Table 1 Early development (<2.4 years).

Summary of the key empirical results and theoretical tests of our model for the various ratios of sleep times in the first column during the period of early development (<2.4 years old). The second column contains the values and 95% confidence intervals for the scaling exponents as determined from direct empirical data, whereas the third through fifth columns contain the ranges of predicted values for the scaling exponents based on theories that sleep function is primarily for neural reorganization in either REM (third column) or NREM (fourth column) sleep or that it is primarily for neural repair (fifth column). The range of predicted values is calculated in each case using the three best-fit estimates for the scaling exponent α from Fig. 1. NA denotes that the corresponding theory makes no prediction for that specific variable. Predictions that match data are in bold. For these data, the predictions of the theory that sleep function during early development is primarily for neural reorganization in REM sleep are all supported, whereas the predictions of the theory that, during early development, sleep function is either primarily for neural repair or for neural reorganization during NREM sleep are all rejected.

RatioMeasured
exponent
REM reorganization
prediction
NREM reorganization
prediction
Repair
prediction
tS/tA−0.33 ± 0.07NANA0.20 to 0.60
tR/tS−0.60 ± 0.06−0.87 to −0.07NA0
tR/tA−1.00 ± 0.05−1.20 to −0.40NANA
tNR/tA0.09 ± 0.09NA−1.20 to −0.40NA