Magnetoencephalography (MEG)

... An imaging technique that allows the magnetic fields of the brain to be detected and recorded.

Magnetoencephalography (MEG), also known as Magnetic Source Imaging (MSI) provides an image of the brain by recording magnetic fields over the surface of the head. These fields are generated by “electric currents” inside the brain, resulting from electrically charged ions flowing within each brain cell. By measuring these magnetic fields, scientists can accurately pinpoint the location of the cells that produce each field. In this way, they can identify zones of the brain that are producing abnormal signals. For example, MEG can be used to:

Identify brain zones that emit abnormal electric currents associated with epilepsy.
“See” the magnetic fields associated with sensory areas of the brain by stimulating the senses during MEG.
Pinpoint the magnetic fields associated with motor skills by asking a patient to move various parts of the body during MEG.
View the brain zones that control language by having a patient perform linguistic tasks during MEG.
Identify the brain zones associated with learning and memory by having a patient perform cognitive tasks during MEG.

The MEG Laboratory is located in Hermann Hospital, the teaching hospital of The University of Texas Health Science Center at Houston, and is operated by members of the university’s Department of Neurosurgery. The following projects are under way in the MEG Laboratory:

Identification of brain zones producing abnormal electric currents associated with epilepsy in patients who are candidates for epilepsy surgery, in collaboration with the university’s Department of Neurology

Pre-surgical mapping of electrical currents in the cerebral cortex (the portion of the brain that coordinates sensory and motor information) in patients who will undergo surgical removal of lesions adjacent to this area of the brain
Identification of areas of the brain associated with delays in cognitive functions, such as learning and memory.
Mapping of electrical currents generated during language and memory tasks, and determination of the hemispheres of the brain that are dominant for these functions in normal and abnormal individuals
Assessing how the brain recovers sensory, cognitive and language functions following brain injury or stroke.