Research has long indicated that sleep is essential to a well-performing memory. And scientists have long suspected that a lack of sleep is detrimental for reasons beyond the effect it has on a person's alertness and ability to focus during the day. What hasn't been clear is what other role(s) sleep actually plays in memory and during what sleep phase (or phases) essential memory processing occurs. For example, one long-held theory was that dreams are the brain's way of processing the day's memories and impressing traces of them on the brain's neural pathways (storing them, in other words). And research from the 1960s showed that people who don't get enough REM (dream) sleep experience memory problems when they wake up.
More recent research, especially studies using high-tech tools -- such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) -- that allow scientists to "watch" what's happening in the living brain, has begun to reveal much more information about the importance of sleep to memory. Such research suggests that it is during sleep that the brain consolidates the initially fragile memories made during the day, reinforcing them and "uploading" them, so to speak, for long-term storage. Once again our old friend the hippocampus appears to play an essential part in the process, storing the day's memories until they can be consolidated at night. The latest science also indicates that sleep facilitates or improves the brain's ability to remember both declarative information, such as facts and events, and procedural information, such as how to play the scales on a piano keyboard. The hippocampus appears to handle declarative memories, while a different brain region deals with processing procedural information. And it actually appears to be deep, slow-wave, nonRem (NREM) sleep, rather than dream sleep, that is the primary stage for consolidating memories.
Certainly, additional study is needed to confirm these latest suspicions and to help fill in the many blanks in science's understanding of the link between sleep and memory. But scientists generally agree that one important way to help your memory work at full power is to get quality sleep on a regular basis. The amount of sleep needed for performing well mentally (as well as for maintaining physical health) seems to vary among individuals but typically falls in the range of seven to nine hours each night. You may need to do some experimenting to determine the amount that seems to give you that edge. Then you need to give sleep time the importance in your schedule that other essential bodily functions require.
If you make the time for adequate sleep but have difficulty falling asleep or staying asleep for as long as you need to, there are a variety of steps you can take. To improve your mental performance -- including memory performance -- you're probably better off not using sleep-inducing medications or alcohol in an effort to get sleep, since they can leave you feeling groggy and unable to focus the next morning.
So here are some drugfree tips to help you get the shut-eye your brain needs:
- Go to bed and wake up at about the same time each day. Try to avoid the temptation to oversleep on weekends. Not only does this make it harder to get to sleep at night, but you could end up with a headache from the disruption in your sleep schedule.
- Keep your bedroom quiet and dark. Earplugs or the steady drone of an electric fan may help mask outside noises that you can't control.
- Follow the same routine each night as you prepare for bed. By setting a routine or ritual, such as washing your face and then reading for a few minutes before you retire to your bedroom, you'll start to connect these activities with sleep. They'll serve as a cue to your body that it's time to wind down and fall asleep.
- Use your bedroom only for sleep or sex. Don't read, eat, watch television, or talk on the telephone while you're in bed.
- Don't try to concentrate on falling asleep. That's a sure way to keep yourself awake. Try visualizing a relaxing scene or pleasant memory of a comfortable place.
- If you haven't fallen asleep after about 30 minutes in bed, get up and go to another room. Sit quietly, read something light, or watch something low key or boring on television for about 20 minutes. Then go back to bed. Repeat this process as necessary until you fall asleep.
On the next page, learn about diet and its effect on memory.