Language impairments in patients with cerebellar lesions

Abstract

In the present study language abilities in four patients with focal cerebellar lesions of different types and localized in different areas of the cerebellum were assessed before and after surgery in order to verify possible linguistic deficits and ascertain if these deficits were stable or evolved after the operation. All patients showed minor language impairments, mainly affecting morphosyntactic features and lexical access. In two patients, AZ (with an arachnoidal cyst compressing the superior portion of the vermis) and LP (with a hemangioblastoma compressing the right cerebellar hemisphere), linguistic deficits partially recovered after surgery. The remaining two patients, FR (with an astrocytoma in the vermis) and MG (with an astrocytoma compressing the left cerebellar hemisphere), did not show any improvement following the partial surgical removal of their cerebellar tumors. Minor linguistic deficits consequent to cerebellar lesions in our patients may be due to an alteration of language control processes rather than an impairment of language components. Some cerebellar structures (portions of the vermis and the cerebellar hemispheres) seem to be particularly involved in the control of language processing, and it is proposed that they accomplish this by integrating their activity with that of the so-called ‘frontal lobe system’.