Functional MRI: Finally, a Textbook for All of Us

Extract

Functional Magnetic Resonance Imaging, by Scott A. Huettel, Allen W. Song and Gregory McCarthy. 2004. Sunderland, MA: Sinauer Associates, Inc. 492 pp., $79.95.

Imaging the human brain at work was revolutionized by the discovery of functional magnetic resonance imaging (fMRI) in the early 1990s. Prior to this, functional brain mapping was limited to a handful of medical centers capable of conducting positron emission tomography (PET) scans of regional cerebral blood flow. With the discovery of the endogenous blood oxygen level dependent (BOLD) contrast method in 1992, fMRI “democratized” the field by expanding the number of medical centers capable of functional brain imaging. Today, over a thousand peer-reviewed fMRI articles are published each year, many in high profile scientific journals that receive additional attention by the popular press. This explosion of scientific research is relatively easy to understand: fMRI can be conducted on the majority of the 6,600 MRI scanners installed in the US alone, the technique is completely noninvasive since it does not require injection of MRI contrast agents or radiopharmaceuticals, and, as an added benefit, fMRI provides a unique combination of high spatial and temporal resolution. Not surprisingly, fMRI is the imaging technique of choice for mapping cognitive and emotional systems in the healthy brain. More recently, fMRI has been applied to clinical populations to identify the brain mechanisms governing recovery of function from stroke and head trauma, detect early brain changes in neurodegenerative conditions, and measure the effects of psychoactive medications on neurodevelopmental disorders, as examples. fMRI provides a complementary method for testing neuropsychological models of brain function derived from other methods (lesion, electrophysiology).