1. Health
You can opt-out at any time. Please refer to our privacy policy for contact information.

Discuss in my forum



Updated February 19, 2014

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.


This technique uses a small instrument called an actigraph worn on the wrist or ankle to measure body movement. It creates a pattern based on activity that is useful in assessing sleep-wake cycles across many consecutive days and nights. It is useful for assessing advanced and delayed sleep phase disorders.

The actigraphy showed that she actually sleeps more than she thought.

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.