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Hearing your little laugh is one of the best sounds in the world. But as well as being extremely infectious – did you know that their laughter is an interesting window into their development?
Dr Caspar Addyman from Goldsmiths, University of London is an expert on why babies laugh and author of The Laughing Baby.
At Goldsmiths' InfantLab, he leads an exciting branch of child development research designing laughter experiments, talking to parents around the world and even monitoring viral social media trends.
I’m fascinated by babies’ laughter because it gives us a glimpse into what they’re thinking and what they understand about their world.
He told us his favourite facts about babies’ laughter…
When do babies smile?
Often newborns will smile in their sleep.
You also might see your newborn’s mouth widening into a grin as they try to mimic your own facial expressions while awake.
However, this type of smiling isn't the type of smiling that adults do. Newborn babies do not smile in response to something that makes them happy.
It’s actually in the second month that you will likely see your baby’s first real smile. It's sometimes called a "social smile". This is a really important part of your baby's social and emotional development.
All babies develop at different paces, however, so it might happen a bit later.
In the newborn stage, looking at your face and making eye contact is one of the most important ways your baby can learn. So the best way to encourage your baby to smile is to chat to them and smile as much as possible.
By about 3 or 4 months old, you may find that your baby starts to smile at the sound of your familiar voice.
At what age do babies start laughing?
Babies start practising to laugh earlier than you probably think – in fact, researchers have even seen some babies smiling in the womb. In one survey, we asked parents when their baby first smiled or laughed and we found it happens from as young as three and a half months old.
Parents know their child best, including their expressions – they also told us that they can tell the difference between genuine baby smiles and trapped wind.
Babies don’t laugh at jokes, they laugh at people
Most of us think the starting point for laughing is a funny joke or action, but actually it’s a way of connecting to the people we’re with. Our sense of humour develops because of who’s around us and from their first laughs, babies are letting us know how they feel about us.
Babies can’t laugh on demand
Psychologists describe laughter as an ‘honest’ social signal, meaning it’s something we do spontaneously. Just like adults, when babies laugh it’s not a deliberate choice – the same goes for crying.
Although we don’t always know exactly what’s making them laugh, we do know that laughter means they’re enjoying themselves and want adults to continue whatever they’re doing.
Babies have playful moods
Research into what makes babies laugh can be tricky and my team are still learning lots about what’s really going on in babies’ brains.
We’ve found that tickling isn’t guaranteed to make babies laugh, which shows that they have to be in the right mood for playing and laughing, like adults. So don’t be downhearted if some of your usual jokes don’t always get a giggle.
Peekaboo is a global hit
We surveyed parents from over 40 countries and asked them what games their babies love to play most – everyone said their baby laughed and smiled when they play peekaboo together. It’s a simple game that’s fun and amazing for your baby’s development.
Tearing paper is a curious laughter trigger
In 2015, an unusual YouTube trend emerged when parents filmed their babies watching paper being ripped. Lots of families got involved and the results were the same – the babies loved it and found it really funny. But we’re not sure exactly why, so it’s something my team and I are looking into.
Laughter shows us babies understand something new
Researchers in Paris studied a group of babies being shown a toy duck to test the idea that they learn through copying other people. Half saw the toy being thrown on the floor and the rest didn’t.
The surprise result was that only the babies who giggled when the duck was thrown on the floor tried to copy the action when they held the toy. This means their laughter was a sign they understood they could copy the action.
Their laughter is a reward for you
There’s no such thing as a perfect parent and it can be a really demanding job. Laughter is one ‘trick’ babies and small children use to keep adults interested and engaged with them. They chuckle to show you how happy they are playing with you. And their laughter is so infectious it also helps you feel good and deeply connected to them.
Babies enjoy life
Babies laugh much more than adults do. One mum recorded over 500 separate laughs in one day from her twin boys and many parents have told us about hearing their children laugh in their sleep. This shows us, in very simple terms, that they are enjoying their life as a baby.
Let babies lead
Our research reveals that play and having fun with your baby isn’t as simple as showing them lots of brightly coloured games or toys. It’s best to let them show you what they’re most interested in and support them to discover what they like.
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