noun Physiology.
- a pattern of slow brain waves, having a frequency of less than 6 cycles per second as recorded by an electroencephalograph, associated with deep sleep.
noun
- physiol the normal electrical activity of the cerebral cortex during deep sleep, occurring at a frequency of 1 to 4 hertz and detectable with an electroencephalographSee also brain wave
n.
- A brain wave pattern originating from the forward portion of the brain and having a frequency of between 1.5 and 4.0 hertz; it is associated with deep sleep in normal adults.delta wave