deep sleep

Directory

References

Discover

Vietnam War. U.S. President Lyndon B. Johnson awards the Distinguished Service Cross to First Lieutenant Marty A. Hammer, during a visit to military personnel, Cam Ranh Bay, South Vietnam, October 26, 1966. President Johnson

Vietnam War Timeline

Young men throw balloons and glitter from above the mosque at the celebration Eid Al-Fitr after prayers playing with balloons outside of Al-seddeeq mosque, Al-Mansourah, Egypt. 17 July 2015.

Black widow spider

9 of the World’s Deadliest Spiders

Albert Einstein in Washington, D.C. c. 1921-1923. Physicist

The Solar Eclipse That Made Albert Einstein a Science Celebrity

VAN, TURKEY - OCTOBER 25: A building and car ruined during the earthquake of Van-Ercis on October 25, 2011 in Van, Turkey. It is 604 killed and 4152 injured in Van-Ercis Earthquake.

What Is an Aftershock?

After a perfect launch, spectators try to catch a last glimpse of Space Shuttle Columbia, barely visible at the top end of the twisted column of smoke.

7 Accidents and Disasters in Spaceflight History

solar eclipse, sun, moon, astronomy, space

How Do You Tell the Difference Between Total, Annular, Solar, and Lunar Eclipses?

deep sleep

physiology

Learn about this topic in these articles:

study

In sleep: Light and deep sleep
Which of the various NREM stages is light sleep and which is deep sleep? The criteria used to establish sleep depth are the same as those used to distinguish sleep from wakefulness. In terms of motor behaviour, motility decreases (depth increases) from stages…
Read More