That's starting to get into paralinguistic territory. Sneeze sounds, for example, are learned to a degree (think some people sneezing very quietly or very loudl

That's starting to get into paralinguistic territory. Sneeze sounds, for example, are learned to a degree (think some people sneezing very quietly or very loudly), and can be relearned even though they are involuntary in their timing, unlike "real" words.