Of two patients with posterior fossa tumor and pathological laughter, one had extrinsic compression of the brain stem; the other had an intrinsic brain-stem lesion. Surgical removal of the epidermoid from the cerebellopontine angle cured the laughter.
The euphoria of multiple sclerosis with paroxysmal laughter and a feeling of joy is to be differentiated from cases in which pathological laughter is a presenting complaint.
(JAMA 235:1469-1471, 1976)
Achari AN, Colover J. Posterior Fossa Tumors With Pathological Laughter. JAMA. 1976;235(14):1469-1471. doi:10.1001/jama.1976.03260400035025