Angelman's (happy puppet) syndrome: clinical, CT scan and serial electroencephalographic study.

Of four patients having Angelman's syndrome admitted to a state mental facility who were clinically and electroencephalographically evaluated, 2 patients had CT scan studies of the brain. The most impressive and striking features that help in the diagnosis are the mental and physical retardation, nondevelopment of speech despite adequate visual and auditory function, various types of seizures, and episodic uncontrollable laughter. The CT scans of the brain did not offer any clue as to the pathogenesis. The EEGs appeared to fall into two groups: in one an arrest of electrical maturation occurred between ages 1 and 3 and in the other a slow but progressive maturation was evident.