Have you been forgetting things more frequently in the past few weeks? Do you find it difficult to take in new information, often asking someone to repeat themselves several times before you really hear what they’re saying? Are you easily distracted and making the wrong decisions? If you recognize yourself in any or all of these descriptions, you may not be getting enough sleep. And if you’re not getting enough sleep, your memory will suffer.
There are several reasons why a lack of sleep leads to poor memory. First, there’s the simple fact that if you’re tired, your body is not functioning at its highest level. Obviously, your brain is a part of your body, and if your physical state is declining then your mental state will follow. Your cells will be slow to repair themselves, and a decrease in healthy brain cells means less ability to process and store memories. Your neurons will be slower to fire; if you’re tired, you’ll react more slowly to physical stimuli, and to mental ones as well. The nutrients in your body will be stretched thin, and your brain may not get the energy it needs to work correctly. In general, both your brain’s health and your overall health will be negatively impacted by a lack of sleep.
However, even if you don’t feel the physical effects of a lack of sleep right away, you’ll still be affected by the lack of memory processing that happens when you sleep. Scientists and researchers agree that much of the process of creating memories happens while we sleep. Both long-term and short-term memories are solidified and stored during various phases of sleep. This means that not only do you need to get enough sleep, you need to make sure you’re getting the right kind of sleep. You’ll need to sleep soundly and for long enough that you experience REM sleep (when you’re dreaming) and deep sleep (also called “delta sleep” and “slow-wave sleep”). During these periods, your brain is sorting and organizing information for later recall. If you don’t experience these phases of sleep, the things you’ve learned during the day may fade away overnight, and you’ll have to start all over.
So turn out the lights, make sure you’re neither too warm nor too cold in your comfortable bed, shut off the television, computer, and radio, and let your brain get to work while you sleep.
For more information on the negative outcomes of sleep deprivation, check out the Harvard Medical School’s information pages.