Q: Jessica is 26 months old and has a diagnosis of autism/PDD. She has started to respond to discrete trial instruction, however she presents with constant mouthing, licking, and biting her fingers. We have tried numerous things – chewing tubes, cold stimulation, vibration to the mouth, pressure, sweet, sour, salty, ignoring, and so forth. But the behaviors are increasing. Parents report constant licking and gnawing at furniture, books, and other household objects. Any suggestions you can give that might help would be greatly appreciated.

My clinical experience has taught me that a child on the autism spectrum usually is mouthing for a different reason than is a child with an oral motor dysfunction related to a motor speech disorder (apraxia, dysarthria). Therefore the solution is completely different.

Children with motor disabilities, like apraxia or dysarthria, may need to increase mouthing behavior in order to learn about the oral mechanism. Learning more about the mouth helps these children discover the oral movements they need for phoneme production and feeding skill.

But children on the autism spectrum often are using mouthing for a different reason. My clinical experience has taught me that these children are not using mouthing to learn about the mouth. They are mouthing to regulate their behavior. Children on the autism spectrum often use mouthing the same way they use hand flapping, finger twisting, rocking, and other forms of sensory self-regulation. These behaviors help them take control of their uncontrolled sensory responses.

As you have noticed, your inclusion of mouthing techniques appropriate for children with a motor speech disorder has not helped. In fact, it has worked in the opposite direction. It has caused an increase in the undesirable behaviors. That’s what mouthing activities are designed to do. Mouthing activities are used to increase mouthing behavior for a while. They are used to get a child more interested in his mouth, to play with his mouth, to initiate more movements with his mouth, and to discover what his jaw, lips, and tongue can do. That knowledge then is carried into the process of speech or feeding therapy.

A child who is using mouthing behavior to regulate his sensory system, and who is developing oral habits like the ones you describe, however, needs a program to help him regulate, control, and eventually eliminate his oral behaviors. Adding more mouthing experiences to his routine will not help him do that, as you have discovered.

Children on the autism spectrum often need a program of behavior management designed to regulate, control, and eventually to eliminate their developing oral habits. The principles and methods of this work are the same as any used to change a child’s unwanted behavior. The methods used to eliminate oral habits are the ones I would select, adopt, and experiment with were this child on my caseload.

My little book How to Stop Thumbsucking addresses this issue. Although it was written with the average-little-kid-who-sucks-his-thumb in mind, the principles and methods explained in the book should help you begin to formulate a different plan for your client with PDD. You need to begin to think about inhibition procedures, not facilitation procedures.