Last week we learned that hitting the snooze button when your alarm goes off is not such a good idea because you will feel less rested than when you get up straight away. For waking up rested a consistent sleep schedule is recommended. But how much is enough sleep and if you do not get enough can you ever catch up on it?
In an experiment reported on AsapSCIENCE researchers assigned people to three groups that slept different amounts of time each night for an extended period of time: four, six, or eight hours. After two weeks, those with eight hours of sleep experienced few attention lapses and cognitive issues. However, those with six hours showed cognitive performance equal to drunk people and those with four hours of sleep even sometimes fell asleep during their cognitive tasks. The latter two groups showed a steady decline in brain functioning across the two weeks.
Several studies seem to point to the fact that seven to eight hours of sleep is optimal. Sleeping not enough or too much over an extended period of time can lead to severe health problems. However, the right amount of sleep also seems to depend on genetic disposition und thus may vary from individual to individual.
Not getting enough sleep is called sleep debt. Research shows that one can catch up on one or two nights of sleep debt. However, when there are extended periods of time with not enough sleep it takes weeks or even months to regain the original brain power. At the same time people become less and less aware of their impairment.
Thus, generally seven to eight hours of sleep seem to be healthy. However, there is still quite a bit of controversy amongst researchers on this, just like on the mechanism underlying sleep. Moreover, there seem to be inter-individual differences in the ideal amount of sleep. We will dig deeper into this!