"At age  Angelica Lopez is helping to break a sound barrier for deaf children.  Born without working auditory nerves she can detect sounds for the first time  and start to mimic them  after undergoing brain surgery to implant a device that bypasses missing wiring in her inner ears.  Angelica is one of a small number of U.S. children who are testing whats called an auditory brainstem implant or ABI. The device goes beyond cochlear implants that have brought hearing to many deaf children but that dont work for tots who lack their hearing nerve. When the ABI is first turned on she isnt going to be hearing like a yearold. Shell be hearing like a newborn audiologist Laurie Eisenberg of the University of Southern California tells parents. She outlined the research Friday at a meeting of the American Association for the Advancement of Science.  The children dont magically understand and use those sounds. Its going to take a lot of work Eisenberg cautioned.  Angelica cried when her ABI first was switched on scared by the sounds. But five months later her mother says the youngster uses sign language to identify some sounds  that was a cough thats a dog barking. And shes beginning to babble like hearing babies do as therapists work to teach her oral speech.  Its just so awesome to hear her little voice said Julie Lopez of Big Spring Texas who enrolled her daughter in the study at USC where researchers say shes progressing well.  Many children born deaf benefit from cochlear implants electrodes that send impulses to the auditory nerve where theyre relayed to the brain and recognized as sound. But the small fraction born without a working hearing nerve cant make that brain connection.  The ABI attempts to fill that gap by delivering electrical stimulation directly to the neurons on the brainstem the nerve normally would have targeted. Heres how it works The person wears a microphone on the ear to detect sound and a processer changes it to electrical signals. Those are beamed to a stimulator under the skin which sends the signals snaking through a wire to electrodes surgically placed on the brainstem.  The Food and Drug Administration approved the device in  specifically for adults and teenagers whose hearing nerves had been destroyed by surgery for a rare type of tumor. It doesnt restore normal hearing but can help to varying degrees.  Then about a decade ago an Italian surgeon started trying the ABI in deaf children whose younger brains are more flexible and might better adapt to this artificial way of delivering sound.  Now spurred by some successes abroad the first U.S. studies in young children are underway at a handful of hospitals. Hearing specialists are watching the work closely.  There are children who are not being helped in any other way said Dr. Gordon Hughes of the National Institutes of Health which is funding Eisenbergs study. And cochlear implants proved theres a critical time window when the brain is very receptive to auditory stimulation and can develop speech communication in ways that are surprisingly good if the stimulation is started early enough.  The studies are small each enrolling  to  children. Ages vary the Los Angeles study will implant starting at age  while some others try earlier. Children then receive intensive therapy to learn to hear.  The studies must prove safety since the ABI requires delicate brain surgery in healthy children.  Were talking about real surgery to go into a deep area of the brain said Dr. Marc Schwartz a neurosurgeon with the House Clinic and Huntington Medical Research Institutes in Los Angeles who is part of the USC study. This is a precise operation that requires exacting technique.  In skilled hands complications appear rare said Robert Shannon a USC professor of otolaryngology who helped develop the device. Postsurgery stimulator complications can include nonauditory sensations such as tingling of the face or throat.  Next questions include who are the best candidates and what benefit to expect  if children really will develop speech as well as with cochlear implants and hear well enough to talk on a phone. Scientists know far more about how to stimulate the inner ear than the brain directly Shannon noted.  What were giving to these kids is something very different than what any normal system would be getting he explained. To untangle that scrambled pattern the brain is picking up the slack. Its covering our tracks."