Defective Relationship Between Subjective Experience and Behavior ...

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and behavior abnormalities in schizophrenia was investigated. Method: Eighteen ... phrenia (paranoid: N=5; residual: N=7; disorganized: N=3; undif- ferentiated: ...
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Defective Relationship Between Subjective Experience and Behavior in Schizophrenia Jean-Marie Danion, M.D. Erick Gokalsing, M.D. Philippe Robert, M.D., Ph.D. Marilyne Massin-Krauss, M.Sc. Elisabeth Bacon, Ph.D. Objective: The relationship between subjective experience and behavior abnormalities in schizophrenia was investigated. Method: Eighteen patients with schizophrenia and 18 normal comparison subjects completed a general knowledge task with

two incentive conditions to measure monitoring effectiveness, control sensitivity, and response criterion setting. Results: The patients’ levels of monitoring effectiveness and control sensitivity were lower than those of the comparison subjects. The effect of incentives on response criterion values was similar in the two groups. Conclusions: Patients were impaired in subjectively assessing the correctness of their knowledge, and their behavior was less determined by subjective experience than that of normal subjects. The patients’ intact sensitivity to incentives has implications for cognitive remediation. (Am J Psychiatry 2001; 158:2064–2066)

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ecause conscious awareness of one’s knowledge allows behavior to be based on reflection rather than to occur as a direct response to a stimulus, impaired conscious awareness might be a critical determinant of behavior abnormalities in schizophrenia (1–3). However, the functional mechanisms underlying the relationship between a particular subjective experience and abnormal behavior are unknown. Koriat and Goldsmith (4) put forward a framework that allows investigation of these mechanisms. They posited that monitoring and control, two processes related to executive functions, play a crucial role in situations where behavior is determined by one’s knowledge. A real-life, prototypical situation is that of people who recount past events and decide what information to report. They first monitor the accuracy of recovered information. The monitoring process is expressed subjectively as a feeling of confidence that the information is correct or not. Then, subjects decide whether to volunteer or to withhold the information. The decision is based on a control process that depends on the feeling of confidence associated with the information and on the criterion for volunteering the information. The latter depends on situational demands such as motivation and incentives. The information is volunteered only if the associated confidence judgment exceeds the criterion. These processes can be assessed experimentally (4). Subjects first take a general knowledge test under forced-report instructions. They are required to answer all the questions on the test and to assess their subjective experience by providing confidence judgments regarding the correctness of each answer. Then, they repeat the task under free-report instructions and either with or without a monetary incentive for providing accurate answers. This procedure makes it possible to measure monitoring effectiveness (i.e., the ex-

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tent to which confidence judgments adequately assess the correctness of responses) and control sensitivity (i.e., the extent to which the volunteering or withholding of responses is sensitive to confidence judgments). The effects of incentives on the subjects’ control sensitivity are assessed by comparing response criteria in the no-incentive condition with that in the incentive condition. According to this framework, behavior abnormalities of patients with schizophrenia might be related to impaired monitoring of the correctness of their knowledge. Moreover, in patients with schizophrenia, subjective experience might be less strictly adhered to in controlling behavior and/or control sensitivity might be less influenced by incentives. We used Koriat and Goldsmith’s method to investigate these hypotheses.

Method Eighteen outpatients (eight women and 10 men) participated in the study (Table 1). They fulfilled DSM-IV criteria for schizophrenia (paranoid: N=5; residual: N=7; disorganized: N=3; undifferentiated: N=3). Eight patients were receiving typical neuroleptics, and 10 were receiving atypical neuroleptics. All medication was administered in a standard dose. The comparison group consisted of 18 normal subjects (eight women and 10 men). The two groups did not differ significantly in age or education. IQ, assessed with the WAIS-R, was significantly lower in patients than in comparison subjects (t=–3.51, df= 34, p