There is no doubt that the brain and the body are entwined. I guess that a more explicit title would be: you are implemented on kludgy and limited wetware (a human brain) which is influenced by a myriad of factors, most of which you are unaware of.

Your body does influence you, but then so do a lot of other things. If I changed it to you are implemented on a human body, then someone else will say: "hey, what about the microbes, bacteria and organisms that live in my gut and on my skin". I would then need to acquiesce and add this in. Then, someone will say: "hey, what about social influences". I would then need to add this in. Hopefully, you get the idea that this could potentially go on for a very long time.

I think that you are implemented on a human brain is the best way to convey the ideas in the post.

Would love to see some LW heavy weights weigh in on this topic

Same. I guess it comes down to how much of the causal chain you want to consider. I am happy just considering the brain, but of course there are many other things that influence the neural patterns that get activated in the brain.