Hi,
I hate to be the one to mention it but there are a couple of possible reasons for neurological symptoms like those you describe.
IBD is the most commonly mentioned cause but I strongly suspect it is not one of the most common causes.
It's natural (or at least expected ) in the spider morph.
It's a known symptom of overheating.
It can be caused by parasites. Some kind of nematode if memory serves.
It can also be caused by the chemicals used to treat for mites.
dr del