Tuesday, July 5, 2011

Why do we sleep

People think we sleep to take rest. But we can rest without sleeping. Not all of us rest while we sleep. Not surely  the heart or respiratory muscles. And if your brain rested, we won't have any dreams.

The purpose of sleep always intrigued me. And I was not alone. At least a few other people were there too. I found these two sites (big think and physorg.com) where the neuroscientists' opinion about the matter is discussed. Basically they think the reason for sleep is either :
  • information processing theory - to sort out the informations that have come in during the day (brain defragmentation?)
  • damage reversal theory - to remove free radicals and other noxious substances generated by 'heated thinking' during the day
  • adaptive inactivity theory - by UCLA neuroscientist Jerome Siegel, which says that sleep optimizes the timing of our activity.
I prescribe to the last POV. Sleep is not a physiologically necessary process. Our body can rest, take care of free radicals and organize memory without sleeping, if it needed to.

Evolutionarily it takes a lot to adapt to a particular environment. So all organisms, are adapted to one or the other kind of environment (called ecological niche). Then, at the same place, the environment changes vastly during the 24 hours a day. Animals behavior is expected to vary greatly during the day and night. For one animal, it may be difficult to be this versatile, so, nature makes it adapted to one of the time period in a day, and sleep during the other.
Pretty neat?

1 comment:

  1. excellant and clear cut explanation regarding Sleep and the theories related to it. I apreciate you Drpraveen Gopinath