There is evidence to suggest that sleep-trainers may be a dangerous solution to a frequently waking baby. Encouraging a baby to sleep too deeply, too long, too soon, may interfere with the natural developmental and survival mechanisms that the baby is armed with. Sleep researchers have found that blood flow to the brain is almost doubled during light sleep and believe this is indicative of a more active brain during these periods. They believe important development takes place during light sleep. Training a baby to spend more time in a deeper sleep may therefore be damaging to the baby (Sears 2006).
W. Sears (2006). “8 INFANT SLEEP FACTS EVERY PARENT SHOULD KNOW.”