From what I understand, sensory issues are seen in kids (and adults) when they are either under sensitive or over sensitive to different types of sensory stimuli...which then results in problems for them...
So it can be like the kid who doesn't 'sense' pressure accurately...so they can be too rough, without realising it...they throw the ball too hard...push into people without meaning to...
It can be the kid who doesn't sense "tactile" information accurately...so they may be overly sensitive to fabrics that are too wooly or too stiff...they like to have their socks always pulled up...they can't bear the feeling of a tag at the back of their t-shirt...or they can't bear a certain type of touch (they often prefer deep pressure touch to gentle caressing)...
The kid who has sensory overload with sounds...so things like vacuum cleaners or planes or sudden noises are very distressing for them...
Kids who don't know 'where their body is in space'...so if they close their eyes, they can't really 'sense' where their arms/legs are...so these kids are often very fidgety and restless, trying to get 'sensory feedback' from their wriggles and squirms...
Kids who are overly sensitive to textures in their mouth...so they struggle with certain textures (e.g. lumpy foods)...
It's often hard to pinpoint what is going on (that's why an assessment is really important)...these kids often look like they are being 'naughty' or misbehaving...but really they are struggling from sensory overload or sensory understimulation...they also look like they are not paying attention...but sometimes it's because they are paying so much attention to their sensory stuff (because it's overloading their little bodies), that they can't pay attention to other stuff...
It's certainly seen in diagnoses such as autism or aspergers...but can also be a disorder just on it's own...a bit like a child might have a speech problem...
Occupational Therapists are usually the professionals that deal with sensory issues with kids...but not all of them...they often need to have specialised training...alot of the therapy they do with kids is providing them with a 'sensory diet', helping them to 'desensitise' them to sensory information...but also helping parents to recognise the 'signs'...
Hope that makes sense...
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