Locating the SMA
Dr. Rustin Berlow locates the SMA (supplementary Motor cortex) for TMS stimulation.
Dr. Rustin Berlow discusses how to locate the Supplementary Motor Cortex and the positioning of the coil.
Locating the supplementary motor cortex is relatively easy because it is approximately 45% of the distance from nasion to inion, approximately halfway between DMPFC and the motor cortex, so SMA is the cortex on either side of the midline, also known as Brodmann’s area 6. Most simulations of the SMA are inhibitory and one can go just off the midline at a 45-degree angle, like this (demonstrates positioning with the coil) and if it’s bilateral, the same thing on the other side.