The same chemical plays a role in other types of affection

Jan 14, 2009 13:56 GMT  ·  By

A new scientific study shows that petting your dog or cat can have just about the same effect on your mood as being around your infant. Scientists were able to conclude that the hormone oxytocin is released in similar quantities in both cases, triggering feelings of happiness, stress and depression relief, as well as an increased feeling of trust. The chemical also plays an important role in social memory and helps facilitate pair bonding, which is crucial for humans.

Miho Nagasawa and Takefumi Kikusui, both biologists at the Azuba University in Japan, conducted a series of tests, to see if close contact between two species can generate any amount of oxytocin. A positive answer would have sustained the urban legend that claims pet owners feel much better after playing with their animals. "Miho and I are big dog lovers and feel something changed in our bodies when gazed [upon] by our dogs," shares Kikusui.

During their experiments, approximately 55 dog owners brought their pets to the lab. Urine samples were collected before a 30 minute-long playing session, to test for oxytocin levels. After playtime was over, another urine sample was taken, and the researchers measured the difference in hormone levels for all 55 participants.

According to the results, owners who played with their dogs and looked into their eyes for more than 2.5 minutes during the session exhibited a more than 20 percent increase in oxytocin levels, as opposed to those who spent the half hour in a room with their dogs, but without making eye contact. In their cases, researchers even noticed a slight drop in hormone levels.

"Maybe during the evolutionary process, humans and dogs came to share the same social cues," including eye contact and hand/paw gestures. "This is why dogs can adapt to human society," explains Kikusui, who believes that oxytocin may have played a crucial role in the domestication of dogs from wolves, more than 15,000 years ago.