Current trends and challenges in MRI acquisitions to investigate brain function

Abstract

Functional magnetic resonance imaging (fMRI) studies using the blood oxygenation level dependent (BOLD) response have become a widely used tool for noninvasive assessment of functional organization of the brain. Yet the technique is still fairly new, with many significant challenges remaining. Capitalizing on additional contrast mechanisms available with MRI, several other functional imaging techniques have been developed that potentially provide improved quantification or specificity of neuronal function. This article reviews the challenges and the current state of the art in MRI-based methods of imaging cognitive function. KeywordsFunctional MRI; Neuroimaging; Cerebral blood flow; Cerebral blood volume; BOLD; Cognitive neuroscience Functional MRI (fMRI) using the blood oxygenation-level dependent (BOLD) response is by far the most commonly employed method for noninvasive localization of activity in the brain in cognitive psychology investigations. The method is non-invasive, does not employ ionizing radiation, and generally produces reliable depictions of brain activity with reasonable spatial resolution and whole-brain coverage.fMRI seems to have arrived as an established, appealing method. However, it is in fact a relatively new, even primitive method with considerable upside potential as methods improve. BOLD and other fMRI methods are advancing fairly rapidly, and there is some sentiment that the standard BOLD method is virtually obsolete. Such evolution is typical of new technologies, though not commonly appreciated in the rapid embrace of fMRI in cognitive psychophysiology to date.

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