Pyramid (brainstem)

Pyramid (brainstem)

The Pyramid (brainstem) or Pyramidal tract is a crucial part of the brainstem that plays a significant role in the human nervous system. It is a white matter pathway responsible for carrying motor commands from the cerebral cortex to the spinal cord and then to the muscles.

Structure

The pyramid is located in the medulla oblongata, the lower half of the brainstem. It is a bilateral, elongated mound that is visible on the anterior surface of the medulla. The pyramid contains the corticospinal tract, a collection of axons that originate in the cerebral cortex and descend through the brainstem and spinal cord.

Function

The primary function of the pyramid is to transmit motor impulses from the brain to the spinal cord. These impulses are then relayed to the muscles, controlling voluntary movements. The pyramid is particularly important for fine, skilled movements, such as those required for writing or playing a musical instrument.

Clinical significance

Damage to the pyramid or the corticospinal tract can result in a range of motor deficits, known as pyramidal syndrome. Symptoms can include muscle weakness, increased muscle tone, and decreased fine motor control. In severe cases, paralysis may occur.

See also

• Brainstem
• Corticospinal tract
• Medulla oblongata
• Pyramidal syndrome