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Cochlear Implant Information
Spoken language is a natural and powerful system of human communication. The Listening Center provides the medical, technical, and rehabilitative resources to enhance our patients' connection with spoken language through listening with a cochlear implant.
Cochlear implants are small, electronic devices that provide awareness and understanding of sound to those who do not enjoy the benefits of sound with hearing aids. The cochlear implant employs a strategy that is distinctly different from that of hearing aids. Instead of amplifying and reintroducing the sound signal, the implant bypasses impaired inner ear structures.
Sound energy is used to directly excite the nerve of hearing. Electrical contacts placed within the cochlea send signals to the hearing nerve. These signals form a code based in those features of speech that are critical to word understanding in normal listeners. Either through a process of learning in the early, formative years or by virtue of "hearing memory," the brain is capable of interpreting this code to enable speech understanding and appreciation of the surrounding soundscape.
When we talk about a "cochlear implant" we are actually referring to a system of technologies that process and transmit information. There are four components of the system:
- An external microphone picks up sound from the environment.
- An external speech processor (a computer) translates the energies contained in incoming sounds picked up by the microphone into a code that the brain can understand. The processor is worn either behind the ear or on a belt.
- An external transmitter is magnetically attached and worn behind the ear and under the hair. The transmitter sends coded information that is based in sound to the internal receiver/stimulator.
- An internal receiver/stimulator, about the size of a quarter, is placed under the scalp, behind the ear.
It relays sound information from the internal receiver to the inner ear via wire circuits that are threaded into the cochlea. Signals transmitted down the wire directly stimulate the nerves inside the cochlea, creating a train of impulses conveyed to the brain to produce what we know as "sound."
HOW THE COCHLEAR IMPLANT ENABLES HEARING
Even when hearing loss is severe and early in onset, the hearing nerve survives and retains responsiveness to electrical currents. This means that excitation of the hearing nerve is possible.
A cochlear implant stimulates the hearing nerve with a sophisticated code. The code developed is within a speech processor that selects the important features of incoming sounds. The code is then presented across channels placed within the cochlea and enables the implant listener to perceive different pitches.
Variations in the power and tempo of the electrical signals convey various sounds by triggering different patterns of impulses in the hearing nerve. Hearing stations within the brain receive and coordinate these impulse trains, resulting in the perception of sound and the ability to distinguish differences in pitch, power, and tempo.
An individual or a family might consider a cochlear implant to address any of a number of concerns. Whether it is a family's goal for a child born deaf to develop verbal language, a parent with progressive hearing loss who wishes to monitor the safety and speech of their hearing child, or a grandparent with advanced hearing loss who desires to hear the voices of younger generations, the motivations for restoring hearing vary widely. As a result, there are many definitions of success with a cochlear implant. However a combination of personal motivation and effective guidance are common to all stories of success.
Although a cochlear implant potentially offers a range of benefits, The Listening Center attempts to help users develop a meaningful connection to the world of sound. To achieve that goal, The Listening Center has found that dedicated training with a cochlear implant is essential.
With training, a child or an adult with a cochlear implant can learn to:
- Understand and use spoken language,
- Monitor personal speech to improve clarity and intonation, and
- Detect and understand the meaning of sounds in the environment.
Because many communication cues within everyday speech escape visual detection, cochlear implants restore a level of access to spoken language that can immeasurably improve quality of life.
More than two decades of experience has shown, however, that three basic factors need to come together in order to realize the potential benefits of a cochlear implant:
- Early intervention,
- Enhancement of the device's function with precise programming, and
- Training of the recipient in the skills of communication.
A cochlear implant will most benefit individuals who:
- have inner ear hearing loss and limited speech understanding with properly fit hearing aids,
- have lost hearing after initially developing listening skills or have had severe hearing loss for a short period; in children with early hearing loss, the likelihood of optimal benefit increases if the implant is provided at an early age, and
- possess sufficient motivation or a motivated support system (e.g., parents or family) to build on the awareness of sound and ultimately comprehend the complexities of voiced and environmental sounds.
Sound waves funneled into the ear cause the tympanic membrane (eardrum) to vibrate. These vibrations cross a tiny bridge formed by the three smallest bones in the body to the cochlea, that portion of the inner ear where the "transduction" of sound wave energy to nerve impulses occurs.
The fluid-filled cochlea detects sound waves by means of microscopic structures know as hair cells.
The hair cells respond to sound waves be triggering impulses in the hearing nerve which in turn transmits a signal to the brain. The brain interprets this signal as sound.
Most profound hearing loss in sensorineural in nature - there is damage to the sensitive and vulnerable hair cells in the cochlea. Sound waves are lost or distorted and cannot be transmitted through the hearing nerve to the brain. Cochlear implants bypass the damaged hair cells by stimulating the auditory nerve directly.
Children and adults with an advanced level of sensorineural hearing loss in both ears may benefit from a cochlear implant. A cochlear implant may be considered for someone with a hearing loss that is severe enough to limit speech understanding, even with well-fit hearing aids. The inability to hear more than one half of amplified words provides a guide that helps define candidacy.
Success with a cochlear implant begins with carefully planned evaluations. These include medical, audiological, psychological, and communication testing to help ensure that a candidate is likely to derive benefit from a cochlear implant. Both childhood and adult candidates must have experience with hearing aids. Training basic communication skills is also helpful in some cases before a cochlear implant is placed.
The assessment of candidacy will evaluate a range of factors now known to be important, if not crucial to success. A cochlear implant candidate's ability to attend to sound, to make meaningful associations with sounds, and to integrate hearing into social interactions will ultimately reinforce use of the device. Skills in problem-solving, attention, and memory can further strengthen communication abilities after a cochlear implant is placed. The emotional experience of learning to hear with a cochlear implant is significant. Thus, the psychological assessment of candidates and families often provides important insights into how best to tailor a complete plan of intervention.
Counseling informs candidates and their families of what to expect. A realistic expectation of what a cochlear implant can provide is the starting point at which successful use of a cochlear implant may begin.
To determine if you are a candidate please schedule an initial consultation visit with a cochlear implant audiologist. An appointment can be made by calling 443-997-6467 or emailing firstname.lastname@example.org.
Once a cochlear implant initial consult visit is scheduled, please review the following documents.
During candidacy evaluations the audiologist presents information on available devices, highlighting the features that can help guide the choice. As one of the largest implant centers in the United States, The Listening Center has been at the forefront of technological advances and clinical practice, providing patients with a full range of device options. The Listening Center does not accept advertising funding from any implant device company. We give our patients the options of all the specific brand of implant device. We will only suggest a specific device if, during candidacy, we identify a reason that prompts the need for that particular device.
Cochlear implant surgery is performed as outpatient surgery under general anesthesia and requires between one and two hours. Because the size of the cochlea remains unchanged during development, children receive the same implant as adults. Surgical access to the inner ear is accomplished with minimally invasive techniques and vigilant monitoring of neighboring nerves, thus allowing for a safe and effective operation and a short recovery time.return to top of page
The system is activated after a period of healing, providing recipients their first opportunity to hear through the cochlear implant. While most individuals do not understand speech through the implant at first, activation marks a time of change and opens a new life chapter.
Sounds that are heard are adjusted in a process called mapping. The audiologist uses a computer to set a volume level for each of the implant's stimulating contacts to provide the most sensitive and the most comfortable levels of stimulation.
The object of cochlear implant mapping is to optimize the perception of sound. As new cochlear implant recipients learn and gain experience hearing with their device, Listening Center audiologists then reprogram and fine tune the implant. After initial adjustment to the cochlear implant, the hearing pathway gradually becomes more sensitive and effective. As the ability to use the implant improves over time, finer adjustments are made in order to enhance the quality of the perceived sound.
Rehabilitation is as essential to success with a cochlear implant as the surgery and device programming. Our rehabilitation team consists of well-trained and highly experienced speech language pathologists and deaf educators who collaborate to facilitate the development of auditory skills, spoken language, and educational achievement.
In addition to providing cochlear implant rehabilitation, our staff communicates directly with our implant audiologists in reviewing a patient's progress and programming needs, collaborates with parents and school personnel, and provides direct classroom observation of children in the school setting. The Listening Center's rehabilitative therapists have extensive experience with auditory rehabilitation, spoken language development and maintain a high standard of continuing education specific to cochlear implantation.
Pediatric Aural Rehabilitation Therapy
The cochlear implant provides the child with the ability to detect all of the sounds of speech. Auditory training is the key that unlocks a child's ability to make sense of the sound provided by the implanted device. The training naturally encourages skills such as detection, imitation and association of meaning with the sounds of spoken language.
As part of the candidacy process, The Listening Center team gathers baseline information about speech, language and auditory skills development. This knowledge allows the rehabilitation therapist to coordinate care with implant audiologists to ensure that each child has a finely-tuned implant to maximize his or her developing skills.
Auditory rehabilitation sessions at The Listening Center establish a collaborative partnership between the family and therapist. Goals and objectives developed during these sessions provide mutual focus for nurturing development in all areas of a child's life. Ongoing support to parents establishes a path to success for the child.
Read more about the importance of pediatric rehabilitation from the American Cochlear Implant Alliance.
Parents are a child's first and most important teachers. The Listening Center empowers parents with understanding of the principles of auditory skill development, communication, speech and language development, and strategies of behavioral modification that promote attention and focus. Even in the routine of a normal day, language-rich experiences can be plentiful.
Collaboration between the home, school and The Listening Center ensures a unified effort to optimize the child's listening and communication potential.
The Listening Center partners with teachers and support personnel to provide an optimal listening environment, promote language growth, and maintain the function of the cochlear implant system.
The following support and training are available to school professionals:
- Pre-implant assessments: Speech and Language; Auditory Skills Development
- School-based, in-service instruction for teachers and staff
- Individual Family Service & Individual Education Plan Development
- Observations and recommendations for strategies to be used in the classroom and in therapy
- Videotaping and analysis of communication styles and educational needs
Adult Aural Rehabilitation Therapy
Recognizing that effective communication is a lifeline to meaningful interactions with family and friends, to a rewarding career, and to successful aging, The Listening Center offers rehabilitation services tailored to the unique needs of the adult cochlear implant user. The rehabilitation program includes counseling, auditory training, and instruction in communication management.
In addition, a comprehensive approach to individual programming needs is accomplished by close collaboration between the therapist and the implant audiologist.
Counseling begins during the candidacy process and continues after cochlear implantation. We begin by providing information to guide expectations related to use of the cochlear implant and the auditory environment. This service is available to individuals, their family members, and personnel within educational and employment settings.
Rehabilitation consultation shortly after activation of the cochlear implant provides assessment of the early level of functional communication skills. On the basis of early results, The Listening Center's staff will determine whether auditory rehabilitation will provide further opportunities.
Auditory rehabilitation emphasizes the interaction of sound and language information to teach the adult to recognize the spoken messages in everyday listening situations. For example, newly acquired skills may be applied to functional use of the telephone as guided by emerging speech recognition abilities.
Training in communication skills enhances the ability to manage interpersonal and group listening situations. By understanding the impact of the environment, the speaker, and the listener, an individual can develop successful communication strategies. Strategies for difficult listening situations are practiced and options for assistive devices are explored. With guidance, implant listeners can use the technological capabilities of the device to their fullest advantage.
Every recipient presents a unique hearing history and an individual level of skill in verbal communication. The program of training and rehabilitation after a cochlear implant should reflect the unique needs of the implant listener. Our rehabilitative approach is thus individualized and modified as progress is made.