Functional magnetic resonance imaging (fMRI) is fast becoming the method of choice in
the field of neuroscience. The ability to interrogate the whole brain with high spatial
resolution with a number of different presentation types has been useful in understanding
how the brain functions. Moreover, the non-invasive nature of MRI allows longitudinal
studies to occur in normal and patient populations to understand the effects of
development or the disease process. Recent advances in data analysis (voxel based
morphometry) have also been developed to investigate volumetric changes in the same
populations.
In fMRI, the coupling between neural activity and blood flow has been exploited to
produce activation maps. The neuronal activation signal is detected by the blood
oxygenation level dependent (BOLD) signal changes that correlate with the paradigm
presented to the subject. Issues related to the physiology of the BOLD signal and how it
impacts the field of fMRI will be discussed. Furthermore, the details of the fMRI
experiment will be reviewed as fMRI is moving from the research stage to clinical
application.
This lecture will provide an overview of the physiologic origins of the functional imaging
signal, acquisition methods, paradigm design issues, and post-processing methods used to
generate the activation maps.
Educational Objectives:
1. Understand the origin of the MR based signal used for fMRI
2. Understand the issues related to an fMRI experiment including design, acquisition
and processing
3. Understand the issues related to clinical application of fMRI