>So it seems very spooky on its face that somehow thoughts themselves could have a bidirectional relationship with chemistry.

There's no scientific reason to believe thoughts affect the chemistry at all. (Currently at least, but I'm not betting money we'll find one in the future).

When Scott Alexander talks about feedback loops like bipolar disorder and sleep, he's talking about much higher level concepts.

I don't really understand what the parent comment quote is trying to say. Can people have circular thoughts and deteriorating mental state? Sure. That's not a "feedback loop" between layers -- the chemicals are just doing their thing and the thoughts happen to be the resulting subjective experience of it.

To answer your question about the "thought trap". If "it's possible for simple normal trains of thought to latch your brain into a very undesirable state" then I'd say that means the mind/brain's self-regulation systems have failed, which would be a disorder or illness by definition.

Is it always a structural or chemical problem? Let's say thinking about a past traumatic event gives you a panic attack... We call that PTSD. You could say PTSD is expected primate behavior, or you could say it's a malfunction of the management systems. Or you could say it's not a malfunction but that the 'traumatic event' did in fact physically traumatize the brain that was forced to experience it...

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AstralStorm 5 days ago | parent [-]

Sure the thoughts can influence your chemical state. Scott even provides an example. Suppose you become so engrossed in your weird idea you start to lose sleep over it... Or start to feel anxious about it.

At some point, your induced stress will cause relevant biological changes. Not necessarily directly.

PTSD indeed is likely an overload of a normal learning and stress mechanism.

	▲	anon84873628 5 days ago \| parent \| next [-]
		The core thing is, am I really in control of my brain, at a fundamental level? If my thoughts are the result of electrochemical reactions, which everywhere else in the universe follow normal deterministic (even if stochastic) physics... How does thinking actually change their result? The unsettling conclusion is that it doesn't. The thoughts are the result of the reactions continuously in progress, and any sensation that we are a actively making decisions and guiding the process is simply an illusion created by that very same process. I.e. there is no free well. Under that view, the bipolar feedback loop example disappears. The engrossing or psychotic thoughts are not driving the chemistry, they are the chemistry. The whole thing is just a more macro view where you see certain oscillations play out. If the system ultimately damps itself and that "feels like" self control, it was actually a property built into the system from the start.
	▲	snapcaster a day ago \| parent \| prev [-]
		It's chemicals all the way down