Supplementary motor area (SMA)

Clinic

• SMA is a part of motor cortex that contributes to the control of movement.
• It is located on the midline surface of the hemisphere just in front of (anterior to) the primary motor cortex leg representation.
• Neurons in the SMA project directly to the spinal cord and may play a role in the direct control of movement.

Function

Possible functions attributed to the SMA include the

• Postural stabilization of the body
• Coordination of both sides of the body such as during bimanual action
• Control of movements that are internally generated rather than triggered by sensory events
• Control of sequences of movements