Functional Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) is the most important imaging advance since Conrad Röntgen introduced x-rays in 1895. Although researchers have long appreciated the unparalleled importance of MRI in diagnostic medicine, the emergence in the early 1990s of functional MRI (fMRI) - which measures hemodynamic changes after enhanced neural activity - had a real impact on basic cognitive neuroscience research. fMRI was developed on the basis of a series of phenomena discovered beginning in the late nineteenth century, including the tight coupLing between neuronal activity and brain-blood flow, the distinct magnetic property between oxygenated and deoxygenated hemoglobin, and the flow-metaboLism uncoupLing under neuronal activation. This article reviews the historical events that led to the discovery of fMRI, basic principles of fMRI mapping, and appLications. We also discuss Limitations of fMRI, including the pitfall of interpreting data and future directions.