A friend of mine recently asked me a simple question that I couldn't answer:
i want to know if there is a physiological explanation for why we have an easier time remembering things that we perceive to be true.bad example: suppose that you believed that the earth was flat. then i took you out into space and showed you that it was round. you would not forget that. i'm having a hard time expressing this very simple thought: we are constantly replacing old beliefs with new ones that are in some sense "more true". you can intuitively distinguish between those thoughts that you have that you think are true, and those that you think are false. it's a feeling. my question is if there is a physiological explanation. a "true" marker that your brain can put on memories, or a filing cabinet in your brain that is reserved for "true facts".
i don't care whether any facts are ever actually true or not. that's not the question. the question is how your brain sifts out the things YOU THINK are true from the things you think are false.
I did a quick pubmed search for "truth" and "fMRI" and came back empty handed. On the one hand, you might expect the brain to have a neural pathway dedicated to ideas that are perceived as statements of truth. Such a pathway might allow the cortex to privilege such truths over less trustworthy ideas. But the truth doesn't seem to have a distinct neural correlate. This strikes me as a little odd, considering that we have mental modules designed to detect lots of other things, like happy faces, acts of agency and cheaters. But I guess the brain wasn't designed with epistemology in mind. Being able to recognize the truth isn't that useful, at least from an evolutionary perspective.
But what about an even more elementary distinction, like being able to tell the difference between statements of fact (a proxy for truth) and matters of subjective opinion? Again, the brain doesn't seem to care. Your limbic system can instantly tell which statements come with an emotional component - and I guess opinions tend to be more emotional than uncontested facts - but that hardly counts as a "physiological marker of truth".
So does this mean that our evolved brain doesn't care about the truth? Is the mind just a pragmatic machine, only interested in what works? How else could experiments even look for the neural correlates of truth?






Comments (11)
this seems like an empirical question even though truth might be subjective. I'm surprised there are no publications on this.
Posted by: steve | March 8, 2007 11:01 AM