Sensory processing happens when the nervous system collects data from sensory experiences and organizes it so that the brain can make an appropriate response. For instance, your eyes register obstacles in your path as you move, and then while communicating with your brain, messages are sent to your feet to alter your path so that you can navigate around the pile of books on the floor.
The disorder means that information is not processed appropriately, or you may have a delayed response, resulting in an over- or under-reaction, depending on the stimuli. Going with the same walking example, I had trouble navigating around obstacles because these messages to change direction were not delivered in a timely manner. I bumped into a lot of things, including hitting the wall when trying to enter a doorway. This problem is called dyspraxia, affecting your ability to motor plan. (NOTE: Don’t ask me where that name came from. What a bizarre word!)
Another aspect of sensory processing is called sensory modulation. Touch, sound, smell, etc can register as more invasive or distracting than normal. I had trouble with touch. I didn’t like to be held. These basic experiences registered as threatening for some reason. They didn’t provide the usual, expected comfort. Being held or touched on the arm unexpectedly caused internal alarm, instead of acceptable human contact.
The best way I can illustrate this is with the common social phenomenon known as “elbowing.” You’re telling a joke or sharing a story and, to add emphasis, you nudge someone in the side or on the arm with your elbow. “Right? Wasn’t that hilarious?” Nudge, nudge.
I assume for most people, this touch registers as human contact. Someone is including me in the conversation in a personal way.
For me, it means my whole body now stands at high alert. It’s an invasion of personal space. Even if I know the person means no harm, my body reacts like it’s under attack. And internally, I’m becoming more and more agitated.
My body is clearly over-reacting to the stimulus. But that’s my natural reaction. And it requires training to improve that proper response. Generally speaking, as an adult it has gotten easier to calmly work through the uninitiated contact, to not have an internal reaction of aggravation and irritation. But there are still moments when other factors have been working on my nerves for a while and the elbowing just sets me over the edge.
As a child, though, I would lash out in anger. I knew this touch bothered me but I didn’t understand why. And so it was very confusing for those around me to have me over-react in extreme ways to something that seemed so innocent.
There are many nuances to sensory processing disorder, as seen in this checklist of potential symptoms. Each child has a unique combination of sensitivities. For me, my problem areas were dyspraxia and sensory modulation (multiple problems, but especially touch and sound).