Many scientists devoted to studying a particular disease or condition attribute their zeal to a life-changing moment. For physiologist Richard Nichols, that moment occurred during the Vietnam War, when he visited a VA hospital near Boston.

“In the spinal cord unit there,” Nichols recalled, “was a patient who was paralyzed from the neck down from an injury he’d received during the first World War. He was treated well, but he’d been in bed for all these years.

“In the next bed was a young man in his early 20s who had also sustained a spinal cord injury. He had just come back from Vietnam. His doctor said, ‘The young guy is going to be just like the old guy in 30 years. We can make them comfortable, but that’s it.’

“I decided that was unacceptable,” Nichols said.

As a basic scientist, Nichols studies the manner in which the spinal cord regulates posture and balance. While the brain controls many motor functions, the spinal cord itself has some intrinsic motor capacities. Patterns of locomotion, for instance, are generated partly by spinal cord circuits that receive sensory information from the muscles. Associated circuits help keep the body upright and balanced using the same sensory information. The circuits can be disrupted by diseases like cerebral palsy or injuries to the spinal cord or its peripheral nerves.

However, in some spinal cord injuries, such as a broken neck, the circuits located at lower levels remain largely intact. Because the circuits can deteriorate through long disuse, the limbs of paralyzed individuals hoping to regain mobility must be exercised regularly to maintain the feedback loop. But these circuits also may hold the key to restoring balance and upright posture in addition to movement.

“When you think about it, it’s not sufficient to make your muscles go in a cyclic fashion,” Nichols said. “You have to be able to stand up out of a chair and keep your balance as you go along. That is an enormous feat.”

To learn more about how those circuits work, Nichols studies cats. That research has made him a primary target of animal rights activists, who say he conducts torturous studies that have not produced any cures.

However, Nichols has accumulated substantial evidence that the spinal cord and the musculoskeletal system are responsible for maintaining posture—evidence that will provide the basis for designing rehabilitation strategies for patients with spinal cord injury.

What Nichols does is this: He operates on a cat, severing a nerve going to a single muscle, then immediately reattaches it in the same operation. As the cat heals, the muscle regains its full strength, but the sensory information the muscles send to the spinal cord is permanently disrupted, resulting in some loss of dexterity. The barely noticeable impairment can be measured using state-of-the-art methods when the cat performs certain exercises, such as walking up and down ramps and jumping onto platforms.

Sometimes, Nichols needs to make more specific, invasive physiological measurements. To do this, he deeply anesthetizes the cat, then exposes the muscles he needs to examine. At the end of the procedure, the animal is euthanized with an overdose of anesthesia. The cat feels nothing during the entire process.

“I don’t like killing animals,” Nichols said. “I dislike it very much.”

But he uses cats because a great deal of information about feline spinal cord and motor coordination functions compiled by scientists over the past century enables researchers today to make major findings using relatively few animals. In addition, cats will be the first to benefit from any breakthroughs derived from this research.

Using cats also allows Nichols to control confounding factors that might muddy his results; this would be impossible in a study of human subjects with varying types and degrees of spinal injury.

“We’re still at the stage where we must depend primarily on animal experimentation,” Nichols said, emphasizing that the cats living in his colony are thriving and healthy, with only minor impairment.

Certainly this seems the case during a recent visit to the facility where the colony is housed. As veterinarian Mike Huerkamp eased open the door to the large room where several of Nichols’ cats roam freely, the cats froze in the classic attitude any cat owner would recognize. Two cats were on the counter, pretending to ignore the faucet gushing water into the sink.

“Who turned this on?” Huerkamp scolded as the pair casually jumped to the floor to indicate their total innocence. All the cats jockeyed for position around his legs, gracefully swishing back and forth in figure eights. The pushier ones stood on their hind legs and pawed at him.

“I find it ironic that Richard, of all people, has been targeted by the animal-rights activists because he’s such a caring person,” Huerkamp said, explaining that Nichols worked to ensure social housing for his cats.

To Nichols, the most disturbing aspect of the attacks is that they have entered his personal life. In 2000, an animal rights group ran ads in The Emory Wheel and Creative Loafing attacking his research. On two subsequent occasions, the group distributed leaflets in Nichols’ neighborhood near Emory.

In addition, last year Nichols received a threatening e-mail from an animal-rights activist who has been arrested at demonstrations around the country, including a violent 1997 protest at Yerkes. The e-mail mentioned Nichols’ wife, whose name also has been listed on a local animal-rights website.

“They came into my neighborhood, invaded my privacy and involved my family,” Nichols said. He promptly launched his own door-to-door campaign to educate his neighbors about his work and correct any misconceptions. With painstaking earnestness, he has explained how he conducts his work, what he already has accomplished and what he hopes to learn.

“Even people in my neighborhood who are extreme animal lovers and feel uncomfortable with animal research—after hearing about my research, they endorse what I do,” Nichols said.

And he offers this as evidence that the public as a whole will endorse animal research, once people learn how and why researchers do what they do.

—This article first appeared in Momentum and is reprinted with permission.