Theory of mind and perceptual context-processing in schizophrenia.
BACKGROUND
A series of studies have suggested that schizophrenia patients are deficient in theory of mind (ToM). However, the cognitive mechanisms underlying ToM deficits in schizophrenia are largely unknown. The present study examined the hypothesis that impaired ToM in schizophrenia can be understood as a deficit in context processing.


METHODS
Disorganised schizophrenia patients (N = 12), nondisorganised schizophrenia patients (N = 36), and nonpsychotic psychiatric patients (N = 26) were tested on three ToM tasks and a visual size perception task, a measure of perceptual context processing. In addition, statistical analyses were carried out which compared chronic, treatment-refractory schizophrenia patients (N = 28) to those with an episodic course of illness (N = 20).


RESULTS
Overall, ToM performance was linked to deficits in context processing in schizophrenia patients. Statistical comparisons showed that disorganised as well as chronic schizophrenia patients were more impaired in ToM but more accurate in a visual size perception task where perceptual context is misleading.


CONCLUSIONS
This pattern of results is interpreted as indicating a possible link between deficits in ToM and perceptual context processing, which together with deficits in perceptual grouping, are part of a broader dysfunction in cognitive coordination in schizophrenia.
Uhlhaas
Peter J
PJ
Max Planck Institute for Brain Research, and Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany. ulhaas@umpih-frankfurt.mpg.de
Phillips
William A
WA
Schenkel
Lindsay S
LS
Silverstein
Steven M
SM
D000328:Adult; D017668:Age of Onset; D002908:Chronic Disease; D003071:Cognition / Q000502:physiology*; D004351:Drug Resistance; D005260:Female; D006801:Humans; D007088:Illusions; D007361:Intelligence Tests; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance / Q000502:physiology; D011618:Psychotic Disorders / Q000188:drug therapy / Q000523:psychology; D012559:Schizophrenia / Q000188:drug therapy; D012565:Schizophrenic Psychology; D012858:Size Perception / Q000502:physiology; D012938:Social Perception