Final answer:
The supplemental motor area and premotor cortex, which are secondary motor cortices located adjacent to the primary motor cortex, are activated when preparing to execute a limb movement. They are responsible for planning and coordinating movements before execution by the primary motor cortex.
Step-by-step explanation:
The area activated when a participant is preparing to execute a limb movement is known as the supplemental motor area (SMA). This area works closely with the premotor cortex, both of which are secondary motor cortices located adjacent to the primary motor cortex. The premotor cortex aids in controlling the movements of core muscles for posture, while the SMA is critical for planning and coordinating sequential movements based on prior experiences, such as those necessary to drive a car in anticipation of a traffic light changing.The primary motor cortex is responsible for executing movements once they have been planned by these secondary motor cortices. The prefrontal cortex is involved in executive functions and initiates movements by projecting into these secondary motor areas.