You’ve heard them all… sensory overload, sensory integration dysfunction, auditory hyperacuity, sensory processing disorder, and the “out of sync” child, are all ubiquitous terms in the autism field. Every parent or teacher of children with autism spectrum disorder knows their child or student reacts in usual ways, often very negatively, to some sounds, and they tend to visually fixate on moving objects, flickering lights or vertical lines, such as waving lines (like wiggling a pencil back and forth in front of their eyes).
Some children cover their ears or eyes and wave their head back and forth in the presence of certain sounds. Nearly without exception, parents of children with autism tell me their child has “sensory integration” problems, which is presumably what they have been told at the time of their child’s diagnostic assessment was conducted, or school team special education evaluation meeting was held. Parents didn’t spontaneously come up with the notion of a “sensory integration” deficit or “sensory processing disorder” on their own, though they all correctly note that their child often reacts negatively to loud sounds, sirens, bright lights or sometimes textures or smells. Until Jean Ayres (shown below) book was published in 1970 (Sensory Integration and the Child), while unusual responses to some stimuli were widely recognized among parents and professionals, children with autism were not known to have a sensory integration disorder. She invented that idea out of whole cloth. Let’s take a step back for a moment.
Motor Therapy: There is strong evidence that specific Occupational Therapy activities designed to improve fine and gross motor skills can be very helpful to many children with autism, such as grasping a spoon or pencil, printing or writing, buttoning, lacing and tying shoes, pressing buttons on a phone or computer balancing on one foot, walking up and down stairs, running, throwing and catching, and so on. Motor Apraxia is common in autism Motor apraxia is common among younger children as compared with older children motor apraxia (34%) (Ming et.al. 2007; Dowell et.al. 2009; Dziuk, et.al. 2007). A special set of helpful OT skills are involved in treating Oral-Motor Apraxia, coordinating the movements in the mouth, such as tongue, breathing and swallowing, permitting a child to chew and swallow food and to speak (Hayden and Square, 1994; Law et.al, 2004). OT’s often refer to them as Praxis or Motor Planning activities. Praxis is a Greek word used to describe the learned ability to plan and to carry out sequences of coordinated movements in order to achieve an objective. Such skills require repeated practice coordinating responses with kinesthetic feedback from having made those responses in proper coordinated sequence. I say this because I don’t want to create the impression that I am opposed to Occupational Therapy as a profession, which can have a great deal to contribute to improving practical functioning of many children with autism. We have had excellent experience combining OT-suggested motor coordination interventions with behavioral intervention strategies to gradually promote persistence and enjoyment of motor skills development activities. The comments in this the remainder of article are specifically about the notion of Sensory Processing Disorder, not overcoming dyspraxia, which is a well established neurological medical condition.
What is a Disorder? A disorder is a functional abnormality or disturbance. Medical disorders can be categorized into mental, physical, genetic, emotional and behavioral disorders. The term disorder is used primarily to identify abnormal conditions that are not caused by infectious organisms such a bacteria or viruses. Disorders often have known physical causes (e.g. metabolic disorders or epileptic disorder), characteristic measurable features, epidemiology within a population, a characteristic course and established treatment and prognosis. Just because a group of people deviate from a norm doesn’t mean they have a disorder. For example, most people from Viet Nam are shorter on average than most other people throughout the World, but that doesn’t mean they have a disorder. A set of symptoms deviating from the norm can be caused by another condition, but are not themselves a disorder. The fact that some people lose consciousness, and exhibit abnormalities of muscle tone with violent contractions and relaxation of muscles, is in itself not a disorder, but epilepsy is a disorder that causes those symptoms. Neurologists don’t attempt to treat the violent contractions, except in emergencies, but they treat the physiological or physical brain abnormalities giving rise to the seizures, using medication or surgery. If they administer a drug to interrupt a series of seizures, once the person has recovered, that has no effect on the underlying epileptic disorder.
Sensory Integration or Processing Disorder? Now that we have a definition of “disorder,” let’s try to make sense of the claim that a child has a “sensory processing,” or “sensory integration” disorder, which can be treated using sensory integration therapy methods. To do so, we need to consider each of five distinct issues, which often get muddled when trying to sort this out.
1. The first, “Is it true that most, if not all children with autism spectrum disorders react in unusual ways to various kinds of sensory input?” The answer is clearly yes. Moreover, studies by Winifred Dunn and colleagues at the University of Kansas Medical Center with her Sensory Profile assessment has made it possible to describe in some detail the specific kinds of stimuli and types of responses a given child exhibits under an array of circumstances (Dunn et.al, 1997). But assuming these differences in responding to stimuli implies the child has a specific, single, tangible, treatable disorder or disability that is causally related to the autism syndrome has not been shown. Not at all. That would be like concluding that treating the hearing problems of many children with Fetal Alcohol Syndrome would eliminate their underlying FAS. Obviously, it doesn’t. It can be very important to fit a hearing impaired child with a hearing aid, but that has no effect on his underlying FAS, which includes cognitive, behavioral challenges and often heart defects, and no one expects it to have such an effect.
An older study found hypersensitivity to sounds was present in about 18% of children with autism but not their typical peers, but by no means ALL children with autism (Khalfa S, J et.al. 1999). A more recent study conducted in France suggests children with autism tend to hear a narrower range of sound frequencies but perceive sounds they do hear, as being louder than same age typical peers (Hear Res. 2004,198:87-92). A study by Tharpe and colleagues at Vanderbilt University indicated that all physiological measures of auditory thresholds were similar among kids with autism and their matched peers, but tests requiring behavioral cooperation of the children with autism revealed less sensitivity and more variability to sounds (Tharpe. et.al., 2006). Probably has more to do with the required cooperation than underlying auditory processing problem. In summary, there is some inconsistent evidence suggesting that some measures have indicated some sounds may appear louder to children with autism, but not all.
2. The second question, is whether there are physiological brain differences associated with this tendency to overreact to some stimuli (e.g. sirens), and under-react to others (e.g. people’s speech). The answer seems to be that while there are some physiological differences, they are unpredictable and don’t clearly relate to the observed exaggerated behavioral reactions to strange sounds, tastes or textures, such as tantrums or self-injury. There is no obvious link between sound thresholds and tantrums. The above Tharpe study at the Wilkerson Speech and Hearing Center at Vanderbilt University to test this idea. Pure tones were presented to children in a classroom setting. An observer didn’t know when the tones were being sounded but simply recorded any signs of child distress, aggression, tantrums or self-stimulation. There was no association between presentation of the tones and any of these behavioral symptoms.
3. Thirdly, is there physical evidence that there is something about the way a child’s nervous system functions that indicates that a phenomenon of the alleged “sensory processing disorder,” or “sensory hyperacuity” actually exists as a measurable brain dysfunction. The answer is no, no such evidence exists. This notion is based on one of the oldest fallacies in human history, namely reification. The English word comes from the German word Verdinglichung, which refers to concluding an abstract idea or phenomen has living existence with its own independent properties, by giving such an abstract idea a name, or thingification, treating it as if it exists as a real, honest to God, tangible, touchable, manipulable thing. In other words, now that a child’s over-responsiveness to some stimuli has been assigned a name, "Sensory Processing Disorder", it must therefore exist as a real thing, which is fallacious. All we know is that the child reacts oddly to some sounds some of the time under some circumstances. Those reactions could be epiphenomenal, i.e. due to something else about autism that causes over reactions to some stimuli. I strongly support research to identify the causes (they are probably multiple) for these exaggerated responses to some stimuli, but seriously question the validity of the notion of Sensory Processing Disorder.
4. The last and most challenging problem associated with alleged Sensory Processing Disorder, is whether having identified a child as, “Having a set of unusual sensory characteristics, is there some specific thing we can do to reduce that tendency. In other words is there an objectively specifiable intervention that will overcome the condition?” A corollary is “Having conducted such treatment, are the child’s core autism characteristics reduced or eliminated?” The answer to both questions is no, there is no such sensory integration intervention that has lasting effects on the core features of autism, namely communication deficit, lack of social understanding and social skills and persistent, repetitive non-functional routines. I invite you to conduct your own literature search at PubMed or PsychLit. You will find no compelling evidence for effective treatments. Considering that Jean Ayres published her book over 40 years ago, that suggests perhaps no such evidence will ever be forthcoming.
So What Do We Make of This? In her book, Sensory Integration and the Child (1970), Jean Ayres presented theoretical argument that children with autism fail to appropriately integrate sensory input from multiple modalities, which led to the creation of the field of Sensory Integration in occupational therapy, which is used throughout the world despite lack of clear empirical evidence that it produces lasting effects on the communicative, social or other behaviour of children with autism. According to Group Dynamics in Occupational Therapy (2005), Ayres' theory and conclusions remain controversial. A 2002 article in The Scientific Review of Mental Health Practice reported that controlled studies examining the effect of Sensory Integration treatment "have found little support for the efficacy of SIT for treating children with various developmental disabilities". Controversial Therapies for Developmental Disabilities (2004) indicated that in spite of "limited and mostly negative research findings on SIT", the sensory integration approach remained popular among occupational therapists and "other professionals and clinical populations." Over a decade ago, Dawson and Watling (2000) reviewed evidence concerning occupational therapy methods and found at that time there were no controlled studies to review. The following year, the stellar panel at the National Research Council came to the same conclusion (Lord & McGee, 2001). They found several studies using Sensory Integration Therapy specifically and concluded, “Five studies of auditory integration training were found. Results of these studies provided no, or at best equivocal, support for the use of auditory integration training in autism.” The American Speech-Language Hearing Association Working Group on Auditory Integration training issued a report on AIT in 2004, http://www.asha.org/docs/html/TR2004-00260.html concluding that of the six studies testing AIT in autism, none present evidence the method is effective in reducing hyper-responsiveness to sounds.
Why Caregivers are Attracted to Sensory Integration: Parents and schools are attracted to sensory integration activities because they can see something very tangible occurring before their eyes, which is being done to, and with the child, by a caring, helpful adult, such as an OT, teacher or parent. And what is being done is often very emotionally appealing (e.g. such as holding or swinging a child) and often fun for the adults. Many children seem to enjoy some SIT activities, but not all. Some kids balk and scream at being held tightly or brushed or presented with pulsating lights or sounds. Adults usually reinforce the tantrum by stopping their brushing or hugging the child.
Parents often take pleasure in conducting the SIT activities on their own, which provides a professionally-sanctioned activity which they are able to do with their own child, which is often difficult otherwise. It makes parents feel they are actually doing something to help their child. It is fun to blow bubbles with your child, or massage her or wrap him in blanket and hold him in a hug, or run water through his fingers as he giggles. What can be wrong with that? Nothing, but don’t expect it to have any effect on your child’s core autism symptoms. You need to understand you are doing this because it is an enjoyable activity to do with your child, but it is very unlikely to produce any long-term benefits.
In short, it is really a misnomer to call it therapy, meaning a treatment that produces improvement in a condition or disorder. By all means do things with your child that s/he and you enjoy, but don’t confuse it with treatment designed to produce lasting improvements in their social and communication skills and reduce their rigid, repetitive non-functional routines.
Sensory Diets, Pretend Therapy: A very popular idea with parents and some teachers, is the use of Sensory Rooms and a “sensory diet.” One company in particular has promoted this notion, the SNOEZELEN company owned by ROMPA in Chesterfield Derbyshire, UK. They say on their website that, “Children and adults with disabilities or other limiting conditions (who doesn’t have some kind of “limiting condition?”) enjoy gentle stimulation of the primary senses...Participants experience self-control, autonomous discovery, and exploration-achievements that overcome inhibitions, enhance self-esteem, and reduce tension. Free from the expectations of others and away from the pressures of directed care, they recuperate (recuperate from what?) and relax. Research has shown that multisensory environments offer a wealth of benefits, often affording the participant and caregiver an opportunity to improve communications, enhance their understanding of each other, and build trust in their relationship.” I have done considerable literature research attempting to find any empirical evidence of such benefits and have found none. Zero, nada, as in none. There are testimonials galore, but no research. I have found no measures of self-esteem, improved communication or understanding among children and adults, and certainly no evidence of recuperation, as claimed resulting from the use of Sensory Diet. Nor have I found any evidence of lasting reductions in compulsive repetitive behavior or increases in social skills or communication associated with use of Sensory Rooms. None whatsoever.
If one does a search of what is involved in setting up a “Sensory Room,” several suggested lists of supplies and equipment can readily be found on the internet. Here are just a few examples: LED lights strips, 54 inch bubble tower, laser show machines, liquid light projector, Black Lights and accessories, Mathmos Lights, Fiber Optic Sphere, Beanbag Chairs, Sheepskin Rug, Mini-Bubble Wall, guided imagery tapes, relaxation music, nature sound machines, heartbeat sound stuffed animals or blankets, metronomes, vibrating teethers, blow toys, musical instruments, rubber tubing, ‘Nuk” toothbrush, “Blow Darts,” kazoos, “Z-vibes,” “Jigglers,” tactile toys and balls, textured walls, vibrating toys, ball pits, “Somatron” vibrating mats and cloud chairs, and the lists go on and on and on. The photos of “sensory rooms,” available on the internet suggest they were designed by adults who grew up in the1960s in the heyday of psychedelic light shows, for those old enough to remember the Jefferson Airplane at the Filmore Auditorium or the Jimi Hendrix Experience at the CNE Auditorium, though the sound level is obviously much lower. Sure must be a lot of fun for the parents, OTs and teachers, and hopefully doesn’t terrify the kids too much. Some of it is likely to provoke self-stimulation among some kids, but what the heck, while it doesn’t do any good, it’s not the end of the world. On the other hand, I have considerable reservations about the appropriateness of parents using Federal Medicaid Waiver money for such purposes since there is no evidence of benefit.
Lack of Empirical Evidence: There is evidence many children with autism react negatively in exaggerated ways to some stimuli, most often sounds. In addition, they tend to become narrowly focused on some intermittent visual stimuli and incorporate them into self-stimulatory behavior patterns, while being unresponsive to others, such as spoken speech. There is some evidence of differences in physiological auditory measures involving the child’s cooperating with the examiner. Physiological measures that don’t rely on cooperation with the audiologist, generally show few if any auditory functioning differences among children with autism and typical peers. There is little or no evidence from controlled studies that Sensory Integration Training produces any lasing effects on core autism symptoms, though several studies have suggested transient reductions in stereotypic activities, such as rocking or hand-flapping for up to a half hour immediately following SIT activities.
History Repeats Itself: Many professionals and parents have bought into Jean Ayre’s “Sensory Integration” theory, and are having great difficulty retreating from their stated commitment in the face of a large body of evidence indicating this is not a meaningful term for an actual condition that can be effectively treated as proposed. This situation is very reminiscent of what happened in psychiatry in the 60s when much of psychiatry was dominated by psychoanalysis, which was largely abandoned by the 80s, along with Bruno Bettleheim’s damaging ideas about the alleged maternal cause of autism. Many psychiatrists continued to cling to Freudian psychoanalytic theory and treatments long after everyone else in the mental health and psychopathology fields realized it was a misguided approach lacking empirical evidence. Eventually health insurance companies stopped paying for psychoanalytic therapy, at which point practical exigencies led most psychoanalytic therapists to either retire or switch to other types of treatment.
Costs of Ineffective Services: Most children with autism in the US receive occupational therapy services that incorporate sensory integration training, either in school or privately, the latter usually paid for by medical insurance. Private OTs generally charge $100 per hour for Sensory Integration Therapy through private agencies. School-based OTs are paid $61,590 to $75,260 per year or about $30-36 per hour. Over 300,000 children with autism receive special education services through public schools (CDC, 2006), or conservatively $9 to $10.8 million per year (minimum) plus the cost of private Sensory Integration Therapy at three-times the cost. If you run the numbers, you can see that a sizable amount of money is being expended for Sensory Integration Therapy for which there is little evidence of benefit. Substantial money is at stake for the therapists and the general public in terms of the cost of health care insurance.
I haven’t tried to calculate how much it costs to create a “Sensory Room,” and provide individualized “sensory diets,” for children with autism. The cost could be very substantial to individual families or school programs, in some cases thousands of dollars per family or school, and there is no evidence whatsoever that it is beneficial. It may be great fun for the caregiving adults, but of no real benefit to their children with autism. Parents obviously enjoy creating a room full of weird pulsating pink, blue and green lights, use of UV dark-lights, and fur rugs, vibrating mats and cushy squeeze toys, with pulsating heart beat or nature sounds.
I know, I’m a wet blanket at the party. I can just hear a parent who recently spent a bundle constructing a “Sensory Room,” in their home saying, “You’re no fun…. You’re a party-pooper.” I confess, I don’t subscribe to channeling dead relatives, faith healing or Sensory Diets, as much fun as those activities may be for some people, and very lucrative for others.
There is no empirical evidence for any of them. Couching an intervention in the language of science does not make it scientific. Phrenology referred to treating people based on bumps on the skull, which surely must have meant it was scientific. No, not really. It was a made up theory of Franz Joseph Gall, without any scientific basis. Sensory Integrative Dysfunction… Sensory Integration Therapy… Sensory Diets? Same deal. Made up stuff with no convincing scientific evidence that this is an actual, treatable condition. Misleading parents into believing they are helping their children overcome their core autism symptoms, when there is little credible evidence to support that assertion, raises ethical questions.
Fun is really important for everyone. Eating a hotdog and drinking a coke with your family while watching a baseball game on a sunny July afternoon can be really fun, but it isn’t therapy. Fun is especially important to kids with autism when it involves shared experiences with their parents, but it isn’t usually the same as therapy or treatment. Treatment, which can also be fun at times, such as Pragmatic Speech Therapy, or Oral-Motor Apraxia therapy, Intensive Early Behavioral Intervention alone or combined with other approaches such as the Denver Early Start Model and LEAP, produce long term improvements in core autism symptoms enabling most kids to function reasonably well in school, home and the community. If you want to have fun with your child with an ASD that is more likely to have lasting beneficial effects, collaborate with your child’s therapist, speech/language clinician or special ed. teacher to prepare her or him to go camping, or go on a family picnic, or a ball game, a trip to the zoo, or to a county fair and check out the hay bailers and the cows, and eat an ice cream cones… do cool stuff (see Thompson, 2008), but don’t fool yourself into believing flashing LED lights, soft cushy rugs, a hammock or massaging are going to cure your child of her or his autism, or for that matter, even significantly reduce his or her symptoms.
American Speech-Language Hearing Association Working Group on Auditory Integration training. http://www.asha.org/docs/html/TR2004-00260.html
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*The very popular Peabody award-winning children’s radio show Let’s Pretend, which began broadcasting in 1934 on Saturday mornings, had an audience full of children beginning with Uncle Bill Adams' salutation, "Hello Pretenders!" followed by the response "Hello, Uncle Bill!" The show presented adaptations of classic children's stories and fairy tales like Rumpelstiltskin, Sleeping Beauty, Thumbelina and many, many more. Everyone understand they were “pretend” stories, unlike the pretend stories about Sensory Processing Disorder, which regrettably too many people take seriously.