A failure of conflict to modulate dual-stream processing may underlie the formation and maintenance of delusions

作者：Speechley W J; Murray C B; McKay R M; Munz M T; Ngan E T C^*

来源：European Psychiatry, 2010, 25(2): 80-86.

DOI：10.1016/j.eurpsy.2009.05.012

• Delusions
• Schizophrenia
• Decision-making
• Logic
• Intuition

Background: Dual-stream information processing proposes that reasoning is composed of two interacting processes: a fast, intuitive system (Stream 1) and a slower, more logical process (Stream 2). In non-patient controls, divergence of these streams may result in the experience of conflict, modulating decision-making towards Stream 2, and initiating a more thorough examination of the available evidence. In delusional schizophrenia patients, a failure of conflict to modulate decison-making towards Stream 2 may reduce the influence of contradictory evidence, resulting in a failure to correct erroneous beliefs.
Method: Delusional schizophrenia patients and non-patient controls completed a deductive reasoning task requiring logical validity judgments of two-part conditional statements. Half of the statements were characterized by a conflict between logical validity (Stream 2) and content believability (Stream 1).
Results: Patients were significantly worse than controls in determining the logical validity of both conflict and non-conflict conditional statements. This between groups difference was significantly greater for the conflict condition.
Conclusions: The results are consistent with the hypothesis that delusional schizophrenia patients fail to use conflict to modulate towards Stream 2 when the two streams of reasoning arrive at incompatible judgments. this finding provides encouraging preliminary support for the Dual-Stream Modulation Failure model of delusion formation and maintenance.

• 出版日期2010-3