Sleep and the first 3 months
Is sleep regression a real thing?
In the first 3 months of life infants brain develops most rapidly, there is no other time in life where the brain develops that fast!
Those changes could be disturbing for babies, with new patterns of sleeping at night. Many parents call those changes "Sleep regression". In the first 3 months of life, babies experience the highest level of REM sleep (rapid eye movement- active sleep). A full-term newborn spends 50% of their sleep time in REM sleep, premature babies 60%. The proportion of REM sleep reduced rapidly in the first months of life reaching 25% REM sleep by the age of 6 months (Gertner et al., 2002). In that time babies experience the most changes in their sleep architecture. Between 3 to 4 months most healthy infants develop circadian rhythmicity. The transition between sleep circles consists of reducing REM sleep and increasing NREM sleep. Early brain development is connected with a high level of REM sleep.
As many researchers suggest that environmental stimulation can influence the development of a neural connection between different parts of the brain. The theory suggests that REM sleep is a substitute for the environmental stimulus- eyes do not receive much stimulation in the first months of life, an infant is less alert and capable of receiving external stimulation. As the baby sensorimotor develop he doesn’t need that much REM sleep.
During the first three months of life, there is a gradual maturation of the day and night cycle.
