The final piece of the sleep-learning equation is memory. Children are required to memorize huge quantities of knowledge during their school days. Younger children learning to read, or older students learning a second language must memorize visually, how does a letter/word look? They must memorize phonetically, how does a letter/word sound? And they must also memorize the motor skills required to verbally produce a sound or word. Sometimes emotional connotation needs to be included in these memories as well. The brain is required to process that large number of variable stimuli that equate to new knowledge. Much of this processing, consolidation, and storage of information occurs during sleep.
Not only is sleep necessary for the efficient storage of recently acquired knowledge, sleep before learning has also been shown to be critical for the brain to encode new knowledge. Research suggests that just one night’s sleep-deprivation causes significant impairment of the hippocampus, which in turn debilitates the brain’s ability to create memories of new experiences. The child whose brain cannot effectively record memories will likely experience significant difficulty learning.
Much of the knowledge a child must ingest will be tested only by memorization, such as vocabulary, historical facts, and arithmetic. When debilitated by the inability to record new memories, a chronically sleep-deprived or sleep-restricted child may be found unable to learn at the rate required to progress normally. It seems ridiculous that a child could be identified as learning disordered simply due to lack of sleep, but research suggests that an ongoing sleep-restriction could inhibit learning ability. The implication here is that while many children do experience learning disorders, it is possible that encouraging greater sleep duration could have profound effect on memory capability.