The Center for Neuromagnetism
The Center for Neuromagnetism at the Department of Physiology and Neuroscience, New York University School of Medicine performs noninvasive functional brain imaging using magnetoencephalography (MEG). When MEG information is combined with structural imaging such as MRI, it is called magnetic source imaging (MSI).
This is a technique that measures the very small magnetic fields produced by brain activity with uniquely high spatial and temporal resolution. Our research encompases both basic and clinical studies. We are interested in examining the spatial and temporal underpinnings of brain function during cognitive processes in different functional states (for example; sleeping, listening, watching a movie, relaxed with the eyes closed or open).
Several functional imaging techniques are now available which provide the possibility to study human brain function from the outside. MEG is one such functional brain imaging technique, which is truly non-invasive and allows the localization of the electrical activity of nerve cells within the brain with a few mm accuracy and fast time resolution (~1 msec).
During the MEG recording, the person is sitting in a chair and the MEG system is placed close to your head. The MEG system is located in a magnetically shielded room and consists of a Dewar filled with liquid helium, containing detection coils and superconducting electronics.
The magnetic field generated by intracellular currents from an individual neuron is extremely small, too small to be detected outside the head. In fact, several thousand synchronously active neurons are needed to generate the field measured by the MEG. The magnetic fields being measured from the brain are in the range of 50-1000 femtotelsa (fT), which is an extremely weak signal and is about one billion times smaller than the earth's magnetic field. The MEG technique has very sophisticated instrumentation sensitive enough to detect these weak signals, while simultaneously discriminating against interference from strong signals that come from the environment.