Originally published on Nov. 12, 2017.


This article will be looking at the touch processing system in a bit of detail. If you're anything like me, you like to know why something works before you'll do it. So this introduction to the touch system will give the background to future articles that will talk a bit more about practical strategies to support your child with difficulties with touch (tactile) processing.

I think that knowing a bit about how the brain processes touch helps Families to be more independent of their Professionals in choosing the right strategies for them. With the right knowledge, you'll understand why a strategy might work, and how to adapt it.

Your tactile system has receptors that take in touch information through the skin. It's the largest sensory system in the body, and so if you have difficulty with processing touch, it has the potential to effect lots of different areas of development. I'm going to mainly talk about children who have emotional over-reactions to touch (and therefore food too).

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The touch system has two branches, the discriminative and the protective parts.

The discriminative system helps us with precision information. We need it to explore our food and toys, and develop good manipulation skills with our hands for things like writing, turning the pages of a book, or doing a puzzle.

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The discriminative system carries a few different types of information, that you might not think of as being part of the touch system:

  • Discriminative info like texture
  • Deep touch pressure
  • Vibration
  • Proprioception (more about this in another post)

The protective system is designed to keep us safe on a much more basic level. It is the system that will make you jump when an insect lands on you, make you shiver when there is a sudden cold draught, or think about running away if someone brushes against you in a dark alley.

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The protective system carries information about a few things too:

  • Light touch
  • Pain
  • Temperature

The protective system, unlike the discriminative system, sends branches out to the parts of the brain that make us switch focus and be alert, and react by running away, putting up a fight, or freezing. All useful things in the right situation.

But sometimes children (and adults) have an overactive protective system, and/or an underactive discriminative system. So they are triggering strong protective behaviours in response to touch sensations that would not bother the rest of us. For example, getting food onto their hands or into their mouth can trigger genuine fear and anxiety. Eating foods of a certain temperature might be an issue.

Luckily for us, our brain isn't very good at processing information from both parts of the tactile system at the same time. If you want to see this in action, then next time you bang a knee (generating a pain signal, processed in the protective system), then rub it (deep pressure, processed in the discriminative system), and it won't hurt so much.

We can use this trick of fate in therapy activities and strategies for your child by:

  • Supporting their discriminative skills in our choice of activity
  • Using deep touch pressure such as massage
  • Using toys that vibrate (but not if they only have light vibration or the brain thinks it is light touch)
  • Doing activities that get us moving our muscles (proprioception)

So, we might build more opportunities to use the discriminative pathway into a child's day, and especially before we ask them to push themselves to do something difficult in their feeding, like messy play.

Have you got any examples of touch activities that your child finds difficult? Maybe they make more sense now that you know more about the way the brain processes touch? As usual, post your comments and questions!

Posts from Find the Key Speech Therapy are intended for information. They are not intended to, and cannot take the place of advice from an appropriately qualified Speech and Language Therapist who knows your child. Find the Key Speech Therapy does not take responsibility for the use of any advice without appropriate professional guidance.