic schizophrenia showed a decrease in contrast sensitivity in all tested ranges of frequencies. We obtained supplementary evidence of the enhancement of internal noise in the visual system of the patients with schizophrenia. The results help us to explain the clinical data on the development of visual perceptual diorders at different stages of schizophrenia.
authors.forename: I I
authors.initials: II
authors.lastname: Shoshina
authors.forename: Y E
authors.initials: YE
authors.lastname: Shelepin
authors.forename: E A
authors.initials: EA
authors.lastname: Vershinina
authors.forename: K O
authors.initials: KO
authors.lastname: Novikova
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000008:administration & dosage; D016022:Case-Control Studies; D002908:Chronic Disease; D015350:Contrast Sensitivity / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D009903:Optical Illusions; D010364:Pattern Recognition, Visual / Q000187:drug effects / Q000502:physiology; D010775:Photic Stimulation; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors; D014785:Vision, Ocular / Q000187:drug effects / Q000502:physiology*; D014795:Visual Pathways / Q000187:drug effects / Q000503:physiopathology*; D014796:Visual Perception / Q000187:drug effects / Q000502:physiology*
chemical_list: D014150:Antipsychotic Agents