PTP: that's a great question. It seems that most kids are "hard wired" in terms of sensory processing - meaning it's just the way we are. But lately I've been wondering if the whole theory of neurotoxins and autism applies to SPD as well. Just my intellectual queries....so much to ponder.
In terms of SPD, Jean Ayres theorized that in the absence of any frank neurological pathology the central nervous system was just hard wired differently when sensory integrative dysfunction was present. The thing is though that she also theorized that disruptions in sensory integration were also part of the problems that resulted in learning disabilities. Your question about the drive for sedentary activities is certainly appropriate, as it takes participation in movement activities to stimulate the vestibular system and facilitate the sensory integrative process. I think its a question for more research...the chicken or the egg?
