I'd been thinking about a sort of related topic a week or so ago -- but I couldn't remember what it was until, ironically, sleeping last night, so I thought I'd relate my thoughts real quick.
It's my theory (and this essay does a good job articulating part of it) that the brain operates at different levels of 'connectedness'. By connectedness I mean the thresholds at the synapses that determine how many neurotransmitters 'make it' in communication with the nearby neurons. I was reading an AMA from a neuropsychologist on reddit, and she mentioned that on average each neuron is connected to 70 other neurons.
So that got me thinking: when you're sleeping, it seems like one makes connections so much more easily. And wouldn't that be because the thresholds are lowered and neurotransmission between neurons is increased? So if previously 40% of your neurotransmitters were making it across the synapse for the majority of the neurons at each node connection, perhaps that level were increased to 60% throughput when you're asleep.
This would come about via dopamine or other naturally occurring hormones and proteins (in addition to drugs, which have the real risk, of course, of causingyour brain to re-normalize levels) which bind to the chemical receptors and prevent reception (threreby lowering the throughput). Other hormones regulate these hormones and increase throughput.
So to make a long story short, if sleep is a natural adaption to vary 'throughput' in the brain's graph of neurons at night -- to ease visitation and solve things at a much faster, much more 'connected' rate. Then perhaps this is an evolved tool for problem solving.
Perhaps certain problems are better solved by traversing quickly through the graph, and perhaps even during the day, as dopamine and other things are constantly adjusting in the brain, perhaps we vary out global thresholds in the brain.
So when you take a shower, or take a walk, or do some other activity, you may be changing your thresholds by 2% -- and that may allow you to see certain connections that you wouldn't otherwise. Too much 'connectedness' and it's hard to make logical sense of anything. So for the most part these thresholds are really quite high (low connectedness).
But I wonder if it isn't a sort of a model for problem solving, with various different global parameters that affect the edges' connectedness. It's sort of like having different graph visitation algorithms and then changing the edges' weights globally to try and rattle through different visitations or insights.
At any rate, this sort of dovetails with what PG was talking about (I remembered the connection initially because we'd both thought of different mental states in the shower) -- because anything that becomes the 'top idea in your mind' probably becomes a much bigger deal than we realize, because we are used to thinking that we only think with one level or global threshold parameter. But in reality when there are many levels, a big idea in mind is being visited much faster at night and in lower threshold / higher throughput times -- than we probably take for granted -- because, again, we presume that the only level of connectedness that matters is the one when we are fully 'conscious' during the day.