Why routine screening of children's hearing could help to prevent a range of later difficulties

According to news reported today (BBC website 26.01.26)

 “Tens of thousands of children in England have spent more than a year waiting for NHS community care such as hearing services, speech and language therapy and disability support, the BBC has found. The analysis shows a quarter of the 300,000 children on waiting lists have been waiting more than 12 months.”

While doctors recognise that these delays are catastrophic in the the potential impact on children’s development, there is generally a poor understanding of why this is the case. Hearing provides just one example of the importance of early detection and treatment

Infants are born with an innate capacity to learn any language under the sun provided they are exposed to the sounds of that language on a daily basis in the first three years of life continuing up to six years of age.  

Every spoken language comprises a unique range and combination of sound frequencies that constitute what we later recognise as being letter and word forms.  During these years, an infant must learn to tune-in to the frequencies that are specific to its mother-tongue.  While the occasional ear, nose and throat (ENT) infection is common in the pre-school years, frequent or prolonged periods of infection, glue ear or abnormally enlarged tonsils or adenoids can affect a child’s ability to hear, discriminate and repeat specific sound frequencies.

In the English language high frequency sounds are particularly important to be able to distinguish between sounds such as s and f,  f and th, sh and ch for example.  Nasal congestion can result in difficulty hearing the difference between m and n.    Even mild hearing impairment can affect a young child’s ability to hear speech sounds clearly.

Mild to moderate hearing impairment can persist for up to six weeks after the acute phase of infection has passed.  Children who suffer from recurrent ENT infections (three or more in a single year) may therefore experience mild to moderate hearing loss for nearly six months of the year during the crucial developmental period when the brain is learning to distinguish between similar speech sounds.

The effects of mild to moderate hearing loss on children can also be behavioural and may be observed in two aspects of language – receptive and expressive.

Signs of symptoms of hearing deficit on receptive language, which is directed outward, can include: short attention span; distractibility, mis-hearing; mis-interpretation of speech; confusion of similar sounding words; need for frequent repetition or high volume on television or computer games and paradoxically, over-sensitivity to certain sounds.

Signs of issues with expressive listening (directed within and involved in control and modulation of the voice), may include: flat and monotonous voice; loud voice; hesitant speech; weak vocabulary; confusion, reversal or substitution of letter sounds, poor reading comprehension and inability to sing in tune.

Any of the above can affect a child’s ability to interact socially and increase levels of frustration manifesting as: low tolerance for frustration; difficulty making friends resulting in a tendency to withdraw or avoid social situations and low motivation or interest in class.

General aspects of development may also be affected.  Nasal congestion can affect breathing, particularly during sleep affecting quality of sleep (growth hormone is secreted during sleep), daytime attention, and in some cases may contribute to prolonged bed wetting.  Children may select and insist on eating a restricted range of foods because between 75% and 95% of perception of taste is based on the sense of smell leaving the tongue to detect only basic tastes like sweet, sour, salty, bitter, and flavour. These children will tend to seek out strong tongue tastes and textures that do not require much chewing.

In pre-school children, the biggest impact can be on speech development.   Speech acts as a foundational pillar for cognitive, social and emotional growth preparing them for literacy and school success.  Verbal interaction is vital because it builds a vocabulary that grows from roughly 1000 words at age three to 10 000 by age five and speech sounds provide the foundation for recognition of written symbols on a page.

Despite all of this, children often have to wait up to or in excess of twelve months from referral to being seen in the NHS.  If an initial hearing assessment indicates hearing loss, they may be advised to return a few months later (spring or summer), when it will appear to have improved, only for symptoms to return in the autumn following discharge.  Developmentally this “lost” time cannot easily be made up.  Over many years of assessing children’s listening skills at a later age, I have observed even though their hearing may be normal, their ability to discriminate and process sounds has been affected.  In other words, although the ears can hear, pathways between the ears and the brain normally developed during the critical period for learning language, remain under-developed with effect on reading, spelling, spatial awareness, social skills and self-image.

Delays in treatment and referral for active speech therapy (versus only assessment) also delay the process of ensuring that young children develop  the listening and language skills they need to support all aspects of life and learning.

We recognise how hearing loss can lead to irritability, social isolation, difficulty coping with background noise and contribute to symptoms of dementia in the elderly, while the long-term impact of mild or intermittent hearing loss on children of today, is largely unknown.

While the NHS is currently struggling with existing referrals, a long term plan to implement a national programme of screening children’s motor, hearing and visual skills in the pre-school years could do much to prevent the later onset of many later educational and behavioural difficulties.