Relevance of the cerebellar hemispheres for executive functions

The aim of the present study was to elucidate the role of the cerebellar he mispheres in executive functions. The findings are relevant because of the large number of children who survive cerebellar tumors, Neuropsychologic as sessments of four patients (8-21 years of age) who had undergone neurosurge ry for removal of tumors in the cerebellar hemispheres were conducted and c ompared with the assessments of sis children who had been diagnosed with te mporal lobe tumors or cysts. The executive functions were assessed using th e Wisconsin Card Sorting Test, IQs were average in both groups. As expected , patients with cerebellar hemispheric lesions had impaired executive funct ions. In particular, they appeared to hare difficulty generating and testin g hypotheses regarding the matching rules on the Wisconsin Card Sorting Tes t. Patients with temporal lesions had a different pattern of deficits on th is test. The findings are consistent with the theories that propose that th e cerebellar hemispheres are involved in cognitive processes, The findings also demonstrate that subtle deficits in executive functions can be masked by a normal IQ in survivors of cerebellar tumors and highlight the need to design interventions targeted toward problem-solving skills. (C) 2000 by El sevier Science Inc. All rights reserved.