ABSTRACT
Up to 39% of children operated for a posterior fossa tumor develop the cerebellar mutism syndrome. Although they are alert and cooperative, with normal language comprehension, they are unable to speak. In addition, patients may demonstrate apathy, bladder and bowel incontinence and long-term language and cognitive disturbances. This devastating syndrome is at the same time intriguing, because it confirms a role for the cerebellum in language and cognitive functions. Recent investigations have led to new insights regarding the cerebellar mutism syndrome. The commonly accepted hypothesis states that the mutism is caused by a hypofunction of cerebral hemispheres, due to damage to the superior cerebellar peduncle and functional disruption of the cerebello-cerebral circuitry. This article focuses on the evidence for and against this hypothesis and its clinical consequences.