Australian researchers who investigated the link between holding a saltwater croc and risky gambling behaviour have been recognised in the Ig Nobel prizes, a parody of the world's greatest scientific honour.

Key points: Australian researchers awarded Ig Nobel Prize in Economics for work on gambling risk

Australian researchers awarded Ig Nobel Prize in Economics for work on gambling risk Ig Nobels celebrate quirky science findings that inspire wonder and scientific thought

Ig Nobels celebrate quirky science findings that inspire wonder and scientific thought Other 2017 winners include research on didgeridoo as a treatment for sleep apnoea and whether our ears get bigger as we age

The Ig Nobels are awarded annually at Harvard University to scientific research that "first makes people laugh, and then makes them think."

Professor Matthew Rockloff and Nancy Greer from Central Queensland University received this year's Economics Prize for their 2010 study, which looked at how people tweaked their gambling habits before or after holding a one-metre long saltwater crocodile.

"The crocodile study was really about trying to get a sneaky way of arousing people before they gambled so they wouldn't recognise their own emotional state, that they're physiologically aroused," Professor Rockloff said.

In the research, visitors to Queensland's Koorana Saltwater Crocodile Farm were asked to gamble money on a simulated poker machine immediately after they held a saltwater crocodile.



The team wanted to look at how the emotional state of the gambler changed things like the speed of their bet, the size of their bet, and the final payout.

Stay away from these if the idea of holding a crocodile turns you on. ( ABC News: Diana Hayward )

They found problem gamblers who felt excited about holding the crocodile made larger bets and felt more "lucky," while those who felt negative about the croc handling were more cautious with their gambling.

"There's this connection now, found for the first time in this study, between emotional states and your actual gambling behaviour," Professor Rockloff said.

"Excitement, if it's interpreted in a positive way, can cause you to gamble in a more risky fashion."

And why crocodiles?

"I was casting around in Central Queensland for things that were exciting. There's not a lot exciting in Central Queensland," Professor Rockloff said.

"But my wife came up with a brilliant suggestion — she said: 'We have crocodiles in Central Queensland and those are kind of exciting.'"

There was always an inkling the study might catch the eye of the Ig Nobel decision-makers, Professor Rockloff said.

"I had this vague feeling, even when I was doing the study, I said 'Well gee — this might be a really good one for the Ig Nobels.' I certainly realised how quirky the study was," he said.

"But it also has serious science behind it, and that's often what the Ig Nobels celebrate."

Sleep apnoea and the didgeridoo

Meanwhile, Australian technology — although no Australians — featured in the Ig Nobel Peace Prize study examining the effectiveness of playing the didgeridoo as a treatment for sleep apnoea.

In this study, a group of Swiss snorers took didgeridoo lessons and maintained a daily practice of the instrument for four months.

The aim? Training the upper airways to breathe more effectively through the techniques needed to master the didgeridoo, like circular breathing.

Learning didgeridoo trains the upper airways, and can prove a viable alternative to other medical interventions ( Flickr: Leon F Cabeiro (CC-BY-2.0) )

Alex Suarez, the first patient to use this method, was the inspiration for the study and instructed other study participants on how to play.

"I had snoring and sleep apnoea diagnosed in 2000 and couldn't sleep with the continuous positive airway pressure mask (a common treatment for sleep apnoea)," Mr Suarez said.

But after spotting someone playing the didgeridoo in Switzerland — and noticing how important the throat was to the instrument — he decided to give it a go himself.

"I developed my own didgeridoo playing technique specially for snoring and sleep apnoea," he said.

"Then I was measured before and after in the sleep lab using my didgeridoo technique and was cured of sleep apnoea and snoring.

"After my personal success, the University Hospital of Zurich contacted me to ask if I would be ready to lead and instruct patients, with the same sleep apnoea and snoring issues with my didgeridoo playing technique and training structure."

And it worked.

People who received daily training were less sleepy during the day, and disturbed their partners less during sleep than snorers allocated to a second group that had no training.

The researchers think the training improves the strength of the upper airways, preventing the walls of the throat from collapsing during sleep.

"Regular didgeridoo playing is an effective treatment alternative well accepted by patients with moderate obstructive sleep apnoea syndrome," the study concluded.

Cheese and the science of disgust

Did you know that more people are disgusted by cheese than by other types of food?

That's one of the findings made by a French team that are this year's winners of the Ig Nobel Medicine Prize.

In the study, 30 French people (half of whom liked cheese, and half of whom hated it) were exposed to the odour and image of different types of cheese, as well as a range of other foods.

Does this image inspire desire or disgust? ( Flickr: Jordan Johnson (CC-BY-2.0) )

At the same time, their brains were scanned to see what parts were activated when exposed to these stimuli.

The study found that when participants experienced the cheese smells or images, those who hated cheese had parts of the reward circuitry of the brain (including the globus pallidus and substantia nigra) activated, just like those who liked it.

It suggests the same parts of your brain that create a reward response may also create a disgust response in some people — causing some French to avoid one of their country's most famous products.

If you are a cheese lover — the cheeses used in the study were blue cheese, goat's cheese, parmesan, gruyere, cheddar and tomme.

Why do old people have big ears?

It was 24 years ago that British general practitioner Dr James Heathcote set out to discover whether it was really true that our ears get bigger as we age.

More than 200 patients, the oldest of them 93, had their ears measured when they visited the doctor and his colleagues.

Your ears grow a miniscule amount each year ( Flickr: Neil Moralee (CC-BY-NC-ND-2.0) )

And Dr Heathcote indeed found that people's ears get bigger over time — at the tiny rate of 0.22 millimetres per year.

His work's seen him recognised with the Ig Nobel prize for Anatomy.

"No patients refused to participate, and all the researchers were surprised by how interested (if amused) patients were by the project," Dr Heathcote reported in the study at the time.

Other studies to win prizes at this year's Ig Nobel Prizes included:

Can a cat be both a liquid and a solid? ( Physics )

Can a cat be both a liquid and a solid? ( ) Female penis, male vagina and their correlated evolution in a cave insect ( Biology )

Female penis, male vagina and their correlated evolution in a cave insect ( ) A study on the coffee spilling phenomena in the low impulse regime ( Fluid Dynamics )

A study on the coffee spilling phenomena in the low impulse regime ( ) What's for dinner? First report of human blood in the diet of the hairy-legged vampire bat ( Nutrition )

What's for dinner? First report of human blood in the diet of the hairy-legged vampire bat ( ) Is that me or my twin? Lack of self-face recognition advantage in identical twins ( Cognition )

Is that me or my twin? Lack of self-face recognition advantage in identical twins ( ) Fetal facial expression in response to intravaginal music emission (Obstetrics)

Recipients are handed their awards by real Nobel laureates, then given just 60 seconds to explain their research before the assembled crowd.

Previous Australian Ig Nobel laureates include Professor Colin Raston from Flinders University for creating a device that can unboil an egg, researchers who looked at how holding onto your urine can affect your mental processes, and Dr Karl Kruszelnicki, who won an Ig Nobel in 2002 for his work on belly button fluff.