A slow brain wave, having a frequency of fewer than six cycles per second, that emanates from the forward portion of the brain and is associated with deep sleep in normal adults. Also called delta rhythmδ波:一种平缓的脑电波,其频率略低于每秒六个周期(6HZ)。它从前脑发出,与正常成年人的熟睡状态有关 也作 delta rhythm