Motor cortex

The motor cortex comprises interconnected fields on the posterior frontal lobe—chiefly Brodmann area 4 (primary motor cortex, M1) and area 6 (premotor cortex and supplementary motor areas)—that plan, select and execute voluntary movements. These regions transform goals into patterned activity in descending pathways to brainstem and spinal motor circuits, enabling dexterous eye, face and limb actions. Modern work shows overlapping, action‑type representations rather than a strictly point‑to‑point "homunculus," and highlights direct cortico‑motoneuronal projections that underwrite fine finger control. Clinically, motor‑cortical organization shapes deficits after stroke and neurodegenerative disease and guides mapping for neurosurgery and neurotechnology.