Wednesday, October 6, 2010

Auditory Defensiveness

How do you know if your child is auditory defensive?

If your very young child is acting up or being consistently disorganized in a noisy classroom {or trying to escape by hyperfocusing on books or otherwise tuning out and refusing to participate in class} the chances are very good that he is sensitive to noise and is seeking a way to escape.

Auditory defensiveness is a clinical condition in which the child is highly sensitive to sound.  This means that sounds, noises, and voices that would not register at all, or would not be perceived as irritating to a normally functioning nervous system, are perceived as too loud, too high pitched, or otherwise difficult to tolerate, and so he must defend himself against them.  The child will do this by tuning out,  hyperfocusing on something else, holding his hands over his ears, attempting to escape the situation in which he finds himself by running away, or by acting out in such a way that the adults are left no choice but to remove him.

 Or the child might have such sensitive hearing that his nervous system will not only hear, but then alert him to things that other people don't notice.  These are the children who are constantly asking, "Did you hear that?  What's that noise?  Who's talking?" when you don't hear anything at all.  They are pulled out of their ability to attend by the sounds we hear but don't really register, such as traffic, people walking in the hallway, sirens, a telephone ringing in the next apartment, the sounds of plumbing, or the refrigerator fan.  Their ears simply do not habituate to any of it.  They are alerted again and again to noises that a normally functioning nervous system would recognize as irrelevant and filter out, and responding to them as if those things were a cause for alarm.  In the clinic where I treat, if one of my colleagues turns on the answering machine to listen to her messages or returns a phone call at her desk, all activity at the table will often come to a complete halt as the child becomes unable to focus due to the new, distracting stimulus.  Or when the reception area gets noisy, as it will in the afternoon,  an auditory defensive  child  will suddenly become completely disorganized, running around aimlessly or even wandering off altogether instead of participating in the game we have been playing.

I once had a child in my practice who was so sensitive to sound that if someone rang the doorbell while he was working on the suspended equipment, it would cause him to startle so intensely that he would lose his balance and fall.

It's tough to navigate school when your hearing is so sensitive.  The sounds of the bells and buzzers, lockers slamming, children shouting, the echoing noise of the bathrooms and the gym, the chaos of the playground and the cafeteria  -- all these things are experienced as an assault, and will put a child whose hearing is ultra sensitive on high alert and force him to stay there.  This limits his availability to learn, socialize, explore, and develop.   Unfortunately, one of the most common types of auditory defensiveness is sensitivity to high pitched sound.  In a primary school, that's all you hear all day long: the sound of women's and children's voices.  The problem can be so extreme that the child's receptive language is delayed as a result of tuning out voices all the time.

Another feature of auditory defensiveness is the inability to filter out background noise and concentrate on what is relevant.  An adult client who recently came for help told me that he habitually avoids restaurants, parties, and other social situations because his ears simply can't separate out voices from the background noise, and it's too difficult to hold a conversation.  The only time he can socialize comfortably is when he is interacting one on one in a quiet room.

There are a number of possible reasons for auditory defensiveness.  If the child has a history of ear infections, it could be that the infections have compromised the workings of the bones in the middle ear by leaving behind a sticky residue of pus.  These bones vibrate in response to sound and regulate the pressure in the inner ear.  If they are not responding appropriately, pressure in the ear builds up and it becomes painful.

In some cases, the muscles in the ears, which are responsible for dampening sound, are not doing their job properly.  Children who have low oral motor tone {which manifests itself as mushy, lisping speech or problems chewing food} often have this problem.

In the sensory gym, we treat auditory defensiveness in several different ways: directly, through the treatments we offer, and indirectly, by teaching the child and his caretakers strategies to compensate for his inability to filter and dampen sound.

When the child participates in high intensity vestibular activities, such as spinning, it works on the structure of the inner ear, which helps to normalize the way the child takes in sound.  So does the specially filtered music that many therapists have been trained to prescribe.  The vibrations through the bones in the skull and ear that are transmitted by the headphones can actually loosen up the internal structures that have become immobile due to ear infections.

Chewing can help a child dampen sound.  Gum is very good, if your child's teeth permit.  I would strongly advise you not to supply gum with artificial sweeteners.  Stick with regular, or use xylitol sweetened gum.  {Check those labels  -- I no longer chew Juicy Fruit or Bubblicious or give them to the children in the clinic, since even though they are not marketed as sugarless, they now contain aspartame.  Peelu and Glee gum are both Feingold approved.}

You can also give him non food things, which probably his teachers would prefer for classroom use.  I use clear plastic fish tank tubing from the pet store, which is very discreet, or you can buy small dog chew toys, which are designed to withstand merciless chewing.  There are therapy chew toys, of course, but they are expensive.

If the problem is extreme, you can try a set of inexpensive earplugs, which dampen sound but allow voices to come through.  I buy them in packs of several dozen for about three dollars and wear them on the New York subways and in movie theaters, which are always too loud for my liking.  Your child may like to  use these at family gatherings or other noisy venues.  If your child is historically difficult at these types of events, talk to his occupational therapist for strategies to help him manage, or limit your time to what he can tolerate.

Sometimes manual therapy can be exceedingly helpful in helping a child with sensory processing issues. If you are lucky enough to live in a city with a Canadian or British trained osteopath, who specializes in cranial osteopathy, you may want to give it a try.  Here in New York, I refer many of the children I treat to a Canadian trained osteopath, and she has been a tremendous help to almost all of them.  For a wonderful introduction to the powers of osteopathy, and a lovely portrait of the late osteopathic practitioner Robert Fulford, I recommend Andrew Weil's book Spontaneous Healing.

3 comments:

Twocuphabit said...

Thank you, thank you, for this post. Google kindly directed me here. ;) This is a great intro - it verifies that my kiddo has a "real" problem.

Heather Sharp said...

Great post, thanks. I'm subscribing!

Anonymous said...

Excellent, clear, and thorough explanation of what my son has. THANK YOU! Helps a lot!