We briefly discussed sensory challenges in our 4th of July blog. Sensory systems and sensory integration play a large part in the way autism is expressed. Before we discuss the various ways ASD affects the sensory systems let’s address the way our senses are supposed to work.
The 8 senses
There are different ideas regarding how many senses we possess. Most people are familiar with five main senses, i.e. Vision (sight), Audition (hearing), Olfaction (smell), Gustation (taste), and Somatosensation (touch). In addition to these well-known senses, there are at least three more that impact individuals with Autism and Asperger’s syndrome. These three senses are “Proprioception”, “Vestibular sense”, and “Interoception”.
When everything is working well with our sight, we receive a clear picture of the world around us. In our central vision, for example, we are able to discern objects or people in the foreground and background. We see changes around us. Our peripheral vision helps us notice things going on to the sides, and is used to determine if we should shift the focus of our central vision.
Hearing is very important for communication with others as it monitors the sounds of our world. Similar to vision, our sense of hearing is used to determine what to pay attention to, and what is background noise.
Our sense of smell is underestimated as far as its importance. Smell tells us if our food is edible or rotten. Scent is closely associated with taste. In fact, without smell, there is almost no sense of taste. A smell can trigger memories and feelings. A smell can identify things to avoid, and things that are pleasant.
Taste, like smell, encourages us to eat or spit something rotten or poisonous out.
Touch, similar to Gustation, warns the body of what is OK and what is harmful. Things may be soft or sharp, hot or cold, hard or soft, slippery or sticky.
Those are the senses we know fairly well. Now, let’s discuss the remaining three.
Proprioception tells where the body is. It is how you know where your feet are resting or what your hands are doing. Proprioception also tells you how much force you need to lift a glass filled with water, versus a glass half empty sometimes called muscle sense. It is the sense that helps you move your body where and in a way that you want to.
The Vestibular sense
The vestibular sense is responsible for your balance. It keeps you steady as you move and monitors your orientation to the world.
Interoception is how your body understands and interprets the cues from within. i.e. a grumbling stomach may mean hunger, flushed cheeks may indicate anger, embarrassment or overheating. It takes all the internal cues and determines what is going on. With this information, we make decisions as to what we should do.
All the senses work together to give us a full picture of the environment and to determine how to act. This is called sensory integration.
Through sensory integration, we notice the differences in our environment and apply what we know in making decisions. How does sensory integration work? Let’s look at an example, e.g. stepping onto a canoe.
Picture yourself standing on the dock, about to climb into a canoe. You put your foot down into the canoe, (vision and proprioception) and as you begin to step in, the canoe starts to rock. Automatically you adjust your body to keep yourself balanced (vestibular sense) and slowly sit down, placing yourself in the middle of the seat.
Another example is having a conversation. You listen (hearing) to a friend telling a story. He is smiling as he tells the story. Your sight tells you he is having a good time.
There are many, many more examples of senses working together.
In the next blog, we will discuss what happens when our sensory systems are dysfunctional.
Rebecca J. Weaver is a Certified Autism Specialist at Independent with Autism, working to empower individuals with ASD. Need help creating positive strategies? Check out IndependentwithAutism.com for more information.
What is Interoception? The 8th Sensory System by: Heather Greutman