Increased Stroop facilitation effects in schizophrenia are not due to increased automatic spreading activation

• Published in: Schizophrenia research Vol. 39; no. 1; pp. 51 - 64
• Main Authors: Barch, Deanna M, Carter, Cameron S, Perlstein, William, Baird, James, Cohen, Jonathan D, Schooler, Nina
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 23.08.1999; Elsevier Science
• Subjects: Adult; Adult and adolescent clinical studies; Automatic spreading activation; Biological and medical sciences; Cognition Disorders - diagnosis; Female; Humans; Male; Medical sciences; Middle Aged; Neuropsychological Tests; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Psychoses; Reaction Time; Schizophrenia; Schizophrenia - diagnosis; Schizophrenic Psychology; Semantic priming; Semantics; Severity of Illness Index; Stroop facilitation effects; Schizophrenia; Stroop facilitation effects; Semantic priming; Automatic spreading activation; Psychosis; Facilitation; Human; Stroop effect; Semantics; Priming effect; Information processing; Cognition
• ISSN: 0920-9964; 1573-2509
• DOI: 10.1016/S0920-9964(99)00025-0

Studies using the single trial Stroop task consistently reveal increased reaction time (RT) facilitation effects among schizophrenia patients. One possible mechanism underlying this effect is increased automatic spreading activation in semantic networks. The current study was designed to test this hypothesis. We administered the Stroop task and two semantic priming tasks to the same subjects. Patients showed greater Stroop RT facilitation than controls, no evidence of increased semantic priming at short stimulus onset asynchronies (SOAs), and reduced semantic priming at long SOAs. In addition, abnormal Stroop performance was related to the severity of Disorganization symptoms. These results are inconsistent with the spreading activation hypothesis. Alternative hypotheses regarding the source of Stroop task performance deficits in schizophrenia are discussed.