Why is proprioception so important?
The first reason, as I mentioned above, is that our proprioceptive sense lets our brain know where our body is in space. Another example of this is walking. You don’t need to look down at your feet to know where they are. You don’t need to look to lift your foot up, move it forward and then place it down again. These movements just happen because your proprioceptors send constant sensory information to your brain about the position of your hip, knee, ankle, and toes. This ensures they move into the right place.
Each time we move the propriocepetive feedback from our muscles and joints tells our brain where our body is. This includes any time we move our arms, legs, hands, feet, neck, or spine. Even when we are still, the stretch of the muscles, or lack of stretch, and the joint position tell our brain where we are.
When you’re watching TV you can reach over to the controller and find it, if needed, without looking. It is your proprioceptive system that sends your arm to the right place. Your touch sense might feel around to locate the controller but your proprioceptive system then opens your hand and helps you to pick it up, direct it towards the TV and press the button.
Grading of force and speed of limb movement
When you press that button on the controller you need to press it with enough force to make it work. It’s important to not press it too firmly however as it might slide out of your hand or break. This is called grading your force. We do this all the time quite naturally and without thinking about it. Our proprioceptors are doing the thinking for us.
You also need to move the controller with the right speed so that you don’t crash your hand into yourself or another person. It’s the same with the cup we mentioned earlier. This is your speed of limb movement.
If we use too much force or speed we break things. If we use too little then we might not be successful. When hammering in a nail, for example, if you hit too hard you might bend the nail, but if you hit too softly it won’t go in. Cracking an egg is another great example, if you tap too lightly it won’t open, but if you crack it too quickly or with too much force you will be cleaning up a mess!
Proprioception is what allows our limbs to move into the right position, with the right speed and the right amount of force required for the activity.
Proprioception and muscle tone
Muscle tone refers to the constant partial contraction our muscles are making when we are still. It allows our bodies to increase or decrease tension as required when moving. Our proprioceptive system helps our vestibular sense to support this tension. Some children with Sensory Processing Disorder might have lower than average muscle tone and this can affect their postural control and stability.
Proprioception and balance
Finally, our proprioceptive sense helps to support our balance. It again works with the vestibular sense, which is primarily responsible for balance. Our proprioceptors give our brains even more information about where our body is and this helps with our balance. For example, if you step on an unstable surface, you receive vestibular information from your inner ear about the change in head position and you receive proprioceptive information about the position that your ankle, knee, and hip are in. The combination of this information helps your body keep upright and not fall over.