In article ,
Martin wrote:

If you can find somebody with no vestibular (semi-circular
canal) function, who can walk about without falling over using only
his sense of touch I will be a little surprised.

Then prepare to be surprised. I am just one such - but, then, I
am lucky because I have had a lifetime to adapt.

I can even ride a bicycle and ski, but I need a very stable one
of the former, and it took me 150 hours to learn the latter where
people with normal abilities take 30.

I have had recurring vestibular (semi-circularcanal) function
problems. I couldn't stay standing up without leaning against
something or holding on to something. You must be almost unique.

That is normal - I may be a bit unusual, but I am by no means
unique. There are a fair number of people around who have had
none since birth and you won't notice - many of those will be
profoundly deaf, too, of course. I have heard about someone who
lost his vestibular function in old age (20s) and adapted as well
as I have - now that IS rare!

I almost certainly lost the function after I had learned to walk
and while still very young, so I could still develop new neural
pathways (both for balance and hearing), which is why I am lucky.
But using both all day is very, very (physically) tiring - I can
carry a 50 lb pack all day over Scottish hills and be less tired
than after a day of interacting with people.


Regards,
Nick Maclaren.