Seeing what they hear, to better understand ourselves

3 min read

MEEI assistant professor examines marine, land mammals for insight on hearing

It was a long drive from St. Louis to Florida, but Darlene Ketten had finally made it. Standing in the warm surf of St. George Island, she watched with delight as tiny, colorful bean clams popped out of the sand and then quickly reburied themselves as the waves foamed around her calves.

“It was gorgeous, with incredible soft, white sand,” Ketten recalled. “In the surf were minute clams — pink, blue, orange, and gold — popping out of the sand and then disappearing. … I dipped my hand in the water and tasted it.”

The year was 1971 and Ketten, then a recent graduate of Washington University in St. Louis, had made the pilgrimage to quench her years-long curiosity about the ocean. That curiosity would not only fuel her drive across America, it would also color her subsequent career as an authority on human and animal hearing in her capacity as a specialist in imaging and analyzing cochlear implants at the Massachusetts Eye and Ear Infirmary (MEEI) and as a scientist at Woods Hole Oceanographic Institution.

Working under an unusual joint appointment between Harvard Medical School and Woods Hole, Ketten, an assistant clinical professor of otology and laryngology, examines how ear structures and changes in them affect hearing. She probes the inner ear of many species, in both healthy and ill individuals, searching for clues as to how changes brought about by both evolution and disease affect hearing.

Ketten keeps her feet in the water today by walking beaches around the world to examine stranded marine mammals for clues about how they got there. Her shoreline necropsies look for ailments that might cause an animal to beach itself, with particular attention paid to whether man-made noise pollution and hearing damage played a part.

Ketten came to Harvard in 1985 as a postdoctoral fellow in Harvard Medical School’s Eaton-Peabody Laboratory of Auditory Physiology. She became a lecturer in the Department of Organismic and Evolutionary Biology in 1987 and an instructor in Harvard Medical School’s Department of Otology and Laryngology and a research associate in the Cochlear Implant Research Laboratory at MEEI in 1988. In 1993, she was named an assistant clinical professor of otology and laryngology.

At the Massachusetts Eye and Ear Infirmary, Ketten lent her imaging expertise to the study of cochlear implants and how they interact with the human inner ear. Through imaging and computer models of the ear’s structure, Ketten examines the importance of the curvature of the implant wires and placement of the individual electrodes in speech perception.

Even when working at MEEI, Ketten kept her hand in her marine work, bringing in marine specimens for nighttime scans.

Ketten worked with the New England Aquarium to examine ailing animals, including stranded seals and turtles whose health had to be assessed before they could be released.

By the mid-1990s, interest in the impact of noise pollution and Navy sonar on marine mammals was growing, as was demand for someone with Ketten’s unique combination of skills. In 1997, she accepted a joint appointment as an associate scientist at Woods Hole and began dividing her time between the institution’s facilities in Falmouth, Mass., and MEEI in Boston.