actigraphy
« Back to Glossary IndexActigraphy is used to non-invasively measure body movement. An actigraph, which looks like an oversized watch, is typically worn on the nondominant wrist (that is, if you are right-handed, you would wear it on your left wrist). It contains an accelerometer and records movements, which are then downloaded from the device and analyzed offline. When combined with a sleep diary or sleep log, actigraphy can be used to measure sleep patterns and circadian rhythms.