ABSTRACT
Functional magnetic resonance imaging (fMRI) is a neuroimaging procedure performed in the MRI scanner to evaluate functional brain activity, basically by detecting changes associated with blood flow during specific stimuli. fMRI is increasingly used in clinical practice, although it started mainly in the research world, where it was used to map brain activity evoked from certain stimuli or tasks in healthy individuals. Although well established, fMRI is still in its infancy. fMRI is completely non-invasive, stress-free for the patient and most importantly it can be obtained preoperatively allowing for a well-designed pre-surgical planning. Blood oxygenation level dependent (BOLD) imaging is the standard method used in functional MRI (fMRI) studies, and relies on the content of diamagnetic deoxyhemoglobin in the blood to delineate neural activity. Historically, blocked designs were mainly adapted in fMRI from positron emission tomography (PET) studies. Event-related designs are advantageous compared to block designs, especially regarding the ability to avoid cognitive adaptation.
