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Cognitive disorders and negative symptoms as correlates of motivational deficits in psychotic patients1

Published online by Cambridge University Press:  09 July 2009

B. Schmand ,
T. Kuipers ,
M. Van Der Gaag ,
J. Bosveld ,
F. Bulthuis  and
M. Jellema
B. Schmand*
Affiliation:
Academisch Ziekenhuis Utrecht, Department of Psychiatry, Utrecht; Slotervaartziekenhuis, Amsterdam; Psychiatric Hospital Veldwijk, Ermelo; Psychiatric Hospital Rosenburg, The Hague, The Netherlands
T. Kuipers
Affiliation:
Academisch Ziekenhuis Utrecht, Department of Psychiatry, Utrecht; Slotervaartziekenhuis, Amsterdam; Psychiatric Hospital Veldwijk, Ermelo; Psychiatric Hospital Rosenburg, The Hague, The Netherlands
M. Van Der Gaag
Affiliation:
Academisch Ziekenhuis Utrecht, Department of Psychiatry, Utrecht; Slotervaartziekenhuis, Amsterdam; Psychiatric Hospital Veldwijk, Ermelo; Psychiatric Hospital Rosenburg, The Hague, The Netherlands
J. Bosveld
Affiliation:
Academisch Ziekenhuis Utrecht, Department of Psychiatry, Utrecht; Slotervaartziekenhuis, Amsterdam; Psychiatric Hospital Veldwijk, Ermelo; Psychiatric Hospital Rosenburg, The Hague, The Netherlands
F. Bulthuis
Affiliation:
Academisch Ziekenhuis Utrecht, Department of Psychiatry, Utrecht; Slotervaartziekenhuis, Amsterdam; Psychiatric Hospital Veldwijk, Ermelo; Psychiatric Hospital Rosenburg, The Hague, The Netherlands
M. Jellema
Affiliation:
Academisch Ziekenhuis Utrecht, Department of Psychiatry, Utrecht; Slotervaartziekenhuis, Amsterdam; Psychiatric Hospital Veldwijk, Ermelo; Psychiatric Hospital Rosenburg, The Hague, The Netherlands
*
2Address for correspondence: Dr Ben Schmand, Slotervaartziekenhuis, Louwesweg, 6, 1066 EC, Amsterdam, The Netherlands
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Synopsis

The problem of a possible lack of motivation to perform cognitive tasks, which is often encountered in psychotic patients, has been approached from the perspective of the ‘energetics’ of cognition (Hockey et al. 1986) and from the broader clinical context of psychosis as an ‘amotivational syndrome’ and its related negative symptoms.

The presence of motivational deficits was investigated in a group of psychotic in-patients (N = 73, and 40 had schizophrenia) compared with a control group of non-psychotic psychiatric in-patients (N = 23). The motivational deficit was operationalized in terms of Sanders's (1983) cognitive–energetic model as a large effect of ‘time-on-task’ during a simple, monotonous reaction test. Significantly more psychotic patients than control patients showed evidence of this type of motivational deficit. The deficit appeared to be related with negative but not with positive symptoms of psychosis. Furthermore, the deficit was shown to be related to the cognitive disorders of psychosis, which have been amply documented in the literature, i.e. disorders of vigilance, verbal memory and distractibility. These results suggest that the cognitive disorders of psychosis are not of a ‘computational’ but of an ‘energetical’, i.e. motivational nature.

Type
Original Articles
Information
Psychological Medicine , Volume 24 , Issue 4 , November 1994 , pp. 869 - 884
Copyright
Copyright © Cambridge University Press 1994

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Footnotes

1

This study was presented in a preliminary form at the Biennial Winter Workshop on Schizophrenia, Badgastein, Austria, in February 1990.

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