fMRI stands for Functional Magnetic Resonance Imaging, which is a technique used to view activity inside the body. More specifically, fMRI measures blood flow in different parts of the body, and tracks changes in the blood flow in order to make inferences about what is going on during the imaging period.
In psychological research, the fMRI machine tracks changes in blood flow in the brain during the course of the experiment. When a brain area begins to show evidence of increased blood flow, it generally means that particular area is more active. By matching the type of mental activity being engaged in with the area of increased blood flow, psychologists are able to learn which areas of the brain are responsible for different mental processes.
How Does It Work?
As the neurons in the brain become more active, they begin to increase the amount of glucose and oxygen they call for from other parts of the body. Red blood cells have a small but measurable natural magnetic resonance that changes depending on whether the cell is currently holding oxygen or not. The change in resonance as the cells deliver oxygen to the more active neurons results in a contrast that is displayed in the fMRI images. The result is a completely noninvasive process that allows for precise imaging of brain activity over a very precise window of time.
Is It Safe?
fMRI is considered to be a very safe technique. Imaging is completely noninvasive, and requires no medications to work. The only significant contraindications for the procedure are ferromagnetic implants in the participant. Because the fMRI machine generates a very powerful electrical field, any kind of medical implant that is attracted to a magnet prevents a person from participating in an fMRI study. If you're interested in the study, the Barnard Toddler Center Study team can give you more specific information and answer any questions you may have.