Courtney is a participant in a laboratory sleep study. her eeg begins showing small bursts of electrical activity known as sleep spindles. courtney has entered sleep.

Courtney has entered STAGE 2 SLEEP.
There are two types of sleep, REM and NON REM SLEEP. The NON REM sleep is divided into three stages, which are stages 1, 2 and 3. The stage 2 of the NON REM sleep is the most prominent sleep stage. At this stage, the EGG usually show small burst of electrical activity which is called sleep spindle.