The research found that humans will feel happier when they are with dogs for at least 5 minutes or more. This is because the act increases a chemical called oxycontin for both humans and dogs. This effect can be seen when dogs wave their tails to let people pay more attention to them. After about two weeks of playing with dogs or other animals, kids that are between ages 8 and 9 were less stressed and more focused. Additionally, their thinking and reasoning had improved. If people directly touch animals, these benefits increase more.