For non-techies:
http://ideas.ted.com/much-of-what-we-kn ... with-fmri/
For the techies:
http://www.pnas.org/content/113/28/7900.full.pdf
Functional MRI (fMRI) is 25 years old, yet surprisingly its most
common statistical methods have not been validated using real
data. Here, we used resting-state fMRI data from 499 healthy
controls to conduct 3 million task group analyses. Using this null
data with different experimental designs, we estimate the incidence
of significant results. In theory, we should find 5% false
positives (for a significance threshold of 5%), but instead we found
that the most common software packages for fMRI analysis (SPM,
FSL, AFNI) can result in false-positive rates of up to 70%. These
results question the validity of a number of fMRI studies and may
have a large impact on the interpretation of weakly significant
neuroimaging results.
