[Pathological laughing and posterior fossa tumours (author's transl)]

Abstract

Posterior fossa tumours give rise, sometimes, to psychiatric disturbances, which are difficult to diagnose, when they are isolated without any neurological signs. This was the case in our report of a 32-year-old man who had a pathological laugh, unique symptom, during 4 months, of a trigeminal neurinoma. Spasmodic laughs related to posterior fossa tumours are infrequently reported in the literature. They always are the sign of a pseudo-bulbar syndrome, due to a bilateral lesion of the cortico-bulbar tracts. Other involuntary laughs are encountered in third ventricle's lesions, in frontal lobe lesions and in epilepsy.