Functional MRI: A phrenology for the 1990s?

These are my own words, and though I would stand by them, I may well live to regret writing them. Functional MRI is touted widely, by no means solely by this author, as a method to detect regional brain activation patterns on individuals, and it reasonable to expect that enthusiastic readers might take this rather literally. In fact, however, it is only in the rare case that the validity of single subject work has been tested critically (e.g., in presurgical mapping studies, or multiple subject studies with identical outcomes). Taken at face value, the claim for single subject sensitivity, the failure to replicate across individuals, or even across trials for single subjects, have all been interpreted in print as demonstrating “differences in processing strategy” or “learning effects.”