Neuroimages are playing a growing role in biomedical research, medicine, and courtrooms. Unfortunately, that often means they are used to bolster weak observational studies and imply correlation and causation. The people most likely to commit scientific sins with brain imaging, psychologists and neuroscientists, are least likely to acknowledge their acquisitions parameters and many other things that scientists know influence data and conclusions.

Brain scans are portrayed as science but they are little help at answering complex questions such as: 'What is depression?' or 'Is a defendant lying?' no matter what echo time, flip angle or repetition time is invoked. Neuroimaging technologies simply capture pictures as a person thinks, feels, and experiences sensations. The President says they will be indispensable to the BRAIN (Brain Research through Advancing Innovative Neurotechnologies) initiative launched by the federal government to advance understanding of the human brain and brain disorders. 

Maybe. Advocates weigh in. A new report on the topic consists of six essays: 

Neuroimaging: Beginning to Appreciate Its Complexities
Erik Parens and Josephine Johnston
While neuroimages are being used in courtrooms to help determine both guilt and sentencing, in marketing, and in the diagnosis of mental disorders, they are "readily open to misinterpretation, overinterpretation, and misapplication," write Parens and Johnston. They advise scientists, clinicians, lawyers, and others to be clear about how neuroimages are made and what they can—and cannot—do.

Functional Neuroimaging: Technical, Logical, and Social Perspectives
Geoffrey K. Aguirre
With new, powerful analytic techniques, there has been a shift in goals, from trying to understand the neural basis of a particular emotional or mental state to trying to predict behavior. But there are limits to the information that neuroimaging can convey. Aguirre explains the many steps involved in transforming raw data into a finished brain image.

Brain Images, Babies, and Bath Water: Critiquing Critiques of Functional Neuroimaging Martha J. Farah says neuroimages have attracted a lot of criticism, such as that they do not show neural activity directly and that they are "too convincing." Farah takes on the criticisms and finds that in some cases they have been overextended in ways that are inaccurate or misleading. "None of the criticisms reviewed here constitute reasons to reject or even drastically curtail the use of neuroimaging," she concludes.

Neuroimaging and Psychiatry: The Long Road from Bench to Bedside Helen S. Mayberg
says neuroimaging has implications for psychiatric diagnosis, treatment, and risk assessment, but it is not ready for use in clinical psychiatry. Claims to the contrary "give false hope to patients and their families," writes Mayberg, who reached this conclusion after spending the last 20 years studying functional neuroimaging patterns in patients with depression. 

Seeing Responsibility: Can Neuroimaging Teach Us Anything about Moral and Legal Responsibility? David Wasserman and Josephine Johnston
say neuroimages that visualize a decision-making activity or its timing could alter our understanding of personal responsibility by challenging the notion of free will. Although neuroscience may point toward determinism, Wasserman and Johnston argue that the concepts of moral and legal responsi¬bility are likely to be modulated rather than discarded.

Living with the Ancient Puzzle Erik Parens
says neuroimaging can help explain how experiences arise in human beings but thinks that it cannot by itself let us understand what it means to be a human being.

Read Interpreting Neuroimages: An Introduction to the Technology and Its Limits at the Hastings Center Report.