The Sixth Sense (and the Seventh and the Eighth): An Introduction to Sensory Processing and Neurodiversity

Most people are familiar with the five senses: smell, taste, vision, hearing and touch, however, I am usually met with surprise when I tell children who I am working with, and their parents, that we also have three more: proprioception, vestibular and interoception.

Sensory processing is our ability to take sensory information in, make sense of it in our brain, and then respond in a way that is appropriate to the environment. For example, we use our vision to see an object moving rapidly towards us, our brain processes that we might get hurt if we stay still, so our response is to move. Our three ‘bonus senses’ (as I like to call them), are arguably the most important senses for effective sensory processing, particularly in the context of neurodiversity.

·        Proprioception is information sent to our brain from receptors in our muscles, joints and tendons about where our body is in space. If I were to get you to close your eyes and then I move your hand into a ‘thumbs up’ or ‘thumbs down’ position, it is proprioception that would be able to tell you which position your hand is in.

·        Vestibular input is information sent to our brain from our inner ear about balance and motion. It is vestibular input that lets us know if we are upright or lying down, moving or standing still, spinning or falling over. If you have ever experienced vertigo, you will know what it feels like to have challenges with your vestibular system.

·        Interoception is our brain receiving and making sense of input from our internal organs about our internal state. It helps us to know if we are hungry, thirsty, need to go to the toilet, too hot or too cold.

Children with autism and/or ADHD have significant differences in the way that they receive, process and respond to sensory input, which can interfere with their ability to go about their daily lives. They often require more proprioceptive input than neurotypical people, just to feel calm and regulated enough to participate in day-to-day activities, which often presents as difficulty sitting still. Children with autism and/or ADHD can often be over or under-responsive to vestibular input, usually differentiated by whether they are a child who loves to excessively spin, climb and swing, or whether they avoid these activities at all costs and get motion sickness even from a five-minute drive down the road. Challenges with interoception can present as challenges with toilet training, wearing the wrong clothes for the weather, and something we’ve all been guilty of: ‘hanger’ (becoming angry out of hunger).

Conclusion:

Sensory processing is a complex skill, and it impacts on everything that we do. The great news is researchers have been studying sensory processing for years and there are a number of strategies to support people who have challenges in this area. Each child is unique in their sensory preferences, sensitivities and tendencies. Working with a paediatric occupational therapist can help you identify your child’s individual sensory profile, in order to come up with strategies to help regulate their sensory systems so that they can thrive and fully engage in activities that are meaningful and important to them.