Service dogs may also offer support in less tangible ways. People with PTSD, who otherwise tend to isolate themselves from others, seem to open up in the company of the dogs, Koffman says. Koffman has a psychiatric service dog, Ron, who he often brings to work with him. “A lot of patients who would otherwise not want to see a therapist will come into my office just to see the animal,” he says.

This aspect of service dog assistance may be especially beneficial for sexual-sassault victims, who often have been abused by people close to them and tend to have more issues with trust and relationships. “Trauma from an explosion or natural disaster typically won't cause the same level of emotional withdrawal or fear of other people,” says Christopher P. Lucas, an associate professor of psychiatry at New York University School of Medicine.

Koffman and Ritchie believe that the dogs facilitate social interaction by increasing the amount of the hormone oxytocin in the brain. Oxytocin promotes bonding and trust and has been shown in previous experiments to be released when we come in contact with babies, dogs, and other cute creatures. This oxytocin boost may put PTSD sufferers at ease around others and make them more responsive to traditional talk therapy, the researchers hypothesize.

In contrast to the military's training-as-occupational-therapy approach, some sexual assault survivors and service dog organizations are are teaching dogs to perform physical tasks to assist their owners—like turning on lights—more in the mold of a traditional service dog. For PTSD, dogs have been trained to do things like wake people from nightmares and create a buffer against crowds. Alicia wants to teach Hera to guard her back when she is turned to face an ATM or an aisle in the grocery store, which usually causes her anxiety. She also wants to train Hera to lead her to safety if she starts dissociating—disappearing into painfully vivid memories of abuse, a PTSD symptom—in public.

Koffman has reservations about this tactic: He worries that training service dogs to perform assistive tasks could help people with PTSD avoid addressing their issues, inadvertently reinforcing distorted fears they may have about the world. More research is needed to determine what works and what doesn't, he says.

“We need to be smart about what we’re researching and make sure it's based on sound clinical sense,” Yount agrees. In an effort to tease out which aspects of working with a service dog are most helpful for PTSD, the VA has taken up a study comparing the effects of service dogs who perform physical tasks and dogs who just provide emotional support.

Although Alicia is training Hera like a traditional service dog, she seems to be benefitting from her presence in other ways as well. When Alicia talks about a difficult subject, she strokes Hera, who stops wriggling around and settles against Alicia’s side, seeming to know that she needs to be more than a playful puppy at this moment.

“I am at minimum now leaving my apartment,” Alicia says. “Anyone who has ever had a dog and had a rough week knows that having to walk your dog and get your shoes on and go outside makes a huge difference.”

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