Motor Impairements and effect on communication

What are the motor impairments of children which impact ability to execute the motor skill of voice onset, phonation, and articulation in autism? How do we know this? What is an application of this knowledge to a direct clinical example?

Impact of Motor skills on communication in Autism:

Children with ASD struggle with varying degree of motor impairment that affect verbal communication in general and more specifically, articulation issues, voice onset and phonation skills. This blog considers describes some of these in detail.

Like two sides of a coin, Motor skills have motor planning to be considered as well as execution/motor control.

Motor planning is what our brain is doing before actual start of the action, its like setting up the GPS before hitting on the gas.

When verbally responding to a question, the final voice production to relay the thought must be first based on motor planning; information processing, creating the message or thought processing, body posture recognition and preparation, oral motor structure preparation (managing the chewing gum, finishing the swallow or may be taking a long breath etc), deciding the tone, pitch, volume, and much more.

ASD population has difficulty with most of these aspects, because they have atypical perception, communication receptive prosody issues and sensory integration deficits, all required elements upon witch motor planning will be based on.

This motor plan is then followed by the execution. This is when we step on the gas and drive on to destination, controlling the car.

One must be able to hold certain balance of facial, neck and head musculature when verbalizing. Motor control is essential to effective voice production, another weak link in children with autism.

Many ASD children have poor mid range control, or core strength for even basic proper body posture.

How do we know this?

Functional MRI studies demonstrate that there may be diffused and decreased cerebellar activation, and connectivity between regions of brain, the very basis for smoothness in movements. This impacts the voice onset, and phonation as well as articulation of speech.

A research study compared very young ASD children with similar age control group, and it was shown that preverbal children with autism demonstrated higher proportion of atypical vocal quality in syllables compared to control group. They did produce however similar number of vocalizations. [i]

In other words, children with ASD produced similar amount of vocalization, canonical babbling, although they produced significantly different sound, phonation component.[ii]

Clinical relevance and application

The knowledge and understanding in the workings of the brain of someone with ASD is expanding tremendously. Such knowledge can become the basis for treatment strategies sketched out daily in clinics.

A treatment plan to improve “sentence level answering” for example, can be based on all above discussed factors

- prepare the child posturally to successfully interact

- Consider visual/auditory processing, clarify directions

- Teach differentiation of pitch, volume, tone etc

- Work on breathing (really helps with long sentences)

- Short one time instructions

- Allow increased response/reaction time

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[i] Mostofsky, S. et. Al., Decreased connectivity and cerebellar activity in autism during motor task performance, Journal of Brain, volume 132, number 9, page 2413-2425, sept 2009

[ii] Stephen J. Sheinkopf, et al. Vocal atypicalities of preverbal autistic children, Journal of autism and developmental disorders, Volume 30, number 4, 2000.