Hi there, it's Matt here and welcome back to this two-part series on sleep and alcohol.

Now in our last episode we learned about the three different ways in which

alcohol can harm your sleep and the first of those is unrestorative sedation rather

than naturalistic sleep. The second is sleep

fragmentation and the third is the suppression or the imperment of REM sleep.

In this episode we're going to speak about how and why alcohol

disrupts your sleep in these particular ways. Let's come back to the aspect of

sleep fragmentation. One of the problematic issues in the

underlying causes of this sleep fragmentation is that with alcohol in your

system it will activate and stimulate what we call the fight or

flight branch of your nervous system. The technical term for which is your sympathetic nervous system. I've always wondered about this by

the way. It is very poorly named your sympathetic nervous system is

anything but sympathetic.

It's very agitating and very activating.

Now, normally we have to shut down the fight or flight

branch of the sympathetic nervous system in order to fall asleep naturally

and then stay asleep soundly across the night. So in other words we have to shift away from that

fight or flight branch of the nervous system as we're getting

ready for bed and as we're falling asleep and move over into the more passive, the more

quiescent or what we call the parasympathetic nervous system.

Yet alcohol will force you back over into the fight or flight state of the

nervous system and this is one of the nervous system.

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