DEEP SLEEP By N., Sam M.S. - 1 A stage of the sleep cycle where arousal thresholds are high. See also wave sleep. DEEP SLEEP: "Deep sleep shows up as delta waves on an EEG." Related Psychology Terms BRAIN WAVES (Electroencephalogram, EEG) DREAM-STATE (D-STATE, REM- STATE) HEARING (AUDITION) ADOLESCENCE (Theories) SLEEP STAGES RETICULAR FORMATION (Reticular Activating System, RAS) EPILEPSY (Symptoms and Types) AUDITORY THRESHOLD I PMDD: Can It Be Cured? EPILEPSY (Etiology and Therapy) Cite this page: N., Sam M.S., "DEEP SLEEP," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/deep-sleep/ (accessed January 25, 2022).