WASHINGTON - The moment Grayson Clamp hears his father's voice for the first time is magical -- the look on the 3-year-old's face is priceless.
The Daily Mail reports that the little boy, who was adopted by the Clamps as a newborn, received an auditory brainstem implant.
The couple opted for the experimental method after a cochlear implant failed to fix Grayson's hearing, the Mail reports.
Grayson was born without cochlear nerves, which allow humans to process sounds.
The Mail reports that adults in the U.S. have received auditory brainstem implants since 1979, but it had never been done on children. The FDA approved a clinical trial for children earlier this year.
According to the House Research Institute, the implant "was developed at the (institute) and is the world's first successful prosthetic hearing device to stimulate neurons directly at the human brainstem, bypassing the inner ear and hearing nerve entirely."
Grayson is the first boy in the U.S. to receive the auditory brainstem implant, the Mail says.
Watch the video below to see Grayson hear his father for the first time, and for more on the story:
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