Heterogeneity in cognitive functioning of schizophrenic patients evaluated by a lexical decision task.
BACKGROUND
The disorganization pattern in schizophrenia, which involves formal thought disorders, is thought to be correlated with a deficit in integrative processes of contextual information. We tested the hypothesis that thought disordered schizophrenics, unlike non-though disordered schizophrenics, would present a deficit in the processing of the context during a task which involves these integrative processes.


METHODS
A group of 22 schizophrenic patients diagnosed in accordance with DSM-III-R criteria and a group of 11 control subjects were compared using a semantic priming version of the lexical decision task. The experimental design used low-level structuration of verbal material to reveal the difficulty that schizophrenic patients encounter in using semantic regularities.


RESULTS
A significant difference in priming effect was found between the three groups. Control subjects and non-thought disordered schizophrenics exhibit a priming effect for related word pairs when compared with unrelated pairs (respectively F(1,10) = 17.7; P < 0.002 and f(1,10) = 14.5; P > 0.003) but thought disordered schizophrenics did not (F(1,10) < 1; NS).


CONCLUSIONS
This finding provides evidence for the cognitive heterogeneity of schizophrenic subjects. This absence of priming effect in thought-disordered schizophrenic subjects supports the hypothesis that these patients present a deficit in the post-lexical controlled information processing that permits the integration of semantic information.
Passerieux
C
C
INSERM Unité de Recherche U302, Hôpital de la Pitié-Salpétrière, Université René Descartes et CNRS, Paris, France.
Segui
J
J
Besche
C
C
Chevalier
J F
JF
Widlöcher
D
D
Hardy-Baylé
M C
MC
D000328:Adult; D000704:Analysis of Variance; D003072:Cognition Disorders / Q000175:diagnosis* / Q000523:psychology; D003657:Decision Making; D005260:Female; D006801:Humans; D008297:Male; D011578:Psycholinguistics; D011930:Reaction Time; D012559:Schizophrenia / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D012660:Semantics; D014705:Verbal Behavior