Are you tired like a zombie?

This interesting article talks about the US being a nation of zombies. This nation of zombies is made up of people who are sleep deprived.

It points out that some people do not even know they are sleep deprived.

Amongst the different causes of sleep deprivation is sleep apnea, a condition that interferes with normal breathing at night, causing abnormally low levels of oxygen to be breathed in.