What effect does motion sickness typically have on a person?

Motion sickness is characterized primarily by feelings of nausea and discomfort. This condition occurs when there is a disconnect between what a person's eyes see and what their inner ears (which help control balance) sense. For instance, during travel, the eyes may perceive motion from the environment, while the inner ear may not detect a corresponding physical movement if the person is seated in a vehicle. This discrepancy sends mixed signals to the brain, resulting in symptoms such as nausea, dizziness, and general discomfort.

The other outcomes listed do not typically align with the effects of motion sickness. While dehydration can occur if someone becomes nauseous and vomits, it is not a direct effect or symptom of motion sickness itself. Increased appetite is contrary to the discomfort that a person experiences while feeling nauseous, and sensory overload is more related to excessive stimulation of the senses rather than the specific symptomatology of motion sickness. Hence, the correct answer reflects the most common and direct experience resulting from motion sickness.