It started with the measles

Audiologist Richard Seewald's search for answers has yielded trademarked technology, international recognition and been a major factor in Western landing the National Centre for Audiology and Canada Research Chair in Childhood Hearing.

But the seeds of that advance were sewn when Seewald and another audiologist were working at the children's hospital in Halifax. A 1973-74 rubella outbreak left more than 30 infants in need of hearing aid fitting. When contracted during pregnancy, rubella or German measles can lead to multiple problems in babies, including hearing impairment.

"We didn't have the kinds of instrumentation systems and measurement procedures available now, so we had to do all the hearing aid evaluation and fitting with very crude tools," says Seewald, Canada Research Chair and School of Communication Sciences and Disorders professor in the audiology graduate program.

"We had something for adults, but even that was not what it is today, and the thing is that adults can talk to you and you can work with them. A two- or three-month-old is not going to raise their hand with the hearing of sound."

Much like eyeglasses, hearing aid fitting depends on the individual because different pitches are affected differently by the hearing loss. The challenge in Halifax was to figure out how to match the amplification characteristics of hearing aids to the auditory characteristics of babies.

"That was the problem that I saw, for which the field did not have any real answers at the time," says Seewald.

"We had all these babies with hearing loss and in time we figured out how much, but there was no science to take us the next step in knowing how to fit amplification to the babies. That's really what got me going."

Seewald already had undergraduate and master's degrees in audiology and speech pathology plus four years of work experience, so he enrolled at the University of Connecticut in 1976 to earn a PhD. He wanted to study with Prof. Mark Ross, who had written a book chapter about hearing aid fitting in young children.

In the four years with Ross, Seewald began the pioneering development of what is now referred to as the Desired Sensation Level (DSL) Method for pediatric hearing aid fitting. Used by hearing aid manufacturers and clinicians throughout the world, DSL matches hearing instruments to the specific needs of children with hearing loss.

Seewald's research continued at Dalhousie University where he was a faculty member until 1986 when he came to Western at the urging of Dean of Applied Health Sciences Dan Ling, who wanted to develop research programs in audiology and speech-language pathology.

University administration support, including funding and fundraising, has been instrumental in Seewald's efforts to pursue his original idea and, in combination with technological developments in audiology, offer hope to hearing-impaired children.

"I feel like I've had support for my work throughout the 19 years that I've been here," he says. "It's one thing that for me is very special about Western."

Research at Western's Child Amplification Lab in the early 1990s developed a number of procedures now universally applied in pediatric audiology, including use of a small probe microphone to measure the acoustical properties of babies' ears.

With the help of Western's Industry Liaison office, Seewald and colleagues transferred the technology to industry in trademarked software. They continue to do work with the manufacturers of hearing instruments and hearing aid test systems, recently releasing Version 5 of DSL.

Interest in the research at Western "exploded" in the mid-1990s, and Ontario became the first province in Canada with a universal infant hearing-screening program. This means that every Ontario baby identified and fitted with a hearing aid is fitted according to procedures and methods developed at Western. Other jurisdictions throughout the world now are doing the same as Ontario.

Seewald and Prof. Don Jamieson, the Scientific Director of the Canadian Language and Literacy Research Network (CLLRNet) at Western, conceived the idea of a National Centre for Audiology in the early 1990s. Unfortunately, it was "a rough time for funding" so they had to wait until the Canada Foundation for Innovation emerged as "an opportunity to realize the dream."

The $3.5-million NCA addition to Elborn College - designed to bring together "a critical mass of researchers, teachers and clinicians" - opened in 2001. Seewald, Jamieson and faculty colleagues Prudence Allen and Meg Cheesman coauthored the successful proposal that attracted CFI support and matching funds from many sources, including companies already enthusiastic about the research at Western.

The NCA has seven principal investigators whose leading research relates to hearing disorders in all age groups, is linked to speech-language pathology, and generates widespread interest in the clinical and academic communities. Visitors come from all parts of the world to collaborate and use the lab facilities and equipment.

When Seewald was awarded the Canada Research Chair in Childhood Hearing in 2002, it meant $170,000 a year for his research programs for seven years and $30,000 annually for the University. The federal funding also ensures that where previous research concentrated on fitting amplification devices to children older than six months, Seewald now can give greater research attention to even younger infants.

"Infant hearing impairment has huge long-term implications for communication development, educational achievement and quality of life," he says, expressing the same thought that inspired him three decades ago.