A curious consensus: "brain scans prove disease"?

Presumably in recognition of the fact that there is no chemical test that can be used to diagnose any of the alleged mental illnesses, journalists and medical opinion leaders have proclaimed that brain scans--particularly, functional imaging studies--can be used to confirm the presence of psychiatric disease. Although the scientific record contradicts these assertions, the news media have ignored a critical evaluation of what, exactly, the new technologies purport to explain. The article that follows presents a critical analysis of the theoretical, practical, and philosophical limitations of the functional neuroimaging modalities (fMRI, PET, SPECT), and why these methods are not used outside of the research setting in the clinical practice of psychiatry today.