Final answer:
The motor tract responsible for ipsilateral gross postural adjustments subsequent to head movements is the vestibulospinal tract.
Step-by-step explanation:
The motor tract responsible for ipsilateral gross postural adjustments subsequent to head movements, facilitating activity of the extensor muscles and inhibiting the activity of the flexor muscles, is the vestibulospinal tract. This tract connects the brain stem nuclei of the vestibular system with the spinal cord, allowing posture, movement, and balance to be modulated based on equilibrium information provided by the vestibular system. The vestibulospinal tract plays a crucial role in maintaining balance and coordinating postural muscles.