Application of Functional MRI in the Field of Rehabilitation Medicine

Kim, Yun Hee

Abstract

The higher cognitive functions of human brain are hypothesized to be selectively distributed across large-scale neural networks interconnected cortical and subcortical areas. Recently, advances in functional imaging made it possible to visualize the brain areas activated by certain cognitive function in vivo. Out of several technologies currently available for brain activation study, functional magnetic resonance imaging (fMRI) is increasingly being used because of its superior time resolution and finer spatial resolution. The technique is non-invasive without radiation hazard, which allow to take repeated multiple scans within the same individual. The most common approach to fMRI of brain is the one using 'blood-oxygen level dependent (BOLD)' contrast, which based on the localized hemodynamic changes following neural activities in the certain areas of brain. With functional imaging techniques including fMRI, neural networks subserving for higher cognitive functions such as language, memory, attention, and visuospatial functions could be visualized. Neural substrates of human emotion and motivation behaviors also begin to be unveiled. Brain mapping with functional imaging is a very useful method for detecting eloquent areas in a neurosurgical setting to prevent the residual disabilities. One of the issues recently having attention in the field of functional imaging is the reorganization of neural network following brain injuries. Much research results using fMRI identified intra- and/or interhemispheric reorganization of neural networks accompanied with functional recovery after brain injury. Effects of learning and rehabilitation on the extent and pattern of neural reorganization was also delineated. fMRI will be a very useful tool for developing of various rehabilitation treatments, which promote successful functional recovery by maximizing the plasticity of brain.