Just what is the vestibular system?
The human vestibular system is the underpinning of the central nervous system (brain and spinal cord). Our eyes and inner ear semicircular canals and otolith organs represent the receptors of this system. This system functions as an integration of other (touch, etc) systems and consists of numerous pathways that extend through the brainstem located above the spinal column in the lower rear portion of our brain.
In a typically developing central nervous system, the vestibular system assists us to maintain appropriate levels of arousal and attention, conduct us as we move through space, and facilitate static or dynamic balance and numerous other automatic functions. “Feeding” this system helps to smooth neurologic pathways enhancing brain development. As we like to say, “Movement and touch is the basis for neural development” hence the maternal instinct to rock and swaddle our babies. Rocking stimulates the vestibular system and innovative baby swings deliver multiple planes of movement stimulating each semicircular canal. Swaddling is a deep touch experience and modulates and calms and the central nervous system. In therapy, we use weighted blankets and deep pressure to achieve a similar outcome.
All said, the vestibular system is imperative to the emergent brain. For many years, both PTs and OTs have understood that children provided with sensory motor breaks during the school day (recess) will function, attend and learn more effectively in the classroom. Recent studies employing 4 short recesses per day have yielded improvements in classroom focus and attention and test scores. Educators are quick to call this “new” idea brain-based learning but these principles have been the basis of OT, and PT of late, since the 1960’s thanks to the theory of Sensory Integration developed by A. Jean Ayres, PhD, OTR. Dr. Ayres, a woman ahead of her time and pre-dating brain imaging, is the principle behind Sensory Integration (now called Sensory Processing) Theory and Application. With onset of imaging technology, we are now able to visualize literal evidence of brain change.
So what does this all mean and how does equine-based work impact this process? Therapists who are educated and properly trained in this theory and application can determine the relative responsiveness of vestibular and proprioceptive (deep touch) systems. Some children are over responsive to movement and touch and some are under responsive. In both scenarios, the child can present as either over or under aroused by sensory information in the environment. A child who is sensitive to movement, touch, sound or lights may be more apt to “melt down” when overstimulated. A child with a low arousal state may constantly want to sit negating his ability to interact in the environment. In either situation, the brain is not properly organized to learn new information. In our jobs as therapists, we assess the response to input during activity and grade the input during meaningful activity in an attempt to elicit that “just right” response. E.g. eye contact, following directions, communication, etc. So…therapists who are properly trained in Sensory Integration and the science behind use of the horse in PT, OT, ST (hippotherapy) have an extraordinary chance to impact neural development. Using hippotherapy, therapists use the horse as a dynamic moving treatment surface. The horse provides us with multiple movement prospects and we can grade this input by changing the child’s position on the horse, the horse’s gait, the gait transitions (from walk to trot to walk, etc. ), the ring figures (circle, figure of 8 etc.). In addition, as our auditory and language pathways lie so close to the vestibular receptors and pathways when we add auditory input (metronome or music) we amplify the experience. In therapy, use of the horse is THE PERFECT tool. Lastly, as the human to animal bond positively impacts process and connection, we are providing our children with a superior method to aid brain growth and development.