On the Monday after the Orlando mass shooting, 12 specially-trained golden retrievers arrived in Florida City to do what they do best: provide comfort.

The dogs are part of the K-9 Comfort Dog Team, a program run by the Lutheran Church Charities that now has 130 dogs in 23 states across the country.

The dogs - all golden retrievers - deploy as part of the organisation's disaster response team. Each one was picked as a puppy because of its calm demeanour, and each one was specially trained to be gentle, comforting, and affectionate. All do this without barking, jumping, or getting distracted by events and noises around them.

In Orlando last week, the animals visited hospitals and churches, attended vigils and memorial services, and met with the staff of Pulse (the nightclub where the shooting occurred), reports The New York Times.

These same dogs were in Boston after the marathon bombing and in Sandy Hook after the elementary school shooting. When there is no national crisis, the dogs work six days a week making the rounds at schools, hospitals, and nursing homes.

How the dogs help

Numerous studies have shown that dogs are special in their ability to affect human emotions, moods, and stress.

Research even suggests that they have biological effects on us by elevating the levels of the hormone oxytocin, sometimes referred to as 'the love hormone', which plays an important role in attachment forming and bonding.

"Dogs have an incredible bond with people," Brian Hare, professor of cognitive neuroscience at Duke University and author of The Genius of Dogs, told Business Insider. "Just by making eye contact with dogs, we have an increase in oxytocin. This makes dogs incredibly valuable for people under any kind of stress, or recovering from trauma."

Dog imageLCC

Oxytocin has been shown to improve trust, the ability to interpret facial expressions, the overcoming of paranoia, and other pro-social effects, Smithsonian reports.

Studies have also shown that petting dogs can help lower people's heart rates, as well as reduce stress and anxiety. The Americans with Disabilities Act does not necessarily consider comfort dogs (or emotional support dogs) to be service dogs.

Still, psychologists, psychiatrists, and doctors have used and continue to use dogs with patients because evidence shows canines can help reduce feelings of depression, as well as symptoms of post-traumatic stress disorder in veterans and survivors of childhood abuse.

These dogs also help people open up and talk about their experiences, Tim Hetzner, president of the Lutheran Church Charities, told Business Insider.

"It is very important that people in a crisis or disaster situation talk about the situation and what they have gone through. That's part of the healing process," he explained. "Dogs are safe [so] they will talk to the dog, rather than a person, since dogs are great listeners. They are confidential, they don't keep records of rights and wrongs. They are non-judgmental. They are the perfect choice."

"People will hug the dogs, they will cry on the dogs," he continued. "And, what we have found is that sometimes, when two or three people are with a dog, they will all just lay on the ground, petting the dog together … and then they will start talking to one another too."

This article was originally published by Business Insider.

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