Magnet resonance imaging (MRI) is based on the absorption and emission of energy in the radio frequency band of the electromagnetic spectrum. The information about the spins alignment and realignment to the magnetic field as well as the precession frequency of spins is reconstructed using the 3D-Fourier transform system. The optimal use of time processing to the spins realignment and dephasing enables us to visualize the contrast of various tissues in the anatomical structures of the human brain.
Unlike MRI, functional MRI delivers the functional information about brain activities during cognitive processing. fMRI is based on the "Blood Oxygen Level Dependent (BOLD) contrast" emerged from two effects: a) physiological effect (i.e. hemodynamics) and b) physical effect (i.e. magnetic susceptibility). On the basis of BOLD contrast, we can substrate the neural activities correlated to the specific cognitive processing we are interested in from the brain activities during the resting state.
This talk will give a short overview of the basic principles of MRI/fMRI methods.