Down syndrome is a developmental condition. Children with Down syndrome are born with an extra copy of the 21st chromosome. Trisomy 21 results in multiple developmental delays.
Children with Down syndrome often have a learning disability. They develop speech and language skills much slower than neurotypical children. Their developmental delays become prominent by their first birthday.
The set of symptoms of each affected individual may be distinct. Despite varying rates of physical and mental development, every child with Down syndrome has a characteristic set of language and communication difficulties and strengths.
The development of speech and language skills is directly related to other skills of an individual. Therefore, speech therapy for children with Down syndrome plays a significant role in aiding their speech and language development.
What Influences The Speech and Language Skills of Children With Down Syndrome?
Let us understand how other skills of a child with Down syndrome influence their speech and language development and vice versa.
Hearing
A majority of all children with Down syndrome also experience hearing loss. The loss of hearing can affect one or both ears. The loss can be partial or complete.
There is a lack of sufficient longitudinal studies on the effect of OME in children with Down syndrome and its impacts on language delay.
However, present studies show that children with DS have narrow auditory canals. It may increase the risks of developing otitis media or infections of the middle ear.
Since children with DS are already susceptible to speech and language problems, middle ear infections with effusion (OME) present a higher risk of subsequent language delays resulting from hearing loss.
Oral-Motor Skills
Individuals with Down syndrome typically have a small oral cavity, narrow-high arched palate, and a large tongue. Doctors have noted significant differences in the musculature and innervation of facial structures in most cases as well.
These differences contribute to the atypical structure and function of the articulators. They reduce the intelligibility of speech, range of movement, and speed of the articulators.
Some children also bear the characteristics of childhood apraxia of speech (CAS).
Working with an SLP regularly can help a child gain better control over the movement of their articulator muscles. Moreover, an SLP can also teach the child and the parents several exercises that can make moving their lips, tongue, and jaws easier while speaking.
Cognition
Around 80% of all children with Down syndrome have low to moderate intellectual disability (ID). Very few have severe intellectual disability, while some may have IQ scores in the average range.
Individuals also experience impairment of visual long-term memory, visual object learning tasks, verbal short-term memory, and phonological memory skills.
Children and adolescents with Down syndrome may also have poor language comprehension, reading difficulty, and reduced mean length of utterance (MLU).
However, their receptive language skills are stronger than their expressive language skills. Therefore, working with an SLP can enhance their language comprehension skills. It can also teach them new methods of expression.
Language Skill Development – Areas That Require the Attention of SLPs
In toddlers with Down syndrome, expressive language skills are significantly less developed than receptive language skills. Speech-language pathologists can help children with DS improve their skills in the areas of phonology, syntax, vocabulary, and pragmatics.
Phonology
School-aged children with Down syndrome exhibit phonological errors similar to typically developing children. The inconsistency of the mistakes is the most noticeable trait of phonological disorders in Down syndrome.
It is proven that children with DS have poor speech intelligibility, which affects their expressive language skills.
Children with Down syndrome often exhibit poorer speech intelligibility as compared to typically developing children. Childhood apraxia of speech, dysarthria, and inconsistencies in voice quality are disorders that co-occur with Down syndrome further reducing speech intelligibility.
Speech-language therapists can help children with DS circumvent these challenges while speaking. Therapists can teach children to talk more efficiently and with less effort. Continued therapy can increase the intelligibility of a child’s speech.
Vocabulary
Studies regarding the vocabulary of children with Down syndrome have been conflicting so far. However, it is a proven fact that the acquisition of the first words of children with Down syndrome is delayed as compared to other children developing typically.
Some studies show that the vocabularies of teens with Down syndrome are somewhat similar to typically developing younger children. Moreover, children and teenagers with Down syndrome produce fewer words while speaking as compared to their typically developing peers.
Almost all collected evidence shows that the expressive vocabulary of children with Down syndrome is delayed relative to the neurotypical children of the same age.
Speech therapists can help children with Down syndrome learn new words, the meaning of these words, and apply them in expressive language.
Syntax
Children with DS have an underdeveloped syntax in both receptive and expressive language. By the age of 2-years, a child is typically able to put two words together and create small sentences.
However, children with Down syndrome take longer than typically growing children to put two words together and create a sentence.
Recent studies show that children with DS have a lower than average understanding of syntax as compared to their non-verbal cognition.
SLPs work on developing syntax and expressive language skills. Children with Down syndrome often show progress in strengthening reading & writing skills. However, SLPs can play a significant role in strengthening their reading and learning skills.
Complementing communication with visual cues (augmentative and alternative communication methods) can help children with DS develop their speech and language skills.
How Can an SLP Help a Child with Down Syndrome?
A speech-language pathologist or SLP can evaluate, assess and treat the speech and language difficulties kids with DS face.
One of their primary responsibilities is to develop a treatment plan following a comprehensive assessment. They can enlist the different areas that require work, such as receptive and expressive language, vocabulary, syntax (grammar), oral motor planning, and oral motor strengthening.
If your child has hearing issues, the SLP will recommend a qualified ENT (ear-nose-throat) specialist. Children with DS require frequent and regular hearing tests to rule out any hearing-related problems.
The SLPs can work with teachers, families, and children with Down syndrome to implement effective programs at home, school, and community levels. It can help affected children hone their communication skills.