A quiet revolution

22-month-old Aliyah Huget has never clearly heard the sound of her mother’s voice. Developing technology may be about to change that

By Joseph Gallivan

The Portland Tribune, Aug 31, 2004, Updated Oct 30, 2009

Of all the amazing things they do up there on Pill Hill (tinkering with stem cells, splicing mouse DNA, popping open the hippocampus), nothing beats making a deaf person hear.

On July 13, a toddler named Aliyah Huget is up at the Hearing & Speech Institute, for just another game of “find the cow” with her infant-family specialist. Behind the one-way mirror in a consulting room full of toys, Norene Kennedy Broyles gets down on her knees and enters Aliyah’s muffled world. It’s Broyles’ job to monitor the 22-month-old’s sign language, and her incipient speech. Such as it is; Aliyah can say some vowels Ñ “aah,” “oo,” “ee” Ñ but nothing that would get her very far in a sandbox of her peers.

Aliyah’s parents have decided that they want her to talk and hear, and they’ve arranged their lives around her weekly visits to the institute. Today she’s come with her father, Brian, who hears fine. Her mother, Tracy, arrives with a knock at the door, which Aliyah may or may not have picked up on her hearing aid. Tracy was born deaf, but she speaks, lip-reads and uses some signs.

Whichever way the child eventually communicates, one of her parents will be at a disadvantage. They’ve chosen to get her a cochlear implant so she can hear more and, hopefully, learn to speak. As they play together on the carpet, only Aliyah doesn’t know that today is the last day with the therapist before she goes for her operation.

Even the newest hearing aids, like the ones Aliyah and her mother use, only amplify sounds in the hope that a damaged ear can pick them up. A cochlear implant is far more bionic. The human ear contains a bony whorl Ñ the cochlea Ñ lined with about 30,000 hairlike cells that pick up air vibrations Ñ sounds Ñ and translate them into electrical signals for the brain. If these cells have been clear-cut by some disaster or defect, a hearing aid may not help.

An implant has a rubbery strip that unfurls inside the cochlea. Stuck to it is an array of 24 electrodes. These, an external microphone and a speech processor do a crude version of the job of the hair cells: converting sounds into electrical signals that the brain can understand. (This is what saved Rush Limbaugh’s hearing in December 2001.)

“Right now Aliyah can hear sounds in the range of about 500 hertz,” Brian explains. “That’s like the sound of bouncing a tennis ball on a wooden floor.” Tracy elaborates: “When this is done she could be able to hear up to 4,000 hertz, and 25 decibels of sound.”

This should be enough to hear human speech, most of which falls into the 4,000 to 6,000 hertz range. Never mind car horns and symphonies, this is what counts if this little girl is to be socialized.

Part of audiologist Marsha Owen’s job is to know what deaf people can hear.

“Once the implant is in, she’ll be able to detect sound at fairly soft levels,” she says. “Speech has all sorts of fine-tuned differences Ñ timing, intensity, pitch, etc. Ñ that tell the brain things like the difference between an ‘Sss’ and a ‘Zzz.’ Hearing sounds is one thing, but making use of that information and attaching meaning is the next part.”

She adds that stimulating the brain electrically doesn’t create the same sound. “Some adults have told us that sometimes it sounds like a robot speaking. I’ve heard one person say, ‘Your voice sounds like Donald Duck,’ ” she says.

Aliyah’s parents are a little uneasy. They’ve gone over it dozens of times. How the surgeon will carve out a piece of their child’s skull the size of a dime behind her ear and implant the electrode array. Magnets keep this in contact with the coil on the outside. The child can disconnect it whenever she wants. A processor is worn around the waist.

Brian and Tracy live in Washington County. He’s a home inspector, she’s a systems analyst for the Internal Revenue Service. Insurance covers most of Aliyah’s implant. The hardware costs about $6,000. There are three or four main manufacturers of cochlear implants, one of them a corporation called Cochlear. They went with the Cochlear Nucleus 24.

“The nice thing about Cochlear,” Brian says, brightening after all this talk about hertz and decibels, “what sold us on it, was the support you get through the company Ñ it’s kind of like Dell computer, they send you a new product in 24 hours, you don’t have to wait” for a replacement.

Waiting for a sign

By Aug. 17, the incision behind her ear from the July 24 implant operation has healed enough that Aliyah can wear the unit. In the waiting room she plays bubbles and Slinky and peekaboo, effortlessly charming the staff. Although they’ve practiced putting on the harness that holds the processor, Brian isn’t sure what to expect at the moment when his daughter will be able to hear. Brian and Tracy look to the experts for whatever cues they can.

Their surgeon, Dr. Sean McMenomey of Oregon Health & Science University’s department of otolaryngology, has done about 500 of these implants. “He’s a real serious guy,” Brian says, adding that they had a tense four-hour wait before the surgery even began. “But when he came out after the operation, he was grinning from ear to ear.”

The Hearing & Speech Institute is a nonprofit organization, independent of OHSU. It’s been up on Marquam Hill since 1927. For surgery though, patients are sent across the campus to OHSU Hospital.

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