[betocmn]

Some more important conditions from the method used:

> Experimental sessions started approximately 1 to 2 hours after the last feeding

> In most cases when mothers laid the infant down, mothers held the infant with one hand behind the neck and shoulders, and the other hand under the buttocks or thighs. The mother laid the infant on its back in 18/19 samples of the 1-month-old and older infants, and 7/7 of the neonate samples, whereas one infant was laid with a sideways landing, later to be turned on its back.

>To examine the effect of sleep duration on the sleep/wake outcome, the interval between the initiations of infant sleep and laydown was calculated. The timing of the infants’ sleep onset was defined as the initiation of the behavioral sleep state, satisfying both of eye closure and no vocalization.