Why your teen is hard wired to mumble

Mumbling and grunting teenagers are the butt of jokes. Overnight, it seems, many become monosyllabic once they hit puberty, transformed into the TV teen characters Kevin and Perry.

This can leave parents feeling exasperated, wondering where their chatty, friendly child has gone, and whether he or she will return.

but why does it happen? And is it cause for concern? The latter is not a flippant question as, for a very small minority of children and teenagers, mumbling will be a symptom of an underlying health problem such as hearing loss or a mental health problem such as psychosis.

That’s because psychosis affects the way the brain processes information, so that you hear and believe things that aren’t real, and people with the condition often mumble to themselves in response to voices in their heads, explains Dr genevieve von lob, a clinical psychologist in South-West london with more than ten years’ experience within nHS child and adolescent mental health services.

meanwhile, in teenagers with hearing loss, their perception of sound changes and they may be unable to hear their own voices clearly. This may encourage them to mumble — but they also might be unaware that they are mumbling, explains Dr von lob. These problems are, however, fortunately rare; for example, psychotic disorders affect 0.4 per cent of children aged between five and 18, according to figures from the Office for national Statistics.

but mumbling not due to a medical condition may be linked to a number of different factors.

Could gender differences be one? it’s well known, for example, that boys generally develop language skills later than girls.

This is thought to be due, in part, to a different wiring of the brain; more areas of girls’ brains, including the cerebral cortex (responsible for memory, attention, thought and language) are dedicated to verbal function, and the hippocampus — a region of the brain critical to verbal memory storage — develops earlier in girls. However, whether this is linked to mumbling is not clear.

but there is another possible gender link, with research suggesting that men are more likely to be mumblers because they have a smaller jaw opening.

ASTUDY, published in the Journal of Speech, language and Hearing Research in 2016, looked at the jaw opening angle and speech of 49 adult men and women. They found that women opened their jaws wider when they spoke.

As a result, their low vowel sounds, those produced with the tongue relatively flat and low in the mouth and which requires a wider opening of the jaw, were clearer.

yet men had a narrower jaw angle and were more likely to mumble these sounds. This could be because men have longer throats and larger tongues than women, which affect how wide they can open the jaw, the researchers said.

For most teenagers, however, mumbling is the result of the psychological, social, emotional and developmental changes that are going on in teenagers’ bodies and lives, prompted by profound hormonal changes, says Dr von lob.

‘The teenage years are a period of significant transition; they are neither children nor adults yet and it is very hard for teenagers to manage all these changes,’ Dr von lob, author of the book Happy Parent, Happy Child, told good Health.

‘mumbling is extremely common and normal and, for most teenagers, nothing to worry about — it is a developmental stage.’

in boys, it could be triggered when their voice breaks, and the embarrassment of their voice ‘cracking or squeaking’ when they speak, making them ‘more self-conscious and likely to mumble’, says Dr von lob.

A major factor is the developing prefrontal cortex in the brain, which controls attention span, impulses and emotional reactions — and is often blamed for the risk-taking and high emotions of teenagers and young adults.

‘The prefrontal cortex and the amygdala [ responsible for the expression of emotions] are still developing during the teenage years and this means they often have heightened emotional responses and their moods can change quickly, which they find difficult to manage, so mumbling might be part of that,’ says Dr von lob.

‘They may not want to be heard because they feel self- conscious and lacking in confidence, and often are not even aware how much they are mumbling.’

Another key role of adolescence is separating from parents in order to become independent.

‘many teenagers want more privacy so they become monosyllabic or prefer to text rather than talk as a way of trying to become more autonomous and independent,’ adds Dr von lob. ‘This is normal and perfectly healthy.’

As to how to deal with a mumbling teen, Dr von lob recommends ignoring it where possible.

‘A mumbling teenager can be frustrating for parents,’ she says. ‘However, it is normal so try not to take it personally and ignore it rather than confront them about it.

‘Once a teenager has found their independence, sense of self and identity, you will develop a different relationship with them and they are likely to become chattier.’

if you do need to talk to a grunting teen, find a good time for them.

‘Walks and car journeys can make the process easier because they feel less self-conscious and there is less pressure than sitting face to face,’ she adds.