Humans spend about a third of their lives sleeping, although some people manage on much less. Thomas Edison believed that sleep was a waste of time. However, research shows that sleep deprivation can have serious consequences on memory, concentration, behaviour, mood, judgement and on overall health. The average length of sleep is 7.75 hours, although no one actually sleeps this long without interruption. In any sleep cycle, there will be periods of light and deep sleep followed by active sleep. At the end of active sleep, the sleeper may wake up, but if undisturbed will drift back to sleep again. Adults have at least five cycles of sleep at night, with each cycle lasting about 90 minutes. Babies follow a similar pattern, but the cycles are much shorter. Generally, cycle length increases with age. By the age of six months, babies may sleep for five hours or more and wake up less frequently. Very young babies will wake up at the end of a sleep cycle if they are hungry, uncomfortable or if breathing is obstructed. Research suggests waking up between cycles to be a survival mechanism. This is why parents should not feel pressured to get their new baby to sleep too long, too deeply, too soon. For most parents, the two main problems are falling asleep and staying asleep. Some babies fall asleep easily and stay asleep while others fall asleep easily, but wake up frequently. Some babies go to sleep with difficulty, but stay asleep, while others do not want to go to sleep or stay asleep. Babies that were good sleepers at six months of age may develop sleeping difficulties as they grow older and vice versa.
Sleep problems are common in babies, but understanding and knowing how to deal with them enables parents to get a better night’s sleep for themselves, which in turn enables them to provide loving, patient and consistent care for their baby.
Sleep deprivation In 1964, Californian high school student Randy Gardner set a new world record by staying awake for eleven days. After two days, Gardner experienced mood swings, concentration and memory loss. By the fourth day, he began hallucinating. Although he appeared to be in good health on the final day, research shows that chronic sleep loss increases the risk of heart disease, obesity, depression and diabetes. Even short-term sleep loss can have serious consequences. Several major industrial accidents and international nuclear disasters, such as Chernobyl and Three Mile Island, have been linked to sleep deprivation. Prolonged sleep deprivation in babies can have an effect on normal brain development resulting in decreased brain mass, nerve cell death and stunted growth. Children who do not get enough sleep, may perform poorly on creative and problem solving tasks and may have behavioural problems when they go to school. There is plenty of evidence to suggest that sleep deprivation can make children hyperactive.
Brain Activity During the initial stage of light sleep, brain waves slow and roll. During the second stage of light sleep, brain waves resemble a spindle moving across a loom. During deep sleep, brain waves deepen and dreaming may occur, although this is not as common as in active sleep. During deep sleep, pituitary hormones peak, which promote rapid brain and body growth. The fifth stage of the cycle involves active sleep. In this state, brain waves become erratic and fast. The burst of activity doubles the flow of blood to the brain, which promotes the production of nerve proteins that accelerate brain development. Nerve cells also connect with each other to set up complex networks in the brain and nervous system. Information acquired during the day is also processed, stored or discarded and certain memories are hard-wired. Areas of the baby’s brain that control sight, hearing, smell, touch, balance and movement are also active and stimulated. Scientists have recorded active sleep waves in foetuses from about 28 week’s gestation, which suggests that the brain processes experiences in utero. However, the greatest period for dreaming occurs in the first 2 weeks of life. This is hardly surprising considering the explosion of new sights, sounds, tastes, smells and textures experienced after birth.