What is the motor cortex?
The motor cortex, as its name suggests, is pivotal in motor functions. It is part of the cerebral cortex. Early TMS research revealed that stimulating the motor cortex can cause the conduction of nerve impulses to the spinal cord. The motor cortex is currently used as a gauge to determine the appropriate strength of TMS pulses in a given subject. Researchers will stimulate the motor cortex and check for muscle movement. They will then note the setting required to induce this muscle movement, and use a lower setting (sub-motor threshold) to stimulate other parts of the brain as required by the study/treatment protocol. This is an important safety practice which greatly reduces the risk of seizures. References: [1] Marcello Massimini, Fabio Ferrarelli, Steve K. Esser, Brady A. Riedner, Reto Huber, Michael Murphy, Michael J. Peterson, Giulio Tononi. (2007) Triggering sleep slow waves by transcranial magnetic stimulation. Proceedings of the National Academy of Sciences of the United States
