VESTIBULAR TREATMENT FOR CHILDREN WITH AUTISM

"Children with autism might not be receiving or processing vestibular information effectively. It is possible that, instead of augmenting accurate vestibular information, the visual and proprioceptive systems are providing all the information they use to navigate the world."

BY ROBIN ABBOTT, MS, OTR/L

As an experiment, walk through a room and choose to stop directly on the threshold of the doorway. As you do this, think about the planning involved. Estimating the steps remaining to get to the threshold (which can be done visually, based on the speed with which the doorway seems to be approaching), and when you need to slow down to achieve stillness just when you want to (which can be sensed proprioceptively – using your muscles and joints).

Now, as you stop, pay attention to the muscles involved in halting your forward momentum, and all the associated muscles that have to contract to keep from using too much force to stop, and actually falling backward. These split-second reactions can only be processed and executed accurately by using vestibular information.1 The other two methods, vision and proprioception, require more cognitive processing and depend on potentially unreliable information. The visual method of orientation could break down if it gets confused by movement occurring beyond the doorway, or if it is limited by low lighting. The proprioceptive system can be thrown off by a change in walking surface, such as hard floor to carpeting. But the vestibular system provides accurate information that the body uses quickly and reliably, because of its direct connections to the motor centers of the brain and the skeletal muscles.

MOVED TO TEARS: To engage with a toy he was interested in, Steve would place it on the floor, and when it was moved, he became upset, even if it was still within reach. Without an accurate sense of where he was in space and what direction to move in, as well as difficulty coordinating his gaze in the correct direction, moving was intimidating far out of proportion to the threat it presented, and Steve strongly resisted movement out of anxiety, and possibly fear.

Located deep within the skull, on either side of the head within the inner ear, the vestibular system provides "a unique and complete description of head motion and orientation in three dimensions"2 by providing information regarding: 

Children with autism might not be receiving or processing vestibular information effectively. It is possible that, instead of augmenting accurate vestibular information, the visual and proprioceptive systems are providing all the information they use to navigate the world. This may help to explain some of the difficulties children with autism have in moving their eyes to a target (such as someone's eyes), sequencing and connections between events and situations (knowing what comes next), and navigation through the environment (as opposed to being lead).

As the saying goes, "if you've met one child with autism… then you've met one child with autism." Children with autism present with such a variety of difficulties and abilities, how can one system, the vestibular system, explain such a wide variety of behaviors? There is some evidence that the degree of impairment of the vestibular system can result in different behaviors. In a study on mice in which vestibular function was chemically compromised, researchers found that the severity of vestibular impairment resulted in different behaviors; more profoundly impaired mice manifested hyperactive behaviors, while less severely impaired mice exhibited signs of anxiety. 3 Both anxiety and hyperactivity are behaviors common in children with autism. 

As an occupational therapist with years of experience with children, I would consider another factor that plays a role in how a child completes tasks within the world when their vestibular information is unreliable: do they compensate for the missing information using their vision, or their proprioception (joint and muscle feedback)? As illustrated at the beginning of this article, the brain augments and confirms vestibular sensations using visual and proprioceptive input. Some children may come to rely on these forms of information excessively or exclusively. This can result in very different behaviors and abilities.

For a child who orients to the world using their vision, behaviors like anxiety, whininess, hypersensitivity to movement and inflexibility in routine are common. Take my young friend Steve. At three-and-a-half years old, Steve had been diagnosed with autism for about a year. As might be expected, made little to no eye contact with others. He had a vocabulary of about 25-30 words and could follow some verbal cues. He liked to line up his toys (particularly trains), and play on the floor, lying down with his head resting on his arm. If he was engaged in play, he did not like to transition to a new activity. He would whine and cry, but did not hit or act out physically. He became upset in new places and would passively resist movement to a new location; his parents regularly had to carry him to new places, and this became more of a burden after the birth of his younger sibling.

Upon examination, Steve was unable to "Not only does the vestibular system fact-check the physical experiences we are having, it also helps us predict that will happen in the physical world." follow a toy visually across the space in front of him. To engage with a toy he was interested in, he would place it on the floor, and when it was moved, he became upset, even if it was still within reach. It was as if he couldn't find it with his eyes.

 It is my assumption that Steve visually "locked on" to objects to orient himself. As if his brain was telling him, "this toy is not moving, so I must not be moving either." But the world around him did not stay still as he was expected to navigate from place to place. Without an accurate sense of where he was in space and what direction to move in, as well as difficulty coordinating his gaze in the correct direction, moving was intimidating far out of proportion to the threat it presented, and Steve strongly resisted movement out of anxiety, and possibly fear.

Gerald is a good example of children I assume may be using their proprioceptive input to compensate for missing vestibular information. At seven years old, Gerald's mother was worried about his disconnection from people, physically aggressive tantrums, and inability to stay on-task. This created many problems in school, as he seemed unable to learn new information because he didn't seem to be "present," talking about completely unrelated subject matter during class and unable to answer questions. Sitting for even a short lesson was often too much for him, being unable to stay in his seat.

Upon evaluation, Gerald, like Steve, had very poor control over his eyes. He was constantly on the move, bouncing around the room and pulling toys out without stopping to explore or play with them. With this constant movement, he would become more and more "hyper" and disorganized. His mother's solution to short-circuit this was to offer him a tablet device, which he would sit to play on as long as she would let him. If he continued to "ramp up" through physical play, it often ended in a violent tantrum or him accidentally hurting himself or someone else as he became clumsier and more hyperactive. It was my assumption that he was using his muscles and joints to stay "grounded" and feel safe, but because he had no sense of where he was in space, the movement made him more disoriented as time went on. Sitting with his device allowed him to orient to that one point in space, the screen, but did not allow him the opportunity to "reset" and orient to his surroundings.

For both Steve and Gerald, their vestibular system wasn't giving them information that allows the accurate development of a brainprocess all of us use every day, all day, called "feedforward". Not only does the vestibular system fact-check the physical experiences we are having, it also helps us predict that will happen in the physical world. In their 2005 summary of the functions of the vestibular system, researchers Brian Day and Richard Fitzpatrick state that the vestibular system "provides our brains with a deep and special understanding of how the force of gravity moves things, from the fall of our body as we lift our foot to take a step, to the fall of a ball during a game of cricket. In all of these situations, the brain predicts the trajectory of fall with startling accuracy." That is feedforward. We learn how things move when affected by gravity, because we first understand how gravity affects our own bodies; from the increased muscle action needed to control our head balanced on top of our neck, to the feel of horizontal movement when we're being carried versus vertical movement as we are set down, to the coordination of our eyes and ears around our center as we rotate left and right. All these sensations must match up accurately and consistently, to build a database of vestibular sensory experiences that allows us to translate our experiences into guesses about how gravity affects other people and things.

Without the ability to build a feedforward paradigm that allows a child to begin to predict physical interactions, the world remains an unpredictable and unsettling place. A child doesn't come to learn how much force it takes to hug, versus tackle, someone. Or when an object will fall, versus when it is stable on a surface. Or when an object moving in a particular direction, such as a car, will continue to move in that direction. These predictions about what is likely to happen play a big role in the development of emotional stability, the ability to learn new information, and the development of connections with others through play and physical contact (e.g. learning the force it takes to roll a ball to another person, or building a block tower that will stay put). The vestibular system is what allows for the development of feedforward, and feedforward allows a child to correctly predict actions and consequences, giving them emotional and physical stability in the world.

Having fun is the work of childhood. And it can happen more easily and more often if a child has a functioning vestibular system that makes them feel secure, effective and successful. •

ABOUT THE AUTHOR: Robin Abbott, MS, OTR/L is an occupational therapist with 12 years' experience working with families and children with autism, ADHD, SPD and Down Syndrome. Her practice is a theoretically-based, structured framework of auditory and vestibular activities to promote better sensory integration. She is currently works as a Rehab Liaison in Davenport, IA. She can be reached through her website, rabbottwriter.com

VESTIBULARLY-FOCUSED THERAPY : RULES OF THUMB

So, if the vestibular system is not functioning appropriately for some children with autism, what can be done about it? Your child may already be getting some vestibularly-focused therapy, especially if they receive outpatient, clinical occupational therapy, as this type of treatment tends to be the purview of OT. But there are some rules of thumb that my time in the clinic with children has proven to be more often true than not.

1. Vestibular treatment should begin by NOT actively asking the child for a response. Imagine if you had not been able to see for a long period of time, and suddenly your sight was restored. Wouldn't you spend some time just looking around, feeling what it is to see, before you start interacting with your world using vision? When a child feels a vestibular sensation strong enough to register it, after a long time NOT feeling those sensations, they need a moment to get used to it. Also, when we ask for them to participate, such as by keeping their balance while playing a game, they will most likely use their "back-up systems," vison or proprioception, to complete the task, instead of learning to use these new vestibular sensations. Passive movement, on a swing or rotary board is almost always where I begin.

2. There is a large part of bodily coordination that is built around our understanding of what direction "straight down" is, especially straight through the center of our bodies. This sensation is highly dependent on a part of our vestibular system called the saccule. The saccule is noticeably activated when you feel "heavier" as an elevator suddenly moves to take you up. So, any up-and-down movement that activates this sensation should be part of therapy. Passive bouncing on a big ball and large swinging arcs are my go-tos.

3. Once I'm sure the child is sensing vestibular input, then it's time to put it into practice with balance skills and games. Some of these activities should be seated or stationary, like standing on a stepstool without losing balance, or sitting on the floor in cross-legged to play a quiet game, without using one's arms to support oneself. Being in control while still is a challenge for those children who use their proprioception excessively, and physical control when on the move is a challenge for those children who anchor themselves visually. I know I'm making good progress with a child and helping their vestibular sense when they can do a task that was difficult or uncomfortable for them, and have fun doing it.