A study from researchers in Japan have revealed that dogs and humans share a similar hormonal response when they look at each other – the same response we feel when we look at human infants. Read below the article in which these studies were tested.
Takefumi Kikusui, an animal behaviorist at Azabu University studies oxytocin, the “love hormone” that plays a role in maternal bonding. Previous research showed that when mothers and their babies gaze at each other, it creates a “positive feedback loop” in which the mother releases oxytocin, causing the infant to stare back and release oxytocin, and so on. Kikusui decided to test whether this same effect might happen in dogs, since humans and dogs often interact while looking into each other’s eyes.
His team brought in 30 subjects and their pets, collected urine from them, then asked each human-dog pair to go into a room and interact for 30 minutes. After that, the team collected second urine samples, and compared the two.
For pairs that spent the most time looking at each other, dogs experienced a 130 percent rise in oxytocin levels, while their owners experienced a 300 percent increase. Pairs who spent little time gazing at each other showed no oxytocin increase.
In a follow-up experiment, the dogs were given a dose of oxytocin nasal spray before interacting with their owners. Female dogs under the effects of the spray spent 150 percent more time gazing into the eyes of their owners, and the owners had a 300 percent spike in oxytocin levels. Male dogs and dogs given a saline spray saw no effects.
The finding suggest that the same feedback loop seen in humans and infants is present in humans and dogs, according to the study, published in Science. Kikusui said the nasal spray affected only female dogs because oxytocin plays an important role in the female reproductive system.
The finding may explain why we feel so close with our dogs, but it also may provide an evolutionary answer to how dogs became domesticated in the first place.
Wolves, dogs’ closest relatives, interpret eye contact as a sign of hostility. Kikusui speculates that as wolves evolved, those that developed a positive oxytocin feedback loop naturally became easier to domesticate, and became dogs.
“It’s an incredible finding that suggests that dogs have hijacked the human bonding system,” Brian Hare, an expert on canine cognition at Duke University told Science.
“I’m perfectly happy saying that we can love dogs, and they can love us back, and oxytocin is probably a piece of how that happens,” Evan MacClean, another Duke researcher, told National Public Radio. “It’s really cool that there’s actually some science to back this up now.”