magnétotoencéphalographie

Magnetoencephalography, often abbreviated as MEG, is a non-invasive neuroimaging technique that measures the magnetic fields produced by electrical activity in the brain. These magnetic fields are extremely weak and are detected by highly sensitive devices called magnetometers, typically superconducting quantum interference devices (SQUIDs). MEG offers excellent temporal resolution, on the order of milliseconds, allowing researchers to observe the brain's activity as it happens. Its spatial resolution is also good, though generally not as precise as techniques like fMRI.

The electrical currents generated by neurons in the brain produce associated magnetic fields that extend outside the head. MEG sensors are strategically placed around the head to capture these faint magnetic signals. By analyzing the strength and location of these magnetic fields, scientists can infer the patterns of neural activity. MEG is particularly sensitive to activity in the cerebral cortex, the outer layer of the brain.

MEG has applications in both basic neuroscience research and clinical settings. It can be used to study various brain functions, including language processing, sensory perception, and motor control. In clinical practice, MEG is employed for pre-surgical mapping of brain areas related to epilepsy, allowing surgeons to identify and avoid critical functional regions. It can also aid in the diagnosis and understanding of other neurological disorders. The technique does not involve radiation and is generally considered safe for participants.