I'm Sam.

And I'm Neil.

Have you heard this joke, Neil?

Question: what's a rat's favourite game?

I don't know, Sam, what is a rat's favourite game?

Hide and squeak!

Ha-ha-ha! Very funny!

Well, I'm glad you're laughing because, as we'll be finding out in this programme, laughter is good for you! In fact, laughter is often called 'the best medicine'.

And it seems that's really true, medically speaking. Laughing releases anti-stress endorphins into the body and there's evidence that people who laugh recover more quickly from illness, including Covid.

Laughing is an essential part of what makes us human.

Babies cry straight from birth but the next sound they make, often as young as two or three months, is laughter.

And who can hear a baby

laugh without laughing

themselves? Laughter

is catching.

But before we start tickling

our funny bones, I have

a quiz question for you,

Neil, and it's no laughing

matter. Laughter can be a

serious business. In fact,

there's a scientific field

of study into laughter and

its effects on the

human body. But what is this

study called? Is it:

a) gigglology? b) gelotology?

or c) guffology?

Did you make those words up,

Sam? They sound a bit funny

to me! I'll say the study

of laughter is

called b) gelotology.

OK, Neil, but you'll be

laughing on the other side

of your face if you're wrong!

Anyway, we'll find out the

correct answer later

in the programme.

Someone who's an expert

in the study of laughing -

whatever it's called - is

cognitive neuroscientist,

Professor Sophie Scott.

Here she explains to

David Edmonds, presenter

of BBC World Service

programme, The Big Idea,

exactly how a laugh

is produced.

Laughing is a variation

of breathing. Like

breathing, it involves

the rib cage.

When you laugh you get

these very, very large,

very fast contractions of

the rib cage. And it's a

very primitive way of

making a sound, so

you're really just

squeezing air out in

big bouts. Each of

those individual

squeezes gives you

a 'ha!' sound.

The 'ha-ha' sound

you make when you

laugh comes from

your rib cage - a

structure made of bones,

called ribs, inside your

chest which protects

the heart and lungs.

The rib cage works like

a drum to amplify a laugh.

It's the reason why

jokes are sometimes

called 'rib-ticklers'.

Professor Scott calls

this a very primitive

way of making sounds

because it's simple,

natural and

essentially human.

The word primitive can

be used to describe

anything relating to

the basic way humans

lived in their early

stages of development,

before money, machines

or writing were invented.

Primitive human noises,

like crying and laughing,

link to a universal human

experience, and this can

be seen in the large

number of words we use

to talk about them.

In English, 'chuckle',

'giggle', 'chortle',

'cackle' and 'guffaw'

all describe different

types of laughter.

Right, so how would

you describe a

'giggle', Sam?

I'd say a giggle is

laughing in a quiet but

uncontrolled way, like a

child who finds something

very funny or

feels embarrassed.

Unlike a guffaw which

is when you blast out

a very loud laugh, often

at something stupid or

rude someone has said.

But humans aren't

the only animals to

laugh. We belong to

the same family as

other primates like

chimpanzees, gorillas

and orangutans, all

of whom laugh.

Even rats tickle each

other and make squeaky

noises like laughter when

they play. Here's

Professor Scott again

to take up the story for

BBC World Service programme,

The Big Idea.

Play is a very important

behaviour for mammals - all

mammals play when they're

juveniles and some mammals

play their whole lives,

and laughter is a sort

of an invitation to play,

it s a sign that

you re playing.

Professor Scott says

that laughter is an

important social tool

for all mammals - animals,

including humans, dogs

and whales, which give

birth to live young,

rather than laying

eggs, and who feed

their young with milk.

By laughing, young

mammals - sometimes

called juveniles - signal

that they want to play,

and young rats who don't

laugh back are more

likely to get a bite

than a giggle. And a

rat bite is nothing

to laugh about.

What a lot of facts

we've learned about

laughter, Neil!

Yes, we could almost

be experts on

laughter... 'Guffologists',

isn't that what you

called them, Sam?

Ah yes, in my quiz

question I asked you

to name the scientific

study of laughter and

its effects on the body.

I'm almost certain it's

not 'gigglology' or

'guffology'! So, the

answer must be...

Gelotology! The

correct answer!

Well done, Neil, I knew

you were good for a laugh!

OK. Let's recap the

vocabulary from the

programme before you

think up any more terrible

jokes! First, we had

rib cage - the structure in

your chest which is made

of ribs, and produces the

sound of a laugh.

The adjective primitive

relates to the simple,

natural way humans lived

in their early

stages of development.

There are different types

of laughter, including

giggles - childlike laughter

in a quiet but uncontrolled way.

And guffaw is when you

laugh out loud, often at

something someone has said.

Mammals are animals,

including humans, which

give birth to live young

and feed them with milk.

And finally, a young animal

which is not fully grown

can be called a juvenile.

Well, it's been a laugh

a minute, Sam, but

unfortunately our six

minutes are up.

Join us again soon for

more trending topics,

useful vocabulary, and,

who knows, maybe some

terrible jokes, here at

6 Minute English.

Bye for now!

Goodbye!