So through this method of inference -- and we're measuring blood flow, not neural activity -- we say that an area of the brain that's getting more blood was active during a particular task, and that's the crux of how fMRI works.
所以用这种手法来推理 我们测量血液的流动，不是神经的活动。 我们可以说大脑的某个部分得到了更多的血液， 这个部分在人做某些事情时特别活跃。 这就是功能磁共振成像的关键。