While falling back asleep I have been noticing the sound of the fan becoming quieter to the point that I can't hear it at all. When this starts to happen I wake back up and it's like someone is slowly rotating a volume knob louder. I think it's incredible that I'm at this stage of consciousnesses to perceive it. It's actually a really incredible feeling because I know it's my brain filtering out the sounds and not just my ears going bad! So I did some Google searches and have the assumption it's related to "sleep spindles". Check this out:
The pulses in sleep spindles can change their rate as well which could essentially be the "volume knob" effect I'm hearing. So cool!Spindles are quick brain pulses that occur during the otherwise slow-wave sleep. Spindles are generated by the thalamus, which relays communication signals and external stimuli to the cortex, where the signals are processed. Spindles prevent these signals from even reaching the thalamus.
When I got up and ran to the computer to write this post I started thinking how interesting it would be to have that level of control through a fully conscious mind, wide awake. This might be common knowledge for some of you but I thought it was pretty rad and wanted to share.
If you would like to check out one of the articles I was browsing over this morning here is a start:
http://newsdesk.org/2010/08/scientist-s ... -spindles/