So where is this vestibular system? And what does it do? Why is it so important in the Sensory Integration approach?
Vestibular system is present in the inner ear and plays a very important role in detecting movement of head in relation to the rest of the body. It works very much in unison with the visual and the auditory system.
So, what does that mean? In simple terms-you may close my eyes and make me sit on a swing or in the car or in the roller coaster ride or a revolving chair or think of anything that moves, this system will tell me where I am and in which direction I am moving and the speed at which I am moving. All this complex information with just the vestibular system. Amazing !!
So from the example above, it is very clear that the vestibular system will sense movements
- In a vertical plane like jumping or bouncing on a ball.
- In an angular plane-like sitting on a swing
- In an orbital plane- sitting on the merry go round which goes round like earth around the sun.
- In the horizontal plane- sitting in a car or riding a bicycle.
- Rotation –moving around in rotations as we used to do when we were kids –go round and round and round till the world goes round and fall down and still see the world moving.
Also, we are very clear with our body and also very accurate about which direction feels comfortable and what speed is comfortable. When my son plays down on the swings and I swing him fast, he tells me –“So do you want me to fall off the swing?” or when I go slow , he would say “Am I a baby?” So you can see how well the vestibular system checks speed and also knows what speed is comfortable and which is not.
Another amazing thing that it does is tells me when it is enough – so I went to my sisters house and she had a swing in the living room. I kept swinging and chatting for more than an hour and then I can sense and alarm inside telling me to get off the swing and that it was enough for me. This is the body’s way to protect the system.
Vestibular system has very strong connections with
- Eyes-have you noticed that the world moves round and round after we go round in circles-so it is not actually the world moving but the vestibular system moving the eyes-telling us “Ok, you have stimulated me enough!! Just stop now”. Technically, it is called as Nystagmus.
- Brain-we feel giddy after we go round in circles-the vestibular system tells the brain- “come on dear! It’s enough for me for now”. This is its way to stop excessive input and to prevent what is technically called as “Vestibular Overload”
- Autonomic nervous system- How many of you have felt nausea after going round in circles or feel some “weird” feeling in the stomach? This is one more connection that it has to stop excessive input.
- Muscles of the back- Have you noticed that we sit on a swing- we automatically get erect. This is one more connection by which this system maintains the tone in the postural muscles.
- Strong connections with the cerebellum-This is how the vestibular system helps us to balance. So, when we are giddy after a lot of spinning, we lose our balance.
- Proprioceptors- The vestibular system has strong connections with the proprioceptors and they work like hand in a glove.
- Reticular activating system- This is like a switch which either makes us alert or dulls us down.
So why do we need to know so much about this VESTIBULAR SYSTEM??? Until now we spoke of what the vestibular system does and now what if it is not doing what is meant to do????? CHAOS!!!!!
One important thing about this system is that the imbalance of the vestibular system effects is felt in other systems.
- Visual spatial map-which in simple terms means an understanding of the world and the space around us- is distorted. They will have difficulty learning movements or actions that require timing and sequencing.
- The child will also have a difficulty in moving in dark places because he relies on vision for the map. There will be an underlying anxiety and depression.
- A person with sensory processing issues will have difficulties with visual perception- words are all scrambled-spellings do not make sense. Sequence of spellings is difficult to remember and retrieve giving an appearance of learning disability
- Child may go round in circles and will not get a signal when to stop so the protective mechanism to protect the brain is not working which will lead to overload symptoms-headaches, nausea, vomiting, changes in heart rate and respiration, yawning and changes in skin color.
- Feeling of fatigue and very low stamina or not sensing that the body is tired and needs rest so they seem to be filled with lot of energy.
- Some kids may completely avoid movement to some others who would always seek movement. They may rock themselves.
- Movements of the kids would be very clumsy and uncoordinated.
But, we can work and improve the functioning of the vestibular system and help these individuals.
Isn’t it really amazing to understand how big a role this little vestibular system plays in our life!!!