The sleep states your baby had while in utero will be similar to what they will be like in the newborn period. In the first three months of life, sleep will be evenly divided between two very distinct and observable sleep states:
- Active Sleep (REM Sleep)
- Quiet/Deep Sleep (Non-REM Sleep)
The first 20-30 minutes of sleep, your infant is in an active state of sleep. This phase is referred to as a “light” state of sleep and consists of REM (Rapid Eye Movement) sleep. Babies will spend half of their time in REM sleep. The brain is replenishing itself and processing and mentally storing all your baby is experiencing throughout the day which plays a critical role in brain development. Blood is flowing to your baby’s brain bringing nutrients to active brain cells. This is an active time within the nervous system. You will be able to observe rapid eye movement under your baby’s closed eye lids when they are in this state.
Other characteristics your infant will display in light sleep are:
- Irregular Breathing
- Facial Expressions (Grimacing, puckering of lips, open/closing mouth, frowning, whimpering)
- Eye fluttering (rapid movement under eye lids)
- Sucking & body movements (twitching, startle, stretching)
- Vocalization (whimper, cry out, whine, grunt,)
- Can be Easily Awakened & Startled
Your infant will then move from Active Sleep to Quiet Sleep. This stage lasts about 20-30 minutes and takes up the other 50% of your infant’s sleep cycle. During this phase your baby is very still, eyes closed & breathes rhythmically with very little muscle movement. Most parents check frequently during this state to make sure their baby is breathing. This stage of sleep is a restoration period allowing the brain to rest. Your baby may startle during this phase but will be able to remain asleep.
Characteristics of deep sleep are:
- Still & Quiet
- Regular, shallow breathing
- Eyes closed
- No rapid eye movement
- No spontaneous movement – may startle but will remain in deep sleep
In deep sleep your baby may be able to selectively tune out sounds and bright lights. This ability to screen out overwhelming or annoying stimuli is an innate protective measure your baby has called “habituation’.
Your baby will be able to screen out sounds and over stimulating situations by shutting down. This is called habituating. When a baby is habituating – they appear to be sleeping. This protective state however consumes a lot of energy and does not replenish it as effectively as true sleep does. He may look like he is trying to sleep but in fact he is spending a great amount of energy tuning out stimulation so that he can remain asleep. An example of this is a baby that sleeps through a dinner during rush time where the restaurant is busy and crowded or the baby that seems to be passed around easily and sleeps through the handling of many relatives while at a family function. Infants who are sleeping through these types of situations are actually habituating and not truly resting.
Habituating vs. Sleeping
When newborns spend their time “shutting down” – they expend a lot of needed energy and typically wake up and become fussy and inconsolable rather than refreshed and alert. Habituation can be very draining on new babies.
Try to be observant of when your baby is habituating and know the difference of when they are shutting down vs. sleeping and waking truly rested. Some babies have a low tolerance for stimulation and are overly sensitive to environmental disruptions. These babies may have difficulty coping in loud, intrusive or overwhelming situations.
Recognizing When Your Baby is Habituating
It does not take a lot to overwhelm a new baby so pay close attention to what your baby’s tolerance level is. Try to protect their sleep by offering your infant a comfortable and quiet place to sleep. Experiment with darker, quiet areas to see if that helps protect their sleep cycles and results in better more prolonged stretches of sleep. Your baby may do better if swaddled and moved to a quiet and dimly lit or dark space in order to maintain deep sleep.