When a deaf toddler gets cochlear implants, a whole new world opens up.

At 16 months, she played the piano and "sang."

Four-year-old Mecaden Bennett likes to give a running commentary whenever she watches her mother change her little brother's diaper. She exclaims, "Ew, Mommy, Levi stinks!" or "All clean!" -- neither of which would be worth noting except that Mecaden is deaf. When she was a baby, she couldn't hear a sound unless it was as loud as a jet engine blaring in her ear.

Had she been born earlier, the Raleigh, North Carolina, preschooler would probably be delivering her diaper play-by-play in sign language, if at all. But her parents, Emily and Todd, chose to get her cochlear implants -- surgically implanted electronic devices -- so now she's learning to speak and understand just like a hearing child. Mecaden got an implant in one ear when she was a year old, and then one in her other ear 17 months later, during a critical window for her language development. "We were beyond thrilled to have the option of implants," says Emily, stressing that she and her husband never felt they were "fixing" their daughter. "We wanted Mecaden to be able to communicate with us and the rest of our family, and we felt that if we could give her the gift of hearing, why wouldn't we?"

The Bennetts' attitude reflects a major shift within the deaf culture. Ironically, while it's trendy for parents to teach sign language to their hearing babies, parents of deaf children are helping them avoid speaking with their hands. Approximately 10,000 deaf children are born in the United States every year, and more than half of those who are diagnosed as a baby now get an implant before their second birthday. Within five years, more than 90 percent of deaf children born to hearing parents will have at least one implant by the time they are 18 months old, predicts John Niparko, M.D., a cochlear-implant surgeon at Johns Hopkins Hospital, in Baltimore.

Amazing Technology

In order for a child to hear, sound must travel down the ear canal to the cochlea, the snail-shaped organ that connects the auditory nerve to the brain. The cochlea is lined with microscopic hair cells that vibrate when they're stimulated by sounds. When the hair cells vibrate, the nerve fibers at their base carry electrical signals to the brain, which interprets them as language or environmental sounds, such as a dog barking, rain hitting the roof, or a mother's voice. When a child like Mecaden has extensive sensorineural hearing loss, the hair cells don't work -- so the implants bypass them.

At the heart of each device is an electrode array that a surgeon inserts into the cochlea. A receiver is implanted under the skin on the mastoid bone, which is behind the ear, and then the electrodes and receiver are connected. A child wears other parts of the device outside her body, including a speech processor that looks like a hearing aid. It's connected to a radio coil, which resembles a small steering wheel, and is held in place by a magnet that attaches to the receiver under the skin. A microphone in the speech processor picks up sounds, converts them to an electrical code, and sends them to the coil, which delivers them to the receiver. From the receiver, they travel to the electrode array and then to the brain.

Early models in the 1970s made it possible for deaf people to hear some sounds, but because the devices had only one electrode instead of an array, it was hard for users to understand what they heard. The first implant recipients were adults who had lost their hearing after learning to speak and listen. They were ideal candidates because they already knew what things sounded like. By 1990, as more electrodes were added and the technology was fine-tuned, the FDA approved implants for children ages 2 and older. In 1998, the age was lowered to 18 months, and in 2002, it was lowered to 1 year. The popularity of cochlear implants has grown steadily since then.

Although one implant has been proven to help a child learn to speak and listen, studies show that having two makes it much easier to hear in noisy environments and to figure out where sounds are coming from. Recent research from UT Southwestern Medical Center, in Dallas, has also found that children with implants report having the same quality of life as kids with normal hearing. The surgery and follow-up therapy costs between $40,000 and $60,000 per implant and is usually covered by insurance -- although some insurers resist paying for a second implant.

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Two-year-old Mecaden with Todd, Emily, and brother Levi

Waiting to Hear

Mecaden's parents learned she might be deaf less than 24 hours after she was born, when she failed a routine newborn hearing screening. More comprehensive tests three months later confirmed that she had profound hearing loss. Emily had actually seen an implant for the first time about two years earlier, when she happened to share a room at a church retreat with Allison, a 27-year-old who'd lost her hearing at 18 months and gotten an implant as a young adult. When Mecaden was diagnosed, Emily contacted Allison, who introduced them to a family whose 4-year-old had an implant. "It was so helpful for us to see another little girl growing up with it," Emily says.

Mecaden had to wait until her first birthday to have the surgery at the University of North Carolina Hospital, in Chapel Hill. After being evaluated by a team of specialists, she was first required to try hearing aids. They amplify sound, but didn't help Mecaden, whose ears weren't producing any sounds to amplify. She and her parents then started sessions with an auditory-verbal therapist. Mecaden learned to watch the adults speak and make connections between the way a word looked on their lips and what they were doing. "We were getting her ready to hear," Emily says. Having an implant involved making a serious commitment: The Bennetts had to sign a form promising to use the implant during all of Mecaden's waking hours and to continue speech-therapy sessions.

One month after her surgery, when the incision had healed, Mecaden was ready to have her implant turned on, or "activated." At first she was baffled, and she whimpered for 15 minutes. She could hear everyone's voice, the chairs scraping, and a fan blowing, but she had no idea what to make of any of it. "She'd had only four senses before that day," says Emily. "All of a sudden she was hit with this brand-new sense."

After she calmed down, the audiologist began the process of mapping -- using a computer to program the implant to provide the proper amount of stimulation so that Mecaden could hear and understand. A week later, when Emily tucked her into bed, she knew they'd made the right decision. She removed the processor from Mecaden's ear, turning off the implant. Mecaden patted the space behind her ear and began to cry. "She understood that she could hear with it, and she wanted it on," recalls Emily. Two months later, she said her first word: "Mama."

Three months after the activation, she was saying so many words that Emily stopped writing them down. Although the Bennetts initially planned to get Mecaden only one implant, they changed their mind a year after the first surgery, when their doctor told them about studies showing the benefits for children who received two implants before age 3. "Her language skills continued to improve from the time she got her first implant to when she got the second one, and they have improved light-years since then," Emily says.

When Mecaden turned 4, she listened to her family sing "Happy Birthday."

Opting Out

While implants are fast becoming the standard treatment for deafness, some parents don't want to subject their child to surgery, especially if she's medically fragile. And there are parents, primarily ones who are deaf themselves, who see implants as a form of mutilation -- or just an attempt by the medical community to correct a nonexistent problem.

Jason and Valerie Miller, of Frederick, Maryland, had no family history of hearing loss before their otherwise healthy daughter, Faith, was born deaf five years ago. Valerie immediately bought a book about American Sign Language and began teaching herself and her family. "Faith started picking it up at 7 months, and didn't seem to have barriers to communication," she says. Doctors, friends, and relatives insisted that the only way Faith would succeed in life was with an implant. However, the couple met deaf professionals and families with deaf children, and they visited their state school for the deaf. "We found a rich community who welcomed us and our daughter," says Valerie. "Our decision not to get Faith implanted involved a lot of tears, prayers, and research. But ultimately we agreed that she was perfect the way she was born, and that she could do anything anyone else could do except hear." If Faith wants an implant later in life, her parents will be supportive. "For now, she identifies herself as Deaf," says Valerie. However, Mecaden and other children with implants who are being raised in an oral environment do not. But technically, they still are.

When Emily removes Mecaden's implants before she goes to sleep, takes a bath, or goes swimming, Mecaden can't hear. At those times, the family gestures and Mecaden reads their lips. Sometimes Emily forgets her daughter is deaf. Strangers who meet her often never know. In preschool, Mecaden has worked with a teacher to prepare her to be mainstreamed in kindergarten.

But Emily will never forget the day about a year after Mecaden received her first implant, when the Bennetts met a family at their neighborhood playground. Their toddler son was a few months younger than Mecaden. He listened as she narrated her every move, and then he repeated her descriptions: "Up, up, up," as she climbed the slide, and "Down, wheeeeee!" as she slid down. "His parents started clapping for him," Emily recalls. Two years earlier, she'd thought her daughter would never speak, let alone inspire another child to increase his vocabulary. But rather than share Mecaden's whole story with them, Emily just smiled. "They were so excited that their son had learned some new words," she says. "I kept my party to myself."

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