How many hours of sleep students need and why
Neurologist, Dr. Judy Willis, M.D., M.Ed. explains the best schedule to maximize children’s health and brainpower. During sleep, the higher thinking regions of the brain are less active because information enters the brain during sleep. This is when the brain can devote a greater portion of its energy (metabolism) to organization and filing the information learned during the day. This brain state is just what is needed to allow recently learned material to be stored in long-term memory.
During the longest periods of uninterrupted deep sleep, (rather than during the "dream sleep" associated with rapid eye movement known as REM sleep) memory storage in the brain is most efficient. This is the critical time when the brain transforms recent memories into long-term memories by building and extending the branches that connect nerve cells.
The amount of information held in a single neuron is minute. It takes hundreds of neurons connected together in a memory circuit to recall even your name. Neuroplasticity is the process through which these memory circuits are constructed, connecting neurons together so their combined data becomes a memory. The major component of neuroplastic growth is the connections that extend into and out of each neuron—dendrites. Through the sprouting and connecting of these dendrites, new learning is physically linked into the larger related neural networks of memories.
Long-term memory consolidation with dendrite growth involves the building of new proteins in the memory circuits. These changes appear as increased metabolic activity on brain images in these memory storage areas during the later hours of sleep.
Dendrite branching is stimulated by the neurotransmitter serotonin secreted by the brain predominantly between the sixth and eighth hour of sleep. This correlates with the research that increasing sleep time from six or less hours to eight or more hours can increase memory and alertness up to 25 percent.
For greater test success, an extra hour of sleep may be more important than an extra hour of studying.
Studies reveal that if students review their notes thoroughly, stop, and go to sleep before or as soon as they begin to feel drowsy, the quality and quantity of retained memory is better than if they push themselves to stay awake and study the material any number of hours once drowsiness has set in. For greater test success, an extra hour of sleep may be more important than an extra hour of studying.
Harvard researchers confirmed the brain’s need for sleep to solidify the information it’s learned during the day. In a study by sleep researcher Jeffrey Ellenbogen a test group of 60 students was asked to memorize 20 pairs of random words. Half were told to return 12 hours later, after a good nights rest. The other half was told not to sleep and return in 12 hours. Of those who had slept, 76 percent correctly recalled the words on a test, while only 32 percent of the sleepless students got them right.
Scientists at the University of Pennsylvania found that mice allowed to sleep after being trained remembered what they had learned (connecting a sound to an electric shock) far better than those deprived of sleep for several hours after the conditioned learning took place.