Chapter 9

Self-assessment Questions

1. What is preprocessing? How is it distinct from experimental analysis?
2. What are phantoms?
3. Why is correction for time of acquisition within a TR important?
4. If you saw a fMRI activation map that was highly positively active along the edge of the right hemisphere, but highly negatively active along the edge of the left hemisphere, what would you conclude?
5. What can be done to help prevent head motion, in terms of designing the experiment and setting up the subject?
6. How should researchers interact with subjects to minimize head motion?
7. How do researchers correct for head motion?
8. What is bias field correction, and why is it important?
9. Why do researchers coregister images?
10. What benefits are provided by spatial normalization?
11. What circumstances cause problems for spatial normalization?
12. Why might spatial smoothing increase the SNR of fMRI data?
13. What is the multiple comparison problem? Why is this more of an issue for fMRI than for behavioral studies, for instance? What approaches have been developed to compensate for it?
14. What is temporal filtering? Under what circumstances would it be useful?