(ABC NEWS) -- When golden retrievers visited Boston Marathon bombing victims this week, they put their paws up on the hospital beds to make it easier for patients to pet their soft, blonde fur.
First, the patients smiled, said Tim Hetzner, president of Lutheran Church Charities, which organizes K-9 Comfort Dogs. But soon, they started talking to the "furry counselors."
"They tell the dog the story of what happened," Hetzner said. "Dogs are great listeners…. They can sense when someone is struggling."
Hetzner brought five of the organization's 60 comfort dogs to Boston: Addie, Isaiah, Luther, Maggie and Ruthie. Addie and Maggie had been working in Newtown, Conn., since Sandy Hook Elementary School re-opened, but they were off this week because the children were on spring break.
Maggie and the others are certified service dogs, but instead of being paired with individuals with disabilities, they go to churches, hospitals, schools and anywhere else they're needed, Hetzner said.
The dogs, who arrived on Tuesday, spent several hours outside the First Lutheran Church of Boston on Berkeley Street, for instance, lying down on the red brick steps so that people could sit with them for a hug or two.
"Some people hold onto the dog for five minutes or more because that's what they need," Hetzner said. "It depends on the person and what they're going through."
The golden retrievers aren't the only furry friends offering free hugs. Amber Hathaway used Reddit.com to organize a dog cuddling session on Wednesday afternoon in Boston Common, according to the Lowell Sun.
"I don't have enough money to donate much, I'm not an EMT or anything like that, and no one has taken me up on my post for available housing for displaced runners," she wrote in the Reddit post. "But I still want to help. The only things I have to offer are two stupid, friendly dogs who make me feel better when the [stuff] hits the fan."
Her pugs, along with Gimli the corgi, and Harvard Dangerfield, a Samoyed, cuddled with passersby on their lunch breaks, students between classes.
There's scientific evidence that dogs have a healing power around patients and people who've experienced traumatic events, said Dr. Emma Raizman, a pediatrician at the Cleveland Clinic Children's Hospital.
Being around dogs helps decrease patients' stress by prompting the release of oxytocin, which is the hormone that bonds mothers to babies. Studies have shown that patients who are around dogs have increased levels of dopamine -- the "happy" neurotransmitter that helps relieve depression – as well as endorphins and adrenaline.
"It's actually been shown to help more than medication in a lot of the veterans, and you don't have the side effect of medications," Raizman said, adding that dogs also help other ways, too. "For people who have been through a traumatic experience, it helps them feel cared for and gives them the sense that they're able to care for someone else. It gives them a sense of control over things."
She said hugging and talking to a dog can also help people deal with their feelings in a less complicated way than divulging them to another person.
Lynn Belkin, who coordinates the Pawprints Program at Boston Children's Hospital, said she has reached out to Hetzner's group to see if any of her eight volunteer dogs could help.
She said this week has been business as usual for Pawprints, but one of the its dogs may have visited a marathon bomb victim. Belkin's group often doesn't know why a child is in the hospital.
Belkin said she's seen children who haven't smiled in days or haven't been able to move a limb, and they're suddenly able to do it when they interact with the therapy dog. Other times, the dog makes families feel at home or offers a comfort to tired hospital staffers.
"There are so many different ways dogs and handlers impact patients, families and staff here at the hospital," she said. "A dog comes in and all of a sudden things start to happen."
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