David Baxter PhD
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Reasoning biases may be linked to delusions in schizophrenia
By Andrew Czyzewski
10 July 2008
Schizophr Res 2008; 102: 254-260
A tendency to jump to conclusions is associated with conviction in paranoid thoughts and the occurrence of perceptual anomalies, but not the presence of affective symptoms, a non-clinical population study shows.
The research supports the idea that reasoning biases contribute to the development and maintenance of delusions in patients with psychosis, say Daniel Freeman and colleagues from King's College London, UK.
In light of previous findings, the study also suggests that hallucinatory experiences and delusions share underlying mechanisms, possibly through dopamine dysregulation.
The researchers note that a style of reasoning that features jumping to conclusions has frequently been associated with the presence of delusions (i.e. strong beliefs resistant to change) in clinical samples of patients with psychosis.
However, there has not been a definitive study investigating jumping to conclusions and sub-clinical delusional ideation in the general population, the researchers note.
In the present study, the researchers recruited 200 members of the general public and performed the "bead task" to assess reasoning. In the test, participants requested colored beads from one of two hidden jars containing mostly yellow or mostly black beads and were asked to decide which jar was which, based on their selections. Jumping to conclusions was scored according to the number of beads requested before making a final decision.
The researchers also assessed delusional ideation using the paranoid thoughts scale, perceptual anomalies using the Cardiff anomalous perceptions scale, cognitive flexibility, and various affective symptoms.
In all, 40 (20%) participants showed definitive evidence of jumping to conclusions based on a previously verified threshold score for the bead task.
As reported in the journal of Schizophrenia Research, higher levels of conviction in paranoid ideas and experiences of perceptual anomalies were the only significant predictors of jumping to conclusions on the bead task.
Freeman and colleagues conclude that their findings are "consistent with theoretical accounts which hypothesize that both anomalies of experience and changes to decision-making processes arise from a core cognitive dysfunction underlying schizophrenia."
Abstract
By Andrew Czyzewski
10 July 2008
Schizophr Res 2008; 102: 254-260
A tendency to jump to conclusions is associated with conviction in paranoid thoughts and the occurrence of perceptual anomalies, but not the presence of affective symptoms, a non-clinical population study shows.
The research supports the idea that reasoning biases contribute to the development and maintenance of delusions in patients with psychosis, say Daniel Freeman and colleagues from King's College London, UK.
In light of previous findings, the study also suggests that hallucinatory experiences and delusions share underlying mechanisms, possibly through dopamine dysregulation.
The researchers note that a style of reasoning that features jumping to conclusions has frequently been associated with the presence of delusions (i.e. strong beliefs resistant to change) in clinical samples of patients with psychosis.
However, there has not been a definitive study investigating jumping to conclusions and sub-clinical delusional ideation in the general population, the researchers note.
In the present study, the researchers recruited 200 members of the general public and performed the "bead task" to assess reasoning. In the test, participants requested colored beads from one of two hidden jars containing mostly yellow or mostly black beads and were asked to decide which jar was which, based on their selections. Jumping to conclusions was scored according to the number of beads requested before making a final decision.
The researchers also assessed delusional ideation using the paranoid thoughts scale, perceptual anomalies using the Cardiff anomalous perceptions scale, cognitive flexibility, and various affective symptoms.
In all, 40 (20%) participants showed definitive evidence of jumping to conclusions based on a previously verified threshold score for the bead task.
As reported in the journal of Schizophrenia Research, higher levels of conviction in paranoid ideas and experiences of perceptual anomalies were the only significant predictors of jumping to conclusions on the bead task.
Freeman and colleagues conclude that their findings are "consistent with theoretical accounts which hypothesize that both anomalies of experience and changes to decision-making processes arise from a core cognitive dysfunction underlying schizophrenia."
Abstract
