Hypnology

Hypnology (from Greek: ύπνος, hypnos, "sleep" + -λογία, -logia, "the study of") is what the word means: the study of the mechanic, function, and technique of sleep, a state of body and mind manifested as a profound diminishment in the measurable bio-electrical activity of the nervous system and an apparent loss of consciousness, often giving rise to dreams.