Nausea is not a sickness, it’s more a symptom of several conditions, many of which are not related to the stomach. Nausea is often indicative of an underlying condition elsewhere in the body.
As an example, some people get travel sickness, which is caused by confusion between perceived movement and actual movement.
Here, our sense of physical equilibrium comes by the inner ear working together with eyesight. When these two don’t “agree” as to how the body is actually moving, we feel sick even though the stomach itself has nothing to do with the situation.
By the same token, when someone is having a panic attack or even during bouts of anxiety, how they see their situation probably won’t agree with how they feel about it, which again leads to a sense of confusion.
Butterflies in the stomach is a less severe example.
The stomach gets involved because the brain is reasoning that one of the senses is hallucinating, perhaps due to eating something bad. The brain then induces vomiting to clear that out .
