Transcranial Magnetic Stimulation: An Introduction
Transcranial Magnetic Stimulation (TMS) is a non-invasive method of stimulating or inhibiting electrical activity in the brain. It involves a metal coil that is capable of generating magnetic fields, which is then placed on the scalp. The magnetic field can then induce electrical currents in the brain, either stimulating or inhibiting electrical activity for a short period of time.
Research uses for TMS
TMS is a wonderful tool in neuroscience research, since it allows the demonstration of causality. Most other methods, such as fMRI and EEG, can only demonstrate that activity in a certain brain region is associated with a certain task. With TMS, we can temporarily slow a region, and see direct effects of this manipulation.
In our lab, we usually perform image-guided TMS. In this case, we start by taking an MRI of the subjects brain. We can then use this image to guide where we apply the TMS, and therefore have better accuracy in applying TMS to the target region.