A slow brain wave which is produced in the front of the brain by adults in deep sleep, registering a frequency of 3.5 hertz.
Premature upstroke of the initial polarization of the heart; a complex of an electrocardiogram finding associated with an atrioventricular bypass tract.
Abnormal electrical waves observed in the electroencephalogram. The frequency of the normal alpha waves is 10 per second; that of the delta waves is 7 or fewer per second. They occur in the region of tumours of the brain, and in the brains of patients with epilepsy.
An abnormal deflection seen on the electrocardiogram in patients An abnormal deflection seen on the electrocardiogram in patients.