the team became interested in egg laying by worms because egg laying is one of the main behaviours controlled by serotonin a brain chemical that makes you feel relaxed and happy. this of course in interesting for doctors because of how it affects mood in humens, say dr. nakarin. the worms lay eggs about ten times an hour, and while computer vision is good at recording movement, it is more dificult to register the worms laying eggs by their side.