Final answer:
Functional magnetic resonance imaging (fMRI) measures changes in blood flow and oxygen consumption in the brain to map brain activity, revealing which regions are responsible for specific functions like thought and motor control.
Step-by-step explanation:
The technique being described is functional magnetic resonance imaging, or fMRI. This advanced imaging technology allows for the mapping of brain function, as it can detect changes in blood flow and oxygen consumption within the brain during different activites. The increase in oxygen consumption by nerve cells during activity results in different magnetic properties of blood hemoglobin, which the fMRI can measure to generate images reflecting brain activation.
Other medical uses of magnetic fields include measurements such as the magnetocardiogram (MCG) for the heart and magnetoencephalogram (MEG) for the brain, which are less commonly used due to the difficulties in measuring such faint magnetic fields. However, advances in measurement instruments like the Superconducting Quantum Interference Device (SQUID) have made it possible to measure very small magnetic fields at liquid helium temperatures.