It's thought that almost a fifth of all American adults experience an anxiety disorder in a given year.
One anxiety disorder in particular, anticipatory anxiety, has recently been linked to sleep deprivation.
Anticipatory anxiety describes feelings of anxiousness when an individual is about to face something that has caused fear or stress in the past.
It can also be described as the body's 'fight or flight' response - adrenalin levels rise and the heart rate increases as the body prepares to react to a perceived danger.
Researchers in California have discovered that the two areas of the brain associated with anticipatory anxiety (the amygdala and anterior insula) saw significant increases in activity when study participants were deprived of sleep for just 24 hours.
Yet another reason why insomnia should never be ignored and why we need to start taking sleep health far more seriously.
Last updated: December 10, 2013