There is no doubt that the Picture Exchange Communication System (PECS) system is very efficient. It allows the child to communicate a need and understand the adult’s request, and consequently reduces the frustration of both people.
However, when the child is not deaf, we recommend that any replacement for complex verbal communication should be a temporary approach. This article aims to present some of the research foundation for our recommendation.
There can be many reasons why a person is not able to enunciate, ranging from an impairment of the cranial nerves or vagal system, to cortical damage, or damage to the auditory receptors to name only a few. Mendability’s goal is to help the child to express their needs and emotions vocally by repairing the damaged brain functions.
The PECS system was officially introduced as a tool in speech therapy at the end of 2000. It has great value but can only be considered as a temporary measure because of its inherent risks.
The brain of a child with speech delay is different in morphology, organization and level of activity from the brain of a child with no speech delay. This was discovered in the first ever study of speech delay using fMRI conducted by Dr Atman (2003) at the Chicago Hospital. He concludes:
Speech-delayed children aged 4 years and older demonstrated a statistically significant increase in right temporal dominance activation, compared with controls (44% vs. 86%). (To be noted here that speech is dominantly processed on the left side of the brain).
Those children also had a statistically significant decrease in total brain activation, compared with controls (46% vs. 82%).
Based on these findings, we can expect that children with speech delay will not be able to access naturally and develop their speech areas, which will lead to a constantly increasing deficit unless the initial damage is mended.
Some technical details about where speech is formulated in the brain:
- Before any words are actually spoken, vocal communication in sentences or using a group of words is processed by seven distributed regions of the brain correlated with speech and speech complexity, including five left-sided areas, one middle-frontal gyrus, and two right-sided areas.
- Before enunciation, the association of a visual representation to a group of sounds learned by repetition will involve one central gyrus, one left- and one right-sided posterior brain area, and one right-sided area.
Experience and repetition will install new connections.
Any protocol that is used on a long-term basis and is designed to promote communication outside of the pre-designed brain areas will draw a new speech brain map and install connections which will be very difficult to modify, simply because it serves a purpose and is easy.
A child’s brain grows according to experience, environmental demands and also according to the child’s own genetic makeup. Some of the most crucial developments need to happen in sequence in order to support the development of other crucial zones. In neurophysiology these sequences are referred to as “critical times”.
Here is an example of a critical time, from a study in the field of neuroplasticity. This study related to vision but applies to any crucial sensory processing. In this experiment (J Comp Neurol. 1982 ), kittens were set in a device that allowed no head movement, and they were placed facing a screen with vertical black and white lines. The exposure lasted only a few days, while the kittens were receiving all other appropriate care. At the end of the experiment, the kittens were set free and it was observed that they had become blind to anything which was not a straight vertical line. This deficit could not be reversed at the time.
A considerable amount of research has been done to evaluate the impact of early experience on the shape and organization of the brain. Over 80 years of research confirm that experience will define the brain.
Should PECS become the child’s natural communication tool?
Using a novel communication mode such as pictures is undeniably efficient in helping a child learn how to communicate. This picture method will become his or her “natural” communication system, as the brain will adapt to this new method.
Speech production is one of the most complex and rapid motor behaviors. It involves a precise coordination of more than 100 laryngeal, orofacial, and respiratory muscles. Vocal communication in sentences also requires the involvement of complex facial movements tightly connected to the execution of many important functions such as chewing and swallowing.
Limiting verbal communication to the exchange of a visual input on a small picture, even when it is accompanied by the enunciation of the label, is building a gradual limitation to all those crucial functions of speech.
The brain has one permanent priority which is to preserve energy. If one input can be translated or processed in two different ways, the brain will favor the option that consumes the least energy. Once a person has organized and memorized a set of pictures, these will be the preferred modality for the brain as this system requires, as we have seen, much less energy.
Deprivation of complex organization at any stage of development will induce physiological and structural changes that will modify the circuitry of all the brain’s sensory and cognition systems.
A lower demand on the brain, in such delicate and sophisticated areas as those involved in speech may lead to a decrease in the number of connections and even a decrease in size of the speech areas.
Mendability’s Sensory Enrichment Therapy includes exercises that are designed to target speech development. For more information about the program, please visit www.mendability.com.
Some extra reading:
Below is a very small portion of the scientific bibliography supporting this article.
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Brain. 2009 Jul;132(Pt 7):1918-27. Epub 2009 Jun 4.
Neural processing of spoken words in specific language impairment and dyslexia.
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