Your friend Frank had a stroke in the ventral area of his spinal cord. What tract could be affected, and what might he have difficulty with after his stroke? (There are 2 correct answers. Each correct answer is worth 0.75 points) Select 2 correct answer(s) Question 19 options: A) Vestibulospinal tract B) Corticobulbar tract C) Corticospinal tract D) Balance E) Voluntary motor movements
The correct answer and explanation is:
Correct Answers:
- C) Corticospinal tract
- E) Voluntary motor movements
Explanation (300 words):
The ventral (anterior) area of the spinal cord plays a critical role in transmitting motor signals from the brain to the body. One of the primary tracts located in this region is the corticospinal tract, particularly the anterior corticospinal tract, which is involved in voluntary motor control, especially of axial (trunk) muscles.
The corticospinal tract originates in the motor cortex of the brain and travels down through the brainstem and spinal cord. It has two main divisions:
- The lateral corticospinal tract (located more dorsally), which controls limb movements.
- The anterior (ventral) corticospinal tract, which influences posture and movement of the trunk.
A stroke affecting the ventral spinal cord would likely damage the anterior corticospinal tract. As a result, Frank would have difficulty with voluntary motor movements, especially involving the trunk and proximal muscles. This may manifest as weakness or paralysis in certain muscle groups, difficulty sitting or standing upright, and problems with coordinated motor tasks.
Let’s consider the other options:
- A) Vestibulospinal tract: This tract is involved in balance and posture, but it is located more laterally in the spinal cord and is not directly in the ventral area.
- B) Corticobulbar tract: This tract carries motor signals from the cortex to the cranial nerves in the brainstem, not the spinal cord, so a spinal stroke wouldn’t affect it.
- D) Balance: While balance can be indirectly affected by motor impairment, it is primarily regulated by the vestibular system, cerebellum, and vestibulospinal tracts.
Thus, the most accurate answers are:
- C) Corticospinal tract – affected by a ventral spinal cord stroke.
- E) Voluntary motor movements – function impaired due to corticospinal tract damage.