Watch video above to see these stories on AZ Illustrated Science on Tuesday, Dec. 17:

THE POWER OF LIGHT: A look at the many ways light affects our bodies and our surroundings.

YOGA OF SLEEP: Dr. Rubin Naiman, the author of numerous works on sleep and dreams and an internationally recognized leader of integrative sleep and dream medicine, talks about his researched on dreaming and sleep.

PSYCHOLOGY OF SLEEP: Studies of human sleep have shown that sleep progresses through stages with different brain wave patters. Guests join us to discuss the psychology of sleep.

NEW APPROACH TO TRAUMA: Tucson firefighters are working with a UA trauma expert to develop POST, a new system to help prevent PTSD in survivors of traumatic events.

AZ Illustrated Science is produced by Georgia Davis. Contact her at gdavis@azpm.org.