Brain Imaging & Analysis Center

Head motion is a major concern in fMRI. Everyone knows that preventing motion is important and too much motion is a problem. What is not clear is how much motion becomes too much motion? Using fScan to assess head motion in real-time results in motion time plots of image stability. If there is some motion I recommend using the scanner microphone during the scan to remind the subject to stay still. If you decide that there is too much motion (see below) you might be better off stopping the scan immediately and then talking to the subject and/or doing something to improve head immobilization or using a task that is less likely to cause motion.

Here are some examples of fScan image stability plots with different amounts of head motion: