Professor Jenny Morton, Cambridge University
Hannah - I wanted to find out more about these sheep and how they behave, so I met up with Jenny, a Professor back in my home city of Cambridge, UK.
Jenny - Sheep in a flock have a poor reputation. They follow each other, they do daft things if one sheep get stuck in a fence, another sheep will get stuck in a fence, and they also look a bit silly. But I always liken them to teenagers. Teenagers in a group don't always behave perfectly, but you get a teenager by themselves, and they're usually really quite civilised. It’s the same with sheep. Sheep in a flock can be very silly. You get a sheep by itself working under controlled conditions. They perform very well. They're very intelligent, a little bit moody, but they understand things. They learn very quickly.
Hannah - So, the kind of experimental tests that you do...
Jenny - We’re trying to design experiments that will test cognitive function in decision making in particular. Sheep can do tasks where the rule changes and they can figure out that there is a new rule and what the new rule is and perform accordingly.
Hannah - So for example, if I go down a corridor, I know at the left hand side, there's going to be a little treat for me, a little chocolate bar. And so, I keep going down the left hand side and then suddenly, you might switch that treat to the right hand side corridor and then I’ll learn to get on to the right instead of the left. That's the kind of thing you do with your sheep?
Jenny - Yeah, that's almost exactly what we do, except we use coloured buckets. So, we’ll say, “If you go to the yellow bucket, there will be a reward. If you go to the blue bucket, there won’t be a reward.” So, the sheep learn very quickly to go to the yellow and then you can switch colours so you can suddenly present them with a new pair of colours and they have to make a new decision. First, they have to go, “Oh, that's just the colour bucket test. I’ll choose one of them and then I can learn what the new role of these new colours is.” What we now do though is we actually use computer screens. So, we don't need to have buckets and they don't have to walk in. They actually just use computer screens and choose symbols off of a computer screen.
Hannah - And this type of decision making, it’s important isn’t it in everyday human life and as we’re hearing, it can be affected in Huntington's disease?
Jenny - It’s absolutely critical. In fact, that's why I started with two choice discrimination tasks because Huntington's patients can learn to do these sort of tasks that they have trouble with these sort of reversals that you were talking about. So, they learn something, but then when the rule changes, they perseverate on the old rule. So, they'll stick to the same thing they knew and they have great difficulty with flexible thinking. That's why I chose to develop that task for the sheep.
Hannah - I've heard that you've even managed to get some of your sheep playing games of football with proper goal posts and the sheep counting the goals as well. Are they able to know who’s the victorious team?
Jenny - The sheep don't play football with each other but I did teach sheep how to kick a ball into a goal because again, I'm looking for tasks of skill and motor coordination. I also wanted something that sheep didn’t normally do. Now, sheep don't normally kick a football. If they see a football on the field, they would be afraid of it because it was weird. But I taught the sheep how to kick a football because I know that it’s a good test of balance, coordination, and skill that might be useful for testing balance coordination and skill in the HD sheep.
Hannah - Thanks to Professor Jenny Morton from Cambridge University.