Visual binding abilities in the initial and advanced stages of schizophrenia.
OBJECTIVE
The study tests the hypothesis that intramodal visual binding is disturbed in schizophrenia and should be detectable in all illness stages as a stable trait marker.


METHODS
Three groups of patients (rehospitalized chronic schizophrenic, first admitted schizophrenic and schizotypal patients believed to be suffering from a pre-schizophrenic prodrome) and a group of normal control subjects were tested on three tasks targeting visual 'binding' abilities (Muller-Lyer's illusion and two figure detection tasks) in addition to control parameters such as reaction time, visual selective attention, Raven's test and two conventional cortical tasks of spatial working memory (SWM) and a global local test.


RESULTS
Chronic patients had a decreased performance on the binding tests. Unexpectedly, the prodromal group exhibited an enhanced Gestalt extraction on these tests compared both to schizophrenic patients and to healthy subjects. Furthermore, chronic schizophrenia was associated with a poor performance on cortical tests of SWM, global local and on Raven. This association appears to be mediated by or linked to the chronicity of the illness.


CONCLUSIONS
The study confirms a variety of neurocognitive deficits in schizophrenia which, however, in this sample seem to be linked to chronicity of illness. However, certain aspects of visual processing concerned with Gestalt extraction deserve attention as potential vulnerability- or prodrome- indicators. The initial hypothesis of the study is rejected.
Copenhagen University Department of Psychiatry, Hvidovre Hospital, Denmark.
J
J
Parnas
P
P
Vianin
D
D
Saebye
L
L
Jansson
A
A
Volmer-Larsen
P
P
Bovet
D000328:Adult; D002540:Cerebral Cortex / Q000503:physiopathology; D002908:Chronic Disease; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000209:etiology; D009483:Neuropsychological Tests; D009903:Optical Illusions; D011930:Reaction Time; D012559:Schizophrenia / Q000150:complications* / Q000175:diagnosis* / Q000503:physiopathology; D012720:Severity of Illness Index; D013028:Space Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*