Stages of Sleep : Non REM and REM Sleep Cycles Usually sleepers pass through five stages: 1, 2, 3, 4 and REM (rapid eye movement) sleep. These stages progress cyclically from 1 through REM then begin again with stage 1. A complete sleep cycle takes an average of 90 to 110 minutes, with each stage lasting between 5 to 15 minutes. The first sleep cycles each night have relatively short REM sleeps and long periods of deep sleep but later in the night, REM periods lengthen and deep sleep time decreases. Other Video in Human Physiology Difference Between Essential and Non Essential Amino Acids www.youtube.com/watch?v=Pay9GRwUCHU Why Sitting too Much is Bad for Your Health? www.youtube.com/watch?v=tV7cNYKs0w4 Functions of the Respiratory System : A Look Inside Key Respiratory Activities www.youtube.com/watch?v=1R0dMKYSD2M Functions of Calcium in the Body www.youtube.com/watch?v=bEP2R2bNdv0 Causes and Symptoms Atherosclerosis www.youtube.com/watch?v=vjew5xLr9vI The Circulatory System Function and Definition of Arteries www.youtube.com/watch?v=riKmFqp00Mw Structure and Function of Vein (Circulatory System) www.youtube.com/watch?v=C-bLhjV_WsI The Circulatory System : Anatomy and Physiology of Capillaries www.youtube.com/watch?v=U2FrnHCvQcY Blood Vessel Structure and Function (Circulatory System) www.youtube.com/watch?v=c9iyThLl1Js Composition and Function of Blood (Circulatory System) www.youtube.com/watch?v=bSqHVGS6Pzc Translated titles: Schlafstadien: nicht rem und rem Schlafzyklen नींद के चरण: गैर रिम और रिम नींद चक्र Stadiums van slaap: nie rem en rem slaap siklusse Yugto ng tulog: hindi braso at mga tuldok ng tulog sa pagtulog 수면 단계 : 비 rem과 rem 수면주기 Etapas del sueño: ciclos de sueño no rem y rem مراحل النوم: دورات نوم غير ريم وريم ঘুমের পর্যায়ে: অ রিম এবং রেড স্লাইড চক্র निद्राको चरण: गैर रिम र नींद चक्र نیند کے مراحل: غیر ریم اور ریم نیند سائیکل