Black-boxing the dream generator
Once in a while I'll get an indication of the inner workings of the brain, in the transition periods between sleep and wake.

The motor side of the sleep shutdown is pretty well known. During REM sleep most voluntary muscles are disconnected, which leaves them free to twitch occasionally. On waking the muscles reconnect. Some people become fully awake before the muscles turn back on, which is apparently a scary experience. And some have full muscle control while still dreaming (somnambulism.)

The sensory side isn't as well documented.

This morning I caught a specific example that can be timed fairly well. I always run a playlist of OTR shows during sleeptime. Lately most of them have been episodes of This Is Your FBI, a high-quality drama from 1945-1953. Archive.org has LOTS of episodes, which makes it an excellent playlist item. I can always find a 'new' episode to keep my thoughts tied up at the start, then run 'old' episodes during actual sleep.

Within the dream I was working along with some generic dude on a technical problem. We were trying to get some generic electronic stuff properly wired and connected. After we got everything plugged in properly, I handed him a little vial and told him I'd had this stuff made to achieve a particular aroma. What did he think of it? He opened it and said "Nothing special. Sort of meh." I laughed and said "Yeah, that's pretty much what I thought too."

At that point the little vial became a microphone and his voice became distorted like a bad public address system. He was giving directions to a "bungalow at the bottom of the hill as you approach the city."

I saw the bungalow, and then the dream went away and I slipped into wake mode. After waking I checked the playlist and listened to the currently selected program. The distorted speech had been coming from a scene in the FBI show where the agents are driving around looking for a fugitive, talking via two-way car radios. They were giving directions to a "bungalow at the bottom of the hill as you approach the city".

I know from long previous experience that audio signals are shut off or diverted at a fairly high level, because a sound that implies danger will always bust through and wake me up. Danger sounds are not necessarily loud. Anything that seems to be coming from the front door will wake me, but door knocks in the radio shows will NOT wake me. (There are a WHOLE LOT of door knocks in old radio shows!) This implies cognitive filtering. It's not just the waveform of a knock, it's some combination of realness, nearness, and location. So the shutoff is not in the outer levels of the auditory pathway, it's way up inside the cortex.

Using this morning's sequence to black-box the sensory mechanism, I can add one more piece to the diagram. The two-way radio was not a danger sound, it just happened to be present shortly before a normally scheduled wakeup. New knowledge: The dream generator knows what's coming in before it actually inserts the sound into the dream. The nonsensical business with the vial was pushed into the stack to provide a prop in Generic Dude's hand that could be turned into a microphone. The dialog about 'sort of meh' was definitely not part of a 1947 radio show, and it's not the way I talk or write.

Does this imply a gradual gate-opening that propagates up the chain, or does it imply that the dream generator somehow operates 'outside of time'?

Labels: TMI

  ¶ 3:09 AM