Sleep has been the subject of extensive research for many years, and while our understanding of sleep and its role in good health has advanced considerably over the past few decades, there is still much we don't know about it. Presented by psychologist Steve Taylor and other experts, this program examines sleep, covering its four stages, common sleep disorders, impacts of sleep deprivation, and several theories about why humans sleep in the first place. The video also looks at treatments offered at sleep disorder clinics. Produced in Australia.

Encoded with permission for digital streaming by Infobase on August 24, 2013. Learn360 is distributed by Infobase for Films for the Humanities & Sciences, Cambridge Educational, Meridian Education, and Shopware.

Why do We Sleep? (3:29) -- Sleep Loss Experiment (3:47) -- Sleep Deprivation and Memory (1:43) -- The Nature of Sleep (3:04) -- The Nature of Sleep: Memory Consolidation (3:38) -- Not Sleeping (4:00) -- Not Sleeping: Treatment (4:48) -- Getting a Good Night's Sleep (0:46) -- Credits: Sleep: An Overview (0:31).