What is a reason why poisoning can cause dizziness and vomiting related to the vestibular system?

• A. Poisons target the cochlea causing hearing loss
• B. Poisons target the vestibular system, triggering nausea and vomiting
• C. Poisons disrupt the retina
• D. Poisons affect the somatosensory cortex

Answer: (B)

The reason poisoning can cause dizziness and vomiting is that toxins can directly affect the vestibular apparatus in the inner ear—the semicircular canals and otolith organs—or the vestibular nerve. When these structures are disrupted, they send abnormal signals about head motion and position to the brain. The brain then experiences a mismatch between what the body feels and what the eyes see, which can activate autonomic centers in the brainstem, including those involved in nausea and vomiting. This vestibular-autonomic interaction explains why dizziness and vomiting occur with vestibular system involvement. In contrast, affecting the cochlea would mainly alter hearing, the retina would affect vision, and the somatosensory cortex would alter touch or proprioception, not produce the same vestibular-induced nausea.