We discussed last week how you can develop and sustain various sleep cycles that require less total time sleeping in order to maximize efficiency during the day. Although it is possible and theoretically practical to develop such polyphonic sleep cycles, is it really healthy to deprive your body of the amount of sleep provided by a typical sleep schedule? There are several theories as to why we actually need to sleep, but science has not been able to come to an agreement on which is absolute or if it is a combination of reasons.
The first widely acknowledged theory is the Restorative theory. This implies that the body needs sleep in order to restore and repair parts of the body that may have been worn down or damaged during waking hours. There is clear evidence backing this theory that shows how activities like muscle growth, tissue repair, growth hormone release, and protein synthesis mainly take place during sleep. This is also supported by the fact that if animals resist sleep for a certain amount of time their immune systems will completely stop performing, eventually killing them. Beyond the repair of the physical structures of the body, there are also theories regarding how the brain’s “sense of self” or “I-function” regenerates during the first stage of sleep. The prefrontal cortex of your brain’s frontal lobe is the area in charge of judgement, impulse control, visual association as well as other related activities. This area is always active in a waking person, regardless of how little sleep they have had. This area then shuts down during the first stage of sleep but boots back up again when you are dreaming in REM sleep. Since the brain is aware of itself when you are both awake and dreaming, when the prefrontal cortex is active, and unaware of itself during stage one of the sleep cycle, when the prefrontal cortex is inactive, it is logical to think that the I-function of the brain is repairing itself during this time of inactivity.
The other widely accepted theory on the necessity of sleep is the Brain Plasticity theory which posits that sleep is associated with changes and alterations in the brain’s organization. This theory is backed by research done on infants showing that a large part of their development takes place during the 13 or so hours of REM sleep they get a day. This theory also gains credence from studies on the cognitive ability of people who have been deprived of sleep. The frontal lobe, associated with speech and creative thinking, of a sleep deprived person is severely hindered. They struggle to come up with imaginative or original ideas and instead tend to repeat words and simple sayings. They also slur their speech, stutter, and struggle to cope with rapid changes or multiple tasks at once. It is possible that the reason for the importance of sleep in terms of cognitive ability is that sleep increases the production of proteins that generate neurons while decreasing the rate at which they’re broken down.
Regardless of the true reason we have to sleep, it is clear that sleep is vital to our overall wellness and health. Sleep has similar symptoms to hunger and thirst implying that it is an equally important part of our lives. Since different areas of the brain are restored during different stages of sleep, a full nights sleep is an important part of staying at 100% of mental capacity. By this thinking, in an indirect way, the more comfortable your mattress is the sharper you will be mentally since the vital parts of your sleep wont be interrupted by tossing and turning on an old lumpy mattress.