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Vol. LXI, No. 2
January 23, 2009

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The ‘Dogtor’ Is In
STEP Forum Touts Benefits of Pets

On the front page...

Do companion animals affect human health? A recent Staff Training in Extramural Programs (STEP) forum gathered in Natcher Bldg. to explore “Understanding the Human-Animal Bond: What Has Your Pet Done for You Lately?”

Pets have been an integral part of western culture over the last 10,000 years, said the University of Pennsylvania’s Dr. James Serpell in an overview. As of 2005, almost two-thirds of U.S. households had a pet. While the largest pet population is fish, followed by cats, the highest number of pet-owning households goes to the dogs.

Serpell noted that social support systems, which protect us against cardiovascular disease, depression and other illnesses, have become increasingly fragmented over the last 40 years. Our pets cost us billions annually but they offer social support.


  Kenji greets Dr. Joan Esnayra, founder of the Psychiatric Service Dog Society.  
  Kenji greets Dr. Joan Esnayra, founder of the Psychiatric Service Dog Society.  

Research shows how pets foster a short-term reduction in heart rate and blood pressure plus feelings of calmness and relaxation. Such warm feelings, said Serpell, may be mediated by oxytocin (OT) and vasopressin (VP), which are bonding hormones in all mammalian and bird species.

“Genes that code for OT and VP emerged from the duplication of a single ancestral gene early in vertebrate evolution,” he said. The bonding mechanisms may thus work between species as well as within them.

“Pets may be even better at providing social support than other people,” Serpell noted.

Dr. Patricia McConnell of the University of Wisconsin agreed, citing a survey of female veterinary students. Half said they got more support from their dogs than from their husbands.

"Dogs are nurturing, docile and love to play,” said McConnell. They also communicate social subtleties with visual signals. The human/dog bond may be based on “shared emotional [facial] expression”—we can “read” each other.

Virginia Commonwealth University’s Dr. Sandra Barker founded the Center for Human-Animal Interaction in the School of Medicine at VCU, where therapy dogs are incorporated into a patient’s treatment plan and visit patients throughout the VCU Medical Center through the center’s “Dogs on Call” program.

Virginia Commonwealth University’s Dr. Sandra Barker
Virginia Commonwealth University’s Dr. Sandra Barker founded its School of Medicine’s Center for Human-Animal Interaction.

Center research indicates that many benefit from such contact; the effects include reduced anxiety and fear in acute care patients.

Other research shows that pets serve as a buffer to stress for their owners. The presence of fish tanks helps dementia patients gain weight, for example, and interaction with dogs is associated with less pain in post-operative children. “Community-living adults,” after playing with pooches, experience reductions in blood pressure, loneliness and anxiety.

Barker’s ongoing research includes the effect of animal-assisted interactions on physiological and psychological distress in cancer patients at the Clinical Center, a study conducted with Dr. Ann Berger and Julie Hoehl of the CC.

The Psychiatric Service Dog Society, founded by Dr. Joan Esnayra, is planning an 18-month study with Walter Reed Army Medical Center and Westat: 20 soldiers with post traumatic stress disorder will receive Walter Reed’s usual PTSD protocol. Half will receive a dog; the other half, no dog. All will be followed for 12 months.

Data collection will consist of psychometric assessments and biological measures.

Accompanying Esnayra were two psychiatric service dogs (PSDs), her Rhodesian Ridgebacks Kenji and Rainbow. PSDs are service animals, not pets. PSD tasks include, but are not limited to, reminding their humans to take medications on time, interrupting dissociative episodes and creating a psychologically “safe” personal boundary in public.

Along with his companion Donna Dell’Aglio, Mike Townsend, who lives with muscular dystrophy, described how life improved thanks to Kathy, Townsend’s “monkey helper.” Kathy was provided by Helping Hands: Monkey Helpers for the Disabled, Inc.

How does Kathy help? In all activities of daily living, such as operating light switches, telephones and the TV remote, turning the computer on and off and turning book pages.

Kathy is a Capuchin monkey, a breed known for its intelligence, curiosity, manual dexterity, affinity for humans, small size and long life-span. With Kathy’s help, said Dell’Aglio, “Now Mike is working for the first time in his life.”
The 19th-century lab in “Amor Vincit Omnia [Love Conquers All],” includes a mouser. Lithograph: A. Crespin
The 19th-century lab in “Amor Vincit Omnia [Love Conquers All],” includes a mouser. Lithograph: A. Crespin. Courtesy National Library of Medicine.

Some sample questions from the audience:

  • What about grief when a pet dies? “It can be profound,” said Barker. “Very similar to what we feel for a human death, but we don’t expect to be so blown away. Society has come a long way, but we’re not there yet in seeing it as legitimate grief.”

  • Sounds like the research is pretty dog-heavy. What about cats? “In research on the impact of pets within homes,” said Serpell, “cats are included, but they’re much less suitable at being carted around in a hospital setting.”

  • Are cats harder to study because they are solitary? “The social system in felines is fascinating,” said McConnell. “They aren’t solitary, but ‘facultatively social.’ If there are enough resour-ces, even feral cat ‘queens’ stick together.” NIHRecord Icon

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