Verbal fluency, Trail Making, and Wisconsin Card Sorting Test performance following right frontal lobe tumor resection

Abstract

Three commonly used clinical tests of frontal-executive function are verbal fluency, the Trail Making Test, and the Wisconsin Card Sorting Test, but few lesion studies of regional specificity within the frontal lobe (FL) exist for them. We examined 20 patients with right FL tumor resection, and mapped their damage to explore brain–behavior relations with greater precision. Across tests, the patients performed poorly and they also showed a deficit in switching but not clustering in verbal fluency. Within the right FL, however, we found none of the regional differences reported in studies of mixed-etiology FL patients, possibly due to the gradual neural reorganization that can occur with brain tumors. We discuss the importance of etiology in examining brain–behavior relations.

Some of these data were collected while Nicole Anderson was at the Pencer Brain Tumor Centre, Princess Margaret Hospital, Toronto. This research was supported by a fellowship from the Canadian Institutes of Health Research to P. D. and grants from Princess Margaret Hospital and the University of Toronto Faculty of Medicine Dean's Research Fund to N. A. We thank Sandra Black for use of her laboratory facilities, Dawn Nicolson for assistance with the AIR program, Marie-Eve Couture for help with figure preparation, Malcolm Binns for discussing statistical analyses, Irene Chemerensky, Dana Tobe, and Nicole Hachey for data collection, and Fern Jaspers-Fayer and Magdalena Lysenko for assistance with scoring and data entry. We also thank Donald Stuss for comments on a previous draft.

Notes

¹Note, however, that administration and scoring varies for the WCST. For example, some researchers explicitly warn patients about the rules (for comparison of warning and no-warning conditions, see Stuss et al., 2000), and whether one uses the Milner or Heaton scoring method may have some bearing on the lesion correlates of performance (see Freedman et al., 1998).

²All correlations were performed using standardized scores, or, if not available, residual scores after factoring out the influence of age.

³Of course, there may well have been regional specificity in prefrontal cortex for these tasks if we had examined patients with left hemisphere lesions, but interpretation of results from many left frontal subjects would be complicated by the likelihood of aphasia.

⁴It may even be the case that different kinds of tumors have different effects, as pointed out by an anonymous reviewer.