[First posted on Leaderonomics.com on 7 January 2014]
[Updated: 26 May 2015]
Here’s a sure way to boost your concentration: get more sleep! When our bodies are deprived of sleep, the consequences can be dire.
Here are some broad cognitive performance effects of sleep deprivation according to a 2005 study by researchers from Emory University and the University of Pennsylvania called Neurocognitive Consequences of Sleep Deprivation:
- Involuntary microsleeps occur
- Attention-intensive performance becomes unstable with increased errors
- Time pressure increases cognitive errors
- Response time slows (a study involving a driving simulation showed that people who don’t have enough sleep drive as poorly as those who are drunk!)
- Short-term recall and working memory performances decline
- Reduced learning (acquisition) of cognitive tasks
- Performance requiring divergent thinking deteriorates
- Increased compensatory effort is required to remain behaviourally effective
- Tasks may be begun well, but performance deteriorates as task duration increases
- There is growing neglect of activities judged to be nonessential (loss of situational awareness)
There is overall effect on quality of life as well. The Guide to Healthy Sleep by the National Institutes of Health says animal studies suggest that sleep is just as important as food.
Rats, that normally live for two to three years, experience rapid decline in lifespan if they don’t get enough sleep. When they lack REM (rapid eye movement) sleep, they live for only five weeks.
When they are deprived of all sleep stages, they live only two to three weeks. This is “a timeframe similar to death due to starvation,” it writes.
There are suggestions of similarities between lack of sleep and aging as well. When there is extreme sleep deprivation, such as one study where young individuals were deprived of sleep for 36 hours, cognitive performance of the young subjects deteriorated to the level of the elderly.
So here’s the big question. How much sleep do we need? It varies according to age and also individuals. Some adults can function well with seven hours per night, while others need nine or more.
Teenagers need between nine and 10 hours of sleep. At this age, there is a tendency to sleep later at night, and, therefore, a desire to wake up later in the morning. The Guide to Healthy Sleep points out the conflict when teenagers have to wake up early for school, and don’t get the hours they need.
To those with concentration problems, Vatsal G. Thakkar, MD, clinical assistant professor of psychiatry at New York University School of Medicine advises sleeping seven to nine hours a night for at least two weeks. If nothing improves, Thakkar advises seeing a sleep specialist.
The cycle of sleep
But while length of sleep is important, understanding the stages of sleep is crucial as well. Researchers and medical practitioners commonly attribute impairment of the ability to focus to the lack of deep sleep (stage three of non-REM sleep). There are two types of sleep: non-REM and REM sleep:
1. Non-REM Sleep
- Stage 1 (N1):
Light sleep; easily awakened; muscles relax with occasional twitches; eye movements are slow.
- Stage 2 (N2):
Eye movements stop; slower brain waves, with occasional bursts of rapid brain waves.
- Stage 3 (N3):
Occurs soon after you fall asleep and mostly in the first half of the night. Deep sleep; difficult to awaken; large slow brain waves, heart and respiratory rates are slow and muscles are relaxed.
2. REM Sleep
- Usually first occurs about 90 minutes after you fall asleep, and longer, deeper periods occur during the second half of the night; cycles along the non-REM stages throughout the night.
- Eyes move rapidly behind closed eyelids.
- Breathing, heart rate, and blood pressure are irregular.
- Dreaming occurs.
- Arm and leg muscles are temporarily paralysed.
Source: Your Guide to Healthy Sleep, National Institutes of Health
These sleep stages form a cycle, which repeats as you sleep. Here’s are the dynamics and stages of a typical seven-hour sleep by Melinda Smith, Lawrence Robinson, and Robert Segal of lifeguide.org. Each cycle typically lasts 90 minutes and it repeats four to six times over the course of a night:
You’ll notice that the length of each sleep stage varies as time progresses. N3, or deep sleep, is what researchers say is essential for restoring your body and ensuring you are energetic the next day. REM sleep, where dreaming occurs, stimulates the regions of your brain that you use to learn and make memories.
So to increase alertness, sharpness, and ensure your decision making abilities are in tip-top shape, appreciate and make the most out of your snooze time. Give your body and brain the rest and time it needs to restore and regenerate, and you should be on your way to a more alert you this year.