Deaf No More: Technology Enables Mother To Hear Once More

Molly Brown lost her hearing at the age of 24, but technology enabled this mother of three to hear her children once again. This is her story.

Micrograph of a schwannoma, a tumour seen in neurofibromatosis type II

Tumour Neurofibromatosis
EVERYDAY HEAING 
 

Since the operation, Brown has begun to comprehend speech again, to understand her husband when her back is turned, to talk on the phone with her three children, even to recognize her favorite songs by John Denver and Stevie Wonder. Biologically deaf, she can hear thanks to electronic intervention. “I have zero nerves to my brain for hearing,” she says in a chatty e-mail. “And yet hear I do. The clicking of this keyboard tells me so.” Bionic men and women—human-machine hybrids—used to be purely the stuff of science fiction. Not any-more.

Today, electronic devices such as Molly Brown’s PABI are at the heart of a fast-growing field with a wide range of practical applications. Known as neuroprosthetics, these devices activate nerves when normal biological functions can’t. They help patients unable to use their hands regain rudimentary movement. For Parkinson’s sufferers, they quell the disease’s tremors. Researchers at Cleveland’s Functional Electrical Stimulation Center at Case Western Reserve University are even working on devices meant to help spinal-cord injury patients move their hands and stand and walk.

In Brown’s case, the PABI procedure required two arrays of electrodes: 14 on the surface of her brainstem and 8 buried inside. For the doctors who performed it, Derald Brackmann and William Hitselberger, the trickiest part was shooting the electrodes into just the right spot, the cochlear nucleus, where sound is translated. “You’re dealing with an area that is just 1/8 of an inch,” says Brackmann, “so it’s extremely difficult.” Five of the eight penetrating electrodes hit their marks (the three that missed did no harm), making Brown’s operation successful. Her hearing isn’t perfect, but combined with her lip-reading ability, she’s made huge strides.

Day-to-day, Brown can adjust the volume and quality of sounds she hears via a Walkman-size box at her waist. The gadget connects to a small magnetic disc fixed to her scalp that contacts the implant. Set to Program 1, the device tunes in to the surface electrodes. Program 2 contacts the embedded ones. Program 3 combines the two. “That,” she says, “is the one I like best.”

 

Losing the Ability to Hear

Brown was just 24 when started to lose her hearing. It took two surgeries totaling 30 hours to remove the tumour. Her left auditory nerve was destroyed in the process, leaving her deaf in that ear. Because she had trouble hearing with her right ear, she wore a hearing aid. NFII was never mentioned. Brown’s ordeal was just beginning. One morning in November 1985, when Michael was three weeks old, she woke up at 5 and realized she hadn’t heard him cry all night. When she tried to tell Allen, though, she couldn’t hear herself speak. “Between putting Michael to bed and waking up to feed him, my remaining hearing had gone.”

Doctors discovered another tumour, this one on her right auditory nerve. NFII was considered, and dismissed. One bright spot: During this round of surgery, the auditory nerve was spared. Still, the last vestiges of Brown’s hearing were gone. “For someone who has grown up hearing, it is very lonely being deaf,” she says. “I could be in a room with a thousand people and still feel all by myself. It is hard to imagine. Go home and stick cotton in your ears and put a hat over your head. Then go to a party and try to interact.” Brown, by nature a funny, outgoing, charismatic woman, plunged into depression.

Image Source: Wikipedia