Medial vestibular function contributes to stabilization of which regions and coordinates what?

• A. Postural leg muscles; coordinates arm movements
• B. Visual field stabilization; coordinates neck and shoulders
• C. Bilateral stabilization of head, neck, and upper back; coordinates head and eyes
• D. Auditory processing; coordinates eye movements

Answer: (C)

Medial vestibular function is focused on keeping the head steady and linking head movement with gaze. Signals from the head’s rotation travel to the medial vestibular nucleus and then down the medial vestibulospinal tract to the cervical spinal cord. This bilateral projection activates neck (and nearby upper back) muscles on both sides, helping to stabilize the head and upper trunk as you move. At the same time, these pathways support the vestibulo-ocular reflex, so the eyes move in the opposite direction to head movement to keep the visual field stable.

So, stabilizing the head, neck, and upper back on both sides and coordinating head with eye movements fits best. The other options don’t match this role: one emphasizes leg posture and arm movements (a different vestibulospinal influence), another misstates the target regions, and another points to auditory processing, which isn’t a primary vestibular function.