Friday, January 1, 2010

Sensory Processing and the Autistic Child

Interestingly, the DSM-IV definition of autism never mentions "sensory processing dysfunction" as a condition for autism.  But almost all children on the autistic spectrum seem to have problems with their sensory processing.  As a parent of a child on the spectrum, it's important to be aware of your child's sensory dysfunction and his or her triggers.  Most children are either over-stimulated or under-stimulated in a particular sense.  The best part of this is that this can flip-flop at a moment's notice and lead to a "meltdown".  What's a meltdown?  Is it like a tantrum?  Many people look at Alanna (who is 25 months old) and think her meltdowns are tantrums.  After all, she is 2.  But there are important differences between the two:

  • A tantrum is usually caused by a denied request for something Alanna wants.  She cries and gets upset, but the cause is generally clear and the tantrum eventually eases.
  • A meltdown is almost always caused by sensory over-stimulation.  Usually these are sudden occurrences that seem to have sensory stimulus (e.g. bright lights, loud noises, sudden odours) and continue to escalate until the stimulus can be removed.  In many cases, we do not know the cause of the meltdown and it's only resolved by moving her to a new location (usually going home or at least getting in the car).  A meltdown is not my toddler expressing that she is not having her way - she is expressing her discomfort and pain the only way she knows how.  I try to think of it like this:  if she is bothered by lights and the meltdown ceases when I turn them off, how would I feel if my normal lighting was 100 times brighter?  Eventually it would overload me and I would probably close my eyes with my face in the floor.   
Every sense can be impacted, even some you probably don't even know you have:

Does your child enjoy looking at lights?  Do visually stimulating books and toys capture their attention?  Did your child spend a lot of time staring at your Christmas tree?  If so, then your child is probably under-sensitive visually and seeks visual stimulation.  Other signs include staring at objects at weird angles (Alanna often stares at objects very close up or upside-down), wiggling hands in front of one's face, or short jerky head movements.  Alanna does all of these things.

On the other hand, if your child squints their eyes in normal light, enjoys dark rooms, avoids sunlight or becomes agitated with visual stimulation (think lots of lights and colours and movement), then they are potentially over-stimulated.  Alanna varies between the two - she is generally under-stimulated but can become over-simulated very easily.  Turning off the lights helps restore order.  Some days an exit sign can be very scary; other days it's funny and it's worth laughing at.

Most autistic children are under-stimulated by sounds.  They do not respond well initially to aural stimuli.  Most autistic children have to be taught to respond to their names or notice when a noise is occurring in their environment.  Alanna has slept through a smoke detector going off right outside her door for several minutes.  Not a peep.

On the other hand, some children may be sensitive to certain noises.  Alanna has always hated clanking cutlery.  She usually cries and puts her hands over her ears to tell us this noise bothers her.

The sense of smell is sense where we've been lucky.  Alanna seems to have a mostly normal sense.  Most odours don't bother her and yet she doesn't seek it out by smelling everything or smearing her feces on the wall to get a good whiff.

Many autistic children are picky eaters.  Alanna is over-stimulated and is very sensitive to many foods, including any vegetables because they tend to be bitter.  Other children may be under-sensitive and mouth or lick inedible objects or eat dirt (pica) to stimulate their sense of taste.


Alanna craves touch.  She loves deep pressure and seeks it out by rubbing her body with objects one would normally find uncomfortable. She also loves enclosed spaces (such as between furniture and the wall) because it simulates her sense of touch.

On the other hand, she is very sensitive to certain textures which does not help her picky eating.  Many other autistic children are over-sensitive to touch and resist hugs, affection and being touched in any way.  Such children also tend to hate clothing and have to learn how to wear clothes without being bothered by the sensation.

Children who are under-stimulated by movement crave it.  They'll run around all over the place, enjoy bouncing, jumping, climbing.  Alanna's sense of movement is very under-stimulated.  I could put her on a roller coaster that would scare me and she would probably enjoy it.  She loves vestibular games like "airplane".

Over-stimulated children may not like fast movement.  They may be afraid of escalators and dislike vestibular games where their bodies are moving around quickly.

This sense is an odd one because most people don't think about it, but it's really important.  It essentially tells us where our body is in space.  Without it, we have difficulty with balance and motor planning.  As is typical with many autistic children Alanna is clumsy and struggles with complex motor movements.  Motor planning is the ability to plan and carry out a skilled, non-habitual motor act in the correct sequence from beginning to end. Incoming sensory stimuli must be correctly organized to result in an appropriate, coordinated motor response. The ability to motor plan is a learned ability which can be generalized to all unfamiliar tasks so that the child does not need to consciously figure out each new task he faces. A child with motor planning problems may be slow in carrying out verbal instructions and often appears clumsy in new tasks.

How do you deal with sensory issues as a parent?  I'll get back to you on this one.  We are engaging with an Occupational Therapist for help here, but unfortunately their are no private therapists in this region (public therapists come with - you guessed it - waiting lists) and we have to commute to find this help.  Our therapist is at Blue Balloon in Burlington.

Our latest issue is the bath.  For several weeks Alanna will love her bath, and then hate it for several weeks.  We're in a hate period.  She has a complete meltdown in the bath, but it's not optional so we endure it.  I suspect it has to do with the feeling of water on her skin but I'm not sure.  She knows the word "bath" and will start crying if you tell her it's time for one, then look at the water pouring into the tub and run out screaming like you're about to give her a root canal without anesthetic.  It's heart wrenching.  But she needs to be clean.


  1. Your posts are amazing. So informative and well-written. I knew a little bit about sensory issues before, but I have never seen it all presented so clearly. Alanna is very lucky to have parents that "get" her.

  2. love your blog bec, too bad lana is in a hating mode for baths , a clt i had did not like baths either, not sure if it was the temperature or what, hope she goes into like mode soon

  3. My son who is 2 was just diagnosed with having high functioning autism. I found your blog while googling info on his sensory issues and I just wanted to let you know that I thought it was really great! We're in a very similar place as you guys. JD just started ABA two weeks ago and we are already seeing a lot of progress from practicing mands! Keep up the great inspirational writing!

  4. Hi there- I also have a daughter who was diagnosed just before her second birthday with autism. Have you tried the GFCF diet? Has it been successful? We have been on for approx. 6 months but really don't notice any difference and now are struggling to remain on this restrictive diet if it truly provides no benefit...any comments would be most welcomed.

  5. wow, what a discovery, thanks for all you share. Im a single mum of a 9 year old boy with asperger's and an almost 5 year old without. I AM sorry I hate asps some day's. But it's great to know I'm not alone, thanks to people like you, and it can always be worse. I wouldn't change Him for thee world.