6 ms·

>FMRI only measures blood flow Isn't it more like a measure of metabolic activity?

• foobarbecue 4y ago
  Indirectly. The idea is that when cell metabolic rate increases, the brain's circulatory system compensates by dilating vessels to increase flow to that area. (EDIT: this is wrong, see below)
  • thfuran 4y ago
    But the fmri is measuring change in decay time caused by change in blood oxygenation rather than change in flow rate, right? And that's a relatively direct measure of local metabolic activity (at least for some metabolic pathways).
    • foobarbecue 4y ago
      You're right, and I didn't know that. Thanks for educating me. Apparently it's called BOLD-contrast imaging. Time for me to go read about haemodynamic response since I didn't know that was a thing.