Interoception/viscerality: How do you measure it and its decline with age?

Interoception

Many autistic people/nerds have deficient interoception (ability to read their body’s signals/what their body is trying to tell them). That’s what some people say as “groundedness”.
But deficits in interoception are also a big reason why older people decline (and get into situations where they don’t self-correct initial damage).