The Advantages of a Restful Night's Sleep

The big test is in eight hours, then comes a piano recital, and it's four in the morning. Even after days of studying and playing, you still don't feel prepared for either. What can you do, then? You could have another cup of coffee, spend the next few hours studying and practicing, but dare I say it, you might be better off finishing your work, putting your music away, and going to bed. Nearly a third of our lives are spent sleeping, yet many of us pay it surprisingly little attention and care.

This omission frequently results from a serious misunderstanding. Sleep is not wasted time or merely a way to unwind after finishing our most important tasks. Instead, it serves as a vital function that your body uses to balance and control all of its internal systems, including those that control growth, immunity, and respiration.

That's great, but after this test, you can worry about all those things, right? Well, not quite yet. As you drift off to sleep, a fifth of your body's blood flow is diverted to your brain, proving that sleep is essential for your brain as well. Additionally, your brain undergoes a period of intensely active restructuring while you sleep, which is essential for how our memories are organized. Our capacity for memory doesn't initially appear to be all that impressive. The forgetting curve, which Herman Ebbinghaus first described in the 19th century, is a phenomenon whereby we typically forget 40% of new information within the first 20 minutes. However, memory consolidation, the process by which information is transferred from our ephemeral short-term memory to our more resilient long-term memory, can stop this loss.

The hippocampus, a significant portion of the brain, aids in this consolidation. Brenda Milner's research with patient H.M. in the 1950s proved its significance in the development of long-term memory. H.M.'s ability to create new short-term memories was impaired after having his hippocampus removed, but he was still able to learn physical tasks through repetition. H.M.'s capacity to create long-term memories was also harmed by the removal of his hippocampus. The hippocampus was specifically involved in the consolidation of long-term declarative memory, such as the facts and concepts you need to remember for that test, as opposed to procedural memory, such as the finger movements you need to master for that recital, which was one thing that this case revealed, among other things. Our current model of how this consolidation process functions was developed using Milner's findings as well as Eric Kandel's work from the 1990s.

Initial transcription and short-term storage of sensory information takes place in the neurons. The neurons in that cortical area are strengthened and enhanced as it continues on to the hippocampus. New synaptic buds are formed as a result of the neuroplasticity phenomenon, enabling new connections between neurons, and fortifying the neural network where the information will be retained as long-term memory. Why then do we recall some things while forgetting others? Well, there are a few ways to affect how well and to what extent memories are retained. For instance, because the hippocampus and emotion are linked, memories that are created during periods of intense emotion or even stress will be better remembered.

But as you might have guessed, getting a good night's sleep is one of the main factors promoting memory consolidation. There are four stages of sleep, with slow-wave sleep and rapid eye movement being the deepest. Electrical impulses have been observed moving between the brainstem, hippocampus, thalamus, and cortex, which act as relay stations for memory formation, on EEG machines watching people during these stages. Additionally, it has been demonstrated that various sleep stages aid in the consolidation of various memory types. Declarative memory is encoded into a temporary store in the anterior part of the hippocampus during non-REM slow-wave sleep. It is then repeatedly reactivated through a continuous exchange between the cortex and hippocampus, causing it to gradually redistribute to long-term storage in the cortex.

Contrarily, REM sleep, which resembles waking brain activity, is linked to the consolidation of procedural memory. According to the studies, the best time to go to bed is three hours after memorizing your formulas and an hour after practicing your scales. So hopefully it's clear that not getting enough sleep not only affects your long-term health but also decreases your ability to remember everything you learned and practiced the night before, which only serves to prove the wisdom of the proverb "Sleep on it." You could even say that getting enough sleep will have you waking up every morning with a new and improved brain, prepared to face the challenges ahead, when you consider all the internal restructuring and forming of new connections that occurs while you slumber.