Week 5; Summary 1

In her article, Internal Senses, Michelle Colletti provides the reader with a knowledge of the sensory systems; namely, the proprioceptive and vestibular systems. She explains that the body contains millions of tiny receptor cells called proprioceptors. These receptors relay messages to the brain regarding when and how the body has moved. This provides our body with a sense of where it is in relation to the external environment.

Our vestibular system is one that sends information to the brain when the head is in motion. She uses the example of turning our heads once we hear our name called. The vestibular system is the system that tells our brain that the head is in motion. The brain is only receiving information from the brain and therefore concludes that only the head is in motion, not the rest of the body. This system has a very significant impact on everyday functioning.

The Reticular Activating System (RAS) is an area in our brainstem whose job it is to “wake us up”. The vestibular system sends information directly to the RAS. This is a reason that children with sensory processing disorders cannot sit still: they are trying to keep themselves awake by providing themselves with outside stimuli to do the job. Therapists often suggest “heavy work” for children with sensory processing disorders because it helps inhibit excessive vestibular activity that may otherwise cause problems (i.e.: lack of attention).

For the body to function accurately, it must gather the proper information from the external environment to provide itself with an internal sensory picture, or body scheme. The information from proprioceptors located at joints and muscles help coordinate body movements to cause appropriate functioning. Children who have sensory processing disorders do not receive the necessary information to provide them with an accurate body scheme; resulting in a general clumsiness.

The vestibular system sends messages from the brain to the muscles and joints, keeping them firm and ready to respond (muscle tone). Children who struggle with sensory integration often have low muscle tone, which means that the information regarding outside stimuli is not being sent to the nervous system.

One way that occupational therapists help children with sensory processing disorder is by providing them with sensory input that allow their bodies to move and their muscles to work in hopes of strengthening both the proprioceptive and vestibular system. The more activities they participate in that they enjoy, the longer their attention span will be.

Colletti, M. (2009). Internal Senses. Retrieved from http://www.watersedgehealing.com/articles/Internal_Senses.pdf