Question: How can worms help you understand how being stressed can make people ill?

Rachel McMullan answered on 9 Nov 2015:

Hi Izzy
Worms are really simple but they also have a lot in common with us. They respond to infection in similar ways to us and their brain cells (neurons) use some of the same chemicals that are altered in our brains when we’re stressed. Hopefully this story will help explain why what we learn in worms can tell us stuff about human biology a bit better.
Imagine you’re an alien and you arrive on earth. The first thing you see is a motorbike. You want to know how the motorbike works but it’s really, really complicated and if you take it apart you might not be able to fix it. But next to the motorbike is a pedal bicycle. It looks a bit like the motorbike, both have wheels and handlebars, but it is a lot simpler. You take the wheel off the pedal bike and it doesn’t work anymore. When you put the wheel back on it works again. The wheel must be important to make the pedal bike work. If wheels are important to make the pedal bike work perhaps they are also important to make the motorbike work.
Its a bit like this with worms and humans. The worm is the pedal bike in my story and humans are the motorbike. Things we learn from doing experiments in worms might help us understand more about human responses to infection.
Hope that answers your question