Ferrets in Research
by Dr June McNicholas
Here's a summary of a 'ferrety' article submitted to New Scientist in December 2006.
I'm not sure how many of you read New Scientist but it is complusive reading for me. It aims to bring hard science to a more general readership. I wouldn't say it treats science lightly but it makes it more digestible by giving a fun approach to scientific reports. (Where else could you read about sniffer dogs trained to locate whale poo in the open ocean, or to discover the science of 'wobblology', the investigation of wonky tables, or the evolution of beer?!) And what ferret owner could resist a headline of 'Party Ferrets to the Rescue'? Especially when coupled with a marvellous cover photo of ferrets in party hats holding cocktail glasses?!
Ferrets don't usually spend a lot of time at cocktain parties (although correct me if I'm wrong) but they have inherited from their wild polecat ancestors the need to be able to locate sounds from possible prey in areas where sound is more important than sight. So ferrets were chosen by Andrew King, a neurophysiologist at Oxford University, as the ideal animals to train for his experiments into how people with hearing difficulties might be able to learn to localise sounds. As the article states 'Crowded bars and noisy parties are no fun if you have a hearing problem. Maybe ferrets can help'.
We've all experienced difficulty in conducting conversations in night clubs or noisy environments. How much harder is it for peoplewho already have a hearing problem? How do they filter out sounds they want to hear from other sounds invading the environment? Most of us, with effort, can do so in necessary, but it can be very problematic for people who have an existing hearing problem.
Andrew King and his team at Oxford University trained ferrets to respond to sounds by going to a drinker attached to a speaker if they heard specific sounds coming from a speaker. The ferrets were then surrounded by sounds coming from a ring of speakers. Ferrets who correctly identified where sounds were coming from responded by going to the drinker attached to the relevant speaker. It wasn't difficult to train the ferrets to do this. Knowing ferrets, they probably thought it was a huge game (ferrets have little conception or respect for science, even at Oxford!).
Once the ferrets were reliably visiting the drinker at the correct speaker, they were fitted with an ear plug in one ear. This made it more difficult for them to locate where the sounds were coming from - much like the problems experienced by people with partial hearing. Predictably, the ferrets were far less accurate at detecting the right speaker when they had an ear plug. However, over time, the ferrets' ability began to improve as they learned to adjust to their ear plug, until their accuracy (within about 24 days) was almost as good as before they were fitted with the ear plug.
The next stage was to remove the plug and see whether the ferrets' performance was as good as the pevious 'non-plug' performances. It was; the ferrets performed at their pre-plug accuracy. So far, so good. But what happens when you re-fit the ear-plugs after a few weeks? Would the ferrets return to having difficulties, or would they have 'remembered' how to adjust? It was found the ferrets' performances were nowhere near as poor as when they first had ear-plugs fitted. They seemed to have learned and remembered how to adjust to the problems of partial hearing.
Although it sounds quite a fun experiment, it is the first time that it has been proved that adult animals can relearn to localise sounds, giving hope that training can be given to people with partial hearing to help them improve their ability to 'tune in' to relevant sounds and screen out non-relevant ones'
Initial experiments using the same technique on human subjects show encouraging results. It seems that the human brain may be able to 'return' the ear via various changes in the messages sent to and from the brain and the ear, instructing a boosting of weak signals and a dampening down of stronger ones where this is the desired effect.
It could be good news for people with hearing problems - thanks to the ferrets! Thanks should also go to the Oxford team for selecting ferrets for their trials. Promotion of ferrets as intelligent, interactive, experiments can only be a good move. Besides, just think of all the fun the ferrets and the team had in doing the experiments! Good science can still be fun after all!
First Published May 2007