The state of an infant's behavior can be determined by physical monitoring. Keefe et al adapted criteria for behavior from those given by Chappell and Sander. The primary authors are associated with Childrens' Hospital and the University of Colorado in Denver.



(1) non-REM (quiet) sleep

(2) REM (active) sleep

(3) awake

(4) transition

(5) indeterminate



Behavioral Characteristics

non-REM sleep

regular breathing

eyes closed

no facial movements

no vocalization

no motor activity except an occasional reflex movement

REM sleep

irregular respirations

eyes closed with ocular motility (REM)

facial movements may occur

vocalization may occur

peripheral movements


irregular respirations

eyes open

facial movements may occur

vocalization may occur

mild or gross motor activity


regular or irregular inspirations

eyes closed with no rapid eye movement

vocalization may occur

body movement may occur

not awake (within sleep from quiet to active, or from active to quiet)


behavior of infant does not fit any of the above states



• An occasional reflex movement may include a sobbing inspiration or startle.


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