Motion sickness

A quote:

When feeling motion but not seeing it (for example, in a ship with no windows), the inner ear transmits to the brain that it senses motion, but the eyes tell the brain that everything is still. As a result of the discordance, the brain will come to the conclusion that one of them is hallucinating and further conclude that the hallucination is due to poison ingestion. The brain responds by inducing vomiting, to clear the supposed toxin.

So your brain decides you're hallucinating and then just leaps to the conclusion that it's because of poison? And then makes you throw up? Man, your brain is either a jerk or it just decides on a course of action without much thought.

Motion sickness