Donatien: I think it has been in several neurological or medical dictionaries that the University of Cambridge does. However, in the last five years, it has crept over the mainstream. Autism Asperger Publishing Company in the US has a good book on it.
Snehal: what a good idea to have the antonym - many people have a relative or absolute lack of interoception. We could probably make it into an a- or dys- word as lots of neurological and nervous concepts are.
It's quite of an elegant word. Curious that is how we haven't added it yet.
Quite an informative word to express what is happening inside the body. And its antonym should be added as well.