Sleep Patterns



Dr. Phyllis C. Zee, M.D., Ph.D. explains the body’s sleep-wake cycle and discusses how to track your sleep patterns.
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Our sleep patterns, known as circadian rhythms, are driven by relays from specialized brain circuits. These circuits function as a sort of switch, flip-flopping between triggering our need to "fall asleep" as well as our unconscious desire to "pop awake". In addition, the brain also maintains a 24-hour internal biological clock. This clock is affected by light, as well as other behavioral cues, such as when food is available.

These and other scientific insights enable doctors to have a better understanding of the brain, the types of new medication that can induce sleep, and how to manage the sleep/wake cycle more effectively.

One reliable way to pinpoint your sleep problems is to monitor your sleep patterns. An easy way to do this is to keep a sleep diary to track your sleep (or lack of sleep) over a 7-day period. It can help you uncover sleep patterns and document things like how often you awoke during the night, how many hours you slept, etc. After the seven days, you will have a detailed picture of your sleep habits. With all of the facts in front of you, it will be easier for you and your healthcare provider to detect patterns that can help you both diagnose your sleep problems.

Although your completed diary should provide valuable insights, your sleep problems may be more complex than the diary reveals. For this reason, it's always a good idea to talk to your doctor about your sleep difficulty.

How to use the Sleep Diary

Each day's sleep log takes only a few minutes to complete.

  • Print out a blank diary
  • Answer the first six questions each morning when you wake to start your day
  • Answer the remaining three questions each night before bedtime
  • Enter your answers consistently for seven days
  • Share the completed diary with your physician

Download the sleep diary

Sleep patterns and aging

Contrary to popular perception, older adults do not need less sleep as they age. Like younger adults, they require between seven and nine hours of sleep nightly. But, even though our sleep needs change little through adulthood, our patterns of sleeping tend to change as we age. Older adults tend to spend less time in deep (slow-wave) sleep and more time in non-rapid eye movement (NREM) sleep, which, in turn, may cause more frequent waking throughout the night. Our internal clocks also advance as we age, causing us to wake earlier in the morning and feel more tired earlier in the evening.

Next: Stages Of Sleep