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Does the Wisconsin Card Sorting Test Measure Prefontral Function?

Published online by Cambridge University Press:  10 April 2014

Francisco Barceló*
Affiliation:
Complutense University of Madrid
*
Correspondence concerning this article should be addressed to: Francisco Barceló, Facultad de Psicología.Universidad de las Islas Baleares. Crta. Valldemossa, km 7,5. 07071 Palma de Mallorca (Spain). Fax: 34 971 17 31 90. E-mail: f.barcelo@uib.es

Abstract

This review describes a research program aimed at evaluating the validity and specificity of the Wisconsin Card Sorting Test (WCST), one of the most widely used tests of prefrontal function in clinical and experimental neuropsychology. In spite of its extensive use, voices of caution have arisen against the use of WCST scores as direct markers of prefrontal damage or dysfunction. Adopting a cognitive neuroscience approach, the present research program integrates behavioral, physiological, and anatomical information to investigate the cognitive and neural mechanisms behind WCST performance. The results show that WCST performance evokes conspicuous physiological changes over frontal as well as posterior brain regions. Moreover, WCST scores confound very heterogeneous cognitive and neural processes. This confounding effect may have led many authors to overlook the relative importance of certain dysfunctional states such as those indexed by random errors. These findings strongly suggest that WCST scores cannot be regarded as valid nor specific markers of prefrontal lobe function. However, they do provide some relevant clues to update our current knowledge about prefrontal function. In the long run, the integrative approach of cognitive neuroscience may help us design and develop more valid and sensitive tools for neuropsychological assessment.

En esta revisión se describe un programa de investigación dirigido a evaluar la validez y especificidad del Test de Clasificación de Cartas de Wisconsin (WCST), uno de los más empleados para evaluar la función prefrontal en neuropsicología clínica y experimental. A pesar de su amplio uso, han surgido voces críticas en contra de la interpretación de las puntuaciones del WCST como indicadores directos del daño o la disfunción prefrontal. Desde la perspectiva de la neurociencia cognitiva, el presente programa de investigación integra información conductual, fisiológica y anatómica para indagar los mecanismos cognitivos y neuronales subyacentes a la realización del WCST. Los resultados muestran que la ejecución del WCST va asociada a importantes cambios fisiológicos en áreas frontales y posteriores. Además, las puntuaciones del WCST mezclan procesos cognitivos y neuronales muy heterogéneos. Esta confusión puede haber inducido a muchos autores a pasar por alto la importancia relativa de ciertos estados anómalos como los asociados a los errores aleatorios. Estos hallazgos sugieren que las puntuaciones WCST no pueden ser consideradas como marcadores válidos ni específicos de disfunción prefrontal, aunque sí proporcionan claves para actualizar nuestro conocimiento actual sobre la función prefrontal. En un futuro, el análisis integrador de la neurociencia cognitiva puede ayudar a diseñar y desarrollar instrumentos de evaluación neuropsicológica más válidos y sensibles.

Type
Spanish research trends
Copyright
Copyright © Cambridge University Press 2001

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