Evaluation of the effects of cerebrospinal fluid on functional MRI signals

Multi-echo echo-planar imaging（Multi-echo EPI）is a magnetic resonance imaging（MRI）sequence allowing MRI images recording at different echo times after excitation. Its application to functional MRI（fMRI）studies has enable the acquisition of new neuronal information compared with the classical single-echo EPI. For instance, in a previous study we could monitor microscopic neuronal changes originating from population differences. However, the neuronal information acquired by multi-echo EPI is subjected to artifacts caused by partial volume effect in the boundary regions between the neuronal tissues and other compartments such as the cerebrospinal fluid（CSF）. This report shows that CSF affected many fMRI image voxels in the brain.