The use of saporin conjugates to dissect neurons responsible for sleep and wakefulness

Virtually all organisms manifest regular periods of behavioral quiescence and activity. In mammals and birds, these periods have evolved into regular episodes of wakefulness and sleep. The sleep period itself has further differentiated into two distinct states, slow wave sleep (SWS) and rapid eye movement (REM) sleep. In humans, SWS has further differentiated into four distinct stages, each identified by a specific pattern on the electroencephalogram (EEG). REM sleep is very similar to wakefulness in many ways; the main difference is that there is behavioral quiescence during REM sleep. For this reason, REM sleep is often referred to as paradoxical sleep.