From 'goo' to 'go': baby's language development

From "goo" to "go", language development can be both a subject of fascinating conversation and a topic of concern, as Dr Anne Tait describes. 

It’s quite remarkable to think that babies are born with crying as their only form of vocalisation, yet within a relatively short amount of time they'll be chatting with you about the colour of the sky, the weather, the bedtime story, the menu...

As with other aspects of a child’s development, when it comes to communication, a lot goes on within a short space of time. During the first three years of life, there is an exponential increase in brain cells. These cells are rapidly forming connections with each other, which is fundamental to the progression from crying to conversation.

Development is a complex interaction between biology and environment. A baby’s brain develops based on the experiences it is exposed to. Babies need their primary caregivers to be in tune with and responsive to their needs, and emotionally connected. This is the foundation for ongoing development – language development in particular. Right from birth it is important that children are exposed to a language-rich environment through interaction with their family to help build their communication skills. If a baby’s brain is not exposed to lots of language coming from the caregivers they love, then it is hard for the brain to build those skills. Communication is a two-way street, with the baby and caregiver communicating back and forth through eye contact, smiling, cooing, babbling and talking. This is the basis for normal language development in neurotypical children.

Straight talking
Typically it's good to have an understanding of what ‘normal’ is, to help determine when things are not progressing as expected. Language development involves expressive (spoken) and receptive (understood) language. This table shows normal, but significant, milestones. The timings are approximate.

We should never underestimate the communication ability of a new baby. Newborns are hard-wired to start communicating from birth, through different types of crying sounds, eye contact and awareness of the sounds around them, in order to build a bond with their parents. Their bond starts with eye contact and builds with smiling, cooing, babbling and laughing. The development of their first words takes place by approximately 12 months of age. In general, this standardised process occurs in children of all cultures. In most children it seems almost effortless, but if communication doesn’t develop as expected, then it is important to determine the reason why. 

Talking to the doctor
As with gross and fine motor development, language is not a smooth trajectory and there can be some fits and starts, but the overall progression is forward. Once a child has a 50-word vocabulary, there is a rapid exponential increase in their language skills.

If a parent has concerns about their child’s language development, the first point of contact can be their Well Child nurse or family doctor. After a review of the child’s overall development, the usual pathway (if there are concerns) is referral to a paediatrician or speech-language therapist for further assessment.

I am not a trained speech-language therapist. As a general paediatrician my role is to look for and address any medical cause for a child’s language delay through reviewing other aspects of their development and looking at any other health issues that could be contributing to language delay. My approach is to take a comprehensive medical history, observe the child’s communication in clinic and examine them to see how they communicate with a stranger (ie me).

I want to know what the parents’ concerns are, and I then go through a systematic approach to outline the child’s language development to date. This includes questions about when they used their first identifiable words, how many words they can say at present, their understanding of language and their progress over time. It is always important to know if there has been any regression of language.

Other important factors to review include non-verbal language skills, such as eye contact, facial and other gestures, pointing, giving and showing, and how a child indicates their wants; whether a child likes to include their parents/caregivers in play and activities; what things a child likes to play with; and how they play and interact with other children. In addition, a thorough examination is mandatory to check for any clues to a medical diagnosis, as is review of other developmental skills and a child’s past history.

Red flags
The following ‘red flags' trigger the need for more in-depth assessment:

■   Reduced eye contact
■   No pointing by 12 months of age
■   No words by 18 months of age
■   Less than 50 words by 24 months of age
■   Language regression
■   Caregiver concerns about hearing

Why the delay?
Thirteen to eighteen percent of 18-36 month olds have some expressive language delay, with 50% of these still having language difficulties by four years of age. Difficulties with language may affect schooling and behaviour later on so early detection and intervention is key. The causes of language delay are many and varied, but some typical diagnoses I see in my clinic include:

Hearing impairment
For any child with language development concerns, it is vital that their ears are examined and their hearing checked by an audiologist. If a child has chronic glue ear, and/or other forms of hearing impairment, this will greatly affect their ability to learn language. However, it is important to note that their non-verbal language should still be normal, even with hearing impairment. 

Isolated expressive language delay
This is where children have normal understanding of language and non-verbal communication, normal play, and the rest of their development and examination is normal, but they have a delay in their spoken language. This is what we call a diagnosis of exclusion, meaning that other causes need to be excluded first. This may be due to an underlying language disorder, or not being exposed to enough child-directed language in their environment. For some children, the difference between being in a low socio-economic group as opposed to a high one can be the exposure of around 62,000 words compared to 215,000 words within one week alone – which can later equate to a difference of up to 30 million words by three years of age. This difference can be apparent from as young as 18 months of age, according to a recent Stanford study by Anne Fernald et al. This can lead to some children being up to two years behind their five-year-old peers when they start school.

It is important to know that children learn language from real humans, not the electronic ones. As previously stated, language is not just about talking, but social interaction, love, shared bonds and non-verbal communication, which a child cannot get from electronic devices – even the ones that talk.

Specific language impairment
These are most likely due to a biologically-based neuro-developmental disorder, rather than lack of exposure to language. This diagnosis is made by a speech language therapist using various assessment tools. There are a number of different terms for these conditions, and ‘specific language impairment’ is an umbrella term. Some children get a diagnosis of oromotor dyspraxia, where they have difficulty with the motor movements used for speech. Usually this presents with pronunciation difficulties rather than delay.

Learning difficulties, intellectual disability and genetic syndromes
These learning delays can manifest initially as language delay, although sometimes won’t be apparent till some years down the track. There may be difficulties with gross and/or fine motor development, but not always. Generally speaking, the learning difficulties become apparent in school. There are many syndromes that can present with delayed language development, and these are usually associated with specific facial features, hence assessment by a paediatrician is needed to actively consider these possibilities.

Autistic spectrum disorder (ASD)
This is the main diagnostic category paediatricians are actively screening for, apart from hearing impairment. ASD is a developmental disorder where a child’s communication skills, social interaction and behaviour differ significantly from neurotypical children. This is because of a presumed underlying complex genetic cause affecting early brain development in the embryonic period. It is not due to failure to bond or to speak to the baby early on. ASD is something parents today are more aware of than previous generations and is really a whole topic in itself. It can first present with language delay, but enquiry by an experienced practitioner reveals impairments in social interaction which might not be obvious to others, especially in very young children. When ASD is suspected, there may be a need to do a specific play assessment and observation in early childhood education centres, if the child attends one. The diagnosis of ASD should be made by an experienced professional, who then can refer the child and their family to specialist services for treatment. 

In conclusion, it's important to note that the following conditions do not cause language delay:

■   Growing up in a bilingual or multilingual household. In fact, the more language a child is exposed to, the better.
■   Stuttering. Most preschool children go through a stage of developmental dysfluency (repeating words and phrases). This usually resolves within a few months. Non-developmental dysfluency (stuttering) does not resolve on its own and requires speech therapy, but does not cause language delay per se.
■   Being a boy. Parents tell me they're concerned about their son’s speech but have been told that "boys are often behind". This needs discrediting. If a parent is concerned about their child’s language development, gender should not come into it.
■   Other children communicating for them. That might well be true on occasion, but siblings should expose a child to more language.
■   The child is too lazy. Parents often tell me that they've heard this misguided theory. No child is ever too lazy to talk. Children are hard-wired to want to talk and communicate. 

Dr Anne Tait is a general paediatrician employed at Starship Children’s Hospital who also works in private practice at Auckland Medical Specialists. She has an interest in all areas of children’s health and wellbeing.