CEREBELLAR HYPOPLASIA (Probable)

When we first got Aisling, she had such a pronounced head tilt that she had difficulty eating.  This, plus some balance problems, led us to suspect she had a severe ear infection.  Her first trip to the vet disproved that theory, however.  We now believe her symptoms are most likely caused by a condition called cerebellar hypoplasia, in which the cerebellum (the part of the brain that controls motion) is under-developed.  The condition is often seen in kittens whose mothers had panleukopenia (aka distemper) when they were pregnant.

Initially, we worried that she would not be able to lead a reasonably normal life, but as she got bigger and stronger, she learned to compensate.  What we had initially thought was a head tilt was actually tremors, and soon after she started getting enough to eat and gained strength, they improved somewhat.  In addition to the head tremors, she was a bit wobbly and tended to fall over when walking on uneven surfaces.  

Happily, as she grew older, she gained more and more control over her motor skills.  She still has some trouble balancing on uneven surfaces and the head tremors are evident when she's really concentrating on something or is nervous, but other than that, she's fairly normal.  She climbs well, but is unable to jump very high, probably due to balance issues.

I've learned that most kittens with cerebellar hypoplasia, though they may look hopeless at first, go on to lead full, happy lives.  Aisling certainly is.

After Aisling settled in and decided she wasn't going to be a feral cat anymore, she became very placid.  Nothing seemed to upset her:  not dogs barking, doors slamming, people shouting, or any other sudden, loud noise.  It struck me that she was a very sound sleeper, too, and I usually had to poke her to wake her up.

One afternoon as she was napping, it occurred to me that I should conduct an experiment.  I crept up near her, then clapped my hands loudly a few inches over her head.  No response.  I shouted her name.  No response.  In fact, nothing I did got any response until I petted her.  She was placid because she couldn't hear a thing.

We aren't sure if her deafness is somehow linked to the cerebellar hypoplasia, or if the deafness and the motor problems had some other cause, such as head trauma or exposure to some toxin.  We're fairly sure Dubh is her sibling, and he is perfectly normal.  I guess we'll never know for sure.

Aisling is the first deaf cat I've had.  I'm surprised she survived as long as she did in the "wild" before we found her, but as an indoor cat, deafness isn't a severe handicap for her.  I sometimes envy her ability to sleep through anything.

Oddly, she produces all the appropriate types of meows in the appropriate circumstances, though she is louder than most cats.  My guess is either the "meow tones" are genetically programmed rather than learned, or she lost her hearing at some point after she was born.  Again, we'll never know.