Brain waves of less than four cycles per second; the dominant pattern in a sleeping adult.
Brain wave frequency of high voltage that is characteristic of dreamless, deep sleep from which an individual is not easily aroused; also called delta wave. It is the slowest of the four brainwave patterns.
Wave pattern on an electroencephalogram typical of deep sleep.
In electroencephalography, slow waves with a frequency of 4 or fewer per second and of relatively high voltage (20 to 200 μV). It may be found over the area of a gross lesion such as a tumor or hemorrhage.