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a term for an electroencephalographic abnormality sometimes observed in infants, with random high-voltage slow waves and spikes arising from multiple foci and spreading to all cortical areas; the disorder is characterized by spasms or quivering spells, and is commonly associated with mental retardation.
hyp·sa·rhyth·mi·a, hypsarrhythmia (hip'să-rith'mē-ă),
The abnormal and characteristically chaotic electroencephalogram commonly found in patients with infantile spasms.
[G. hypsi, high, + a- priv. + rhythmos, rhythm]
hypsarrhythmia/hyp·sar·rhyth·mia/ (hip″sah-rith´me-ah) an electroencephalographic abnormality commonly associated with jackknife seizures, with random, high-voltage slow waves and spikes spreading to all cortical areas.
hypsarrhythmia(hĭp″săr-ĭth′mē-ă) [Gr. hypsi, high, + a-, not, + rhythmos, rhythm]
An abnormal electroencephalographic pattern of persistent generalized slow waves and very high voltage. Clinically it is often associated with infantile spasm and progressive mental deterioration.