Pathological Laughter Prodromal to a Stroke of the Head of the Left Caudate Nucleus.

A 38-year-old right-handed female with a past history of intermittent painful rash, dizzy spells, and chronic daily headaches as well as episodic migraines experienced an episode of transient involuntary pathological laughter, right arm weakness, and expressive dysphasia. She was found on MRI to have multiple strokes in multiple vascular distributions, including one in the head of the left caudate. A cardiac ECHO found an atrial myxoma, with extensive evaluation for other causes of stroke unrevealing. The differential diagnosis for pathological laughter in this patient is discussed. The most plausible cause in this patient is an infarct to the head of the left caudate nucleus caused by an embolus of the atrial myxoma.