Paroxysmal staring and masticatory automatisms during postural hypotension in a patient with multiple system atrophy

We studied a 51-year-old man with multiple system atrophy and autonomic insufficiency. He had repeated episodes of loss of contact, staring, and masticatory automatisms.

Blood pressure during these events documented a systolic pressure of 60 mm Hg. Cardiovascular reflex tests provided evidence of autonomic failure. Head computed tomography (CT) revealed moderate, diffuse cortical and cerebellar atrophy.

These events were strictly related to blood pressure decreases and could be reproduced consistently by having the patient sit up after a meal. Ictal polygraphic recordings showed EEG changes consistent with anoxia, preceded by sudden hypotension with fixed heart rate.

Cerebral anoxia during a syncopal attack may therefore precipitate transient, sudden neurologic dysfunction that closely mimics complex partial seizures. Masticatory automatisms may represent a release phenomenon resulting from inactivation of neocortical structures by cerebral anoxia or reticular disconnection.