Which situation is likely to lead to caloric vertigo?

Caloric vertigo is a condition that can occur when there is a sudden change in the temperature of the inner ear, which can affect balance and equilibrium. Rapid descent while diving is particularly relevant in this context because the quick change in pressure and the possible accompanying temperature effects on the inner ear can disrupt normal vestibular function.

When a diver descends rapidly, the pressure changes can dramatically impact the gas exchange in the body and blood flow, which may lead to symptoms of vertigo as the body struggles to adjust to the new environmental conditions. The inner ear, where balance is regulated, can be highly sensitive to such abrupt changes, resulting in a miscommunication about body orientation and leading to symptoms of disorientation or vertigo.

Other situations like prolonged diving at depth, exiting a hot sauna, or changing altitude while flying involve more gradual adjustments to environmental conditions or effects that do not typically provoke the same immediate and intense sensory conflict that is seen with rapid descent. Hence, the scenario of a rapid descent while diving is the most likely to trigger caloric vertigo due to the direct impact on the vestibular system.