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Annotated Bibliography "Animation: Normal Ear, Ear with Hearing Loss, and Cochlear Implant Procedure."Medical Devices. FDA, 23 Sept. 2011. Web. 19 Mar. 2013. This animation on the FDA’s website leads us through the workings of a normal ear, then an ear with hearing loss, and finally the cochlear implant procedure. The first diagram shows the outer, middle, and inner ear with all of the internal and external implant components in place. It then switches to an animation of what a normally functioning ear looks like. The animation moves to show a similar ear, but with less sound transmitted from the outer ear to the auditory nerve due to hearing loss. Then the animation leads us step by step through the surgery and adjustment of a cochlear implant as it is inserted. Finally, the animation shows how the working cochlear implant operates, with the microphone converting the sound wave to an electrical signal, which travels along a wire through a hole in the cochlea to stimulate the nerve to the brain. The incredible detail and images of this animation make the process so clear that our audience will likely find it enormously helpful. "Cochlear Implants." ASHA.org. American Speech-Language-Hearing Association, 2013. Web. 19 Mar. 2013. The American Speech-Language-Hearing Association’s article on cochlear implants provides an excellent and very helpful, well-organized overview of cochlear implants. The article is divided into five sections: what cochlear implants are, how they work, where one can go to get one, what is involved in the process of getting one, and who is best suited for them. The practicality of this article is enormously helpful because the information is written clearly for lay people. The article defines a cochlear implant as a “device that provides direct electrical stimulation to the auditory nerve in the inner ear.” It explains the external and internal parts of the implant, and describes the cochlear implant centers around the country where people can undergo the process. It outlines the process of testing and surgery involved in getting the implant, and finally it lists the characteristics of adult and child patients that make them suitable for the device. "Cochlear Implant Information." Johns Hopkins Medicine. The Johns Hopkins University, The Johns Hopkins Hospital, and Johns Hopkins Health System, n.d. Web. 21 Apr. 2013. John Hopkins offers information on how cochlear implant enable hearing. Sounds are coded with the speech processor the programming of which selects the important features of incoming sounds transmitted to the brain. These codes a presented through channels in the electrode array, allowing a user to perceive pitches. Power and tempo (or loudness) of the sounds are conveyed through patterns in the impulses. Cochlear implants do increase spoken communication and perception of environmental sounds. To realize the full potential of cochlear implants, early implantation is best, and must be paired with precise programming and communication training. The site also gives information about natural hearing, candidates for cochlear implants, the surgery, programming, and a specific section on implantation in young children. For cochlear implants to work well in children, they should be implemented early. Children will also need extensive rehabilitation to give meaning to sounds and support from their families and professionals around them to gain sophisticated communication skills. Rehabilitation with pathologists and deaf educators is key to success with cochlear implants. Training encourages detection and imitation skills necessary for oral language development. "Cochlear Implants." National Institute on Deafness and Other Communication Disorders. National Institute of Health, Mar. 2011. Web. 18 Mar. 2013. Cochlear implants result in successful speech perception in children. Currently, the earliest age of implantation is 24 months, but there are reasons to reassess this age limit. Implantation at a younger age may limit the negative consequences of auditory deprivation and allow more efficient acquisition of speech and language. Determining whether cochlear implant benefits are greater in children implanted at age 2-3 compared with those implanted at age 4-5 might resolve this issue, but sufficient data are unavailable. Also, it is unclear whether the benefits of implantation before age two would offset potential liabilities. A small number of children under age 2 have received implants, both internationally and in the United States. Cochlear implants principally have been performed in this population because of the risk of new bone formation associated with meningitis, which might preclude implantation at a later date. Speech and language data obtained on such children will be helpful in determining the potential benefits of early implantation and therefore may help to guide future policy. "How Does a Cochlear Implant Work?" Cochlear Implant Online. Cochlear Implant Online, 2012. Web. 19 Mar. 2013. Basically, there are three sections work together to deliver sound to the brain. In normal hearing the outer ear picks up sound and sends the sound waves down the ear canal to the eardrum. These sound waves cause the eardrum to vibrate, in turn causing the tiny hair cells inside the cochlea to move. The hair cells absorb the movement and change it into electric impulses which are sent to the hearing nerve fibers of the brain. The brain interprets these impulses as sound. Technically, cochlear implant have two parts; an internal part and the external part including the speech processor. Sounds enter the speech processor through a microphone, and the process converts them into digital signals. The digital signals travel through the coil transmitter and are then sent through the skin to the receiver part of the internal implant. The receiver changes the signal into electrical energy which is sent along an electrode array that is connected to the cochlea. The electrical impulses stimulate the auditory nerve, bypassing the damaged hair cells. As with natural hearing, the brain interprets the simulation as sound. Hyde, Merv, and Des Power. "Some Ethical Dimensions of Cochlear Implantation for Deaf Children and Their Families." Journal of Deaf Studies and Deaf Education Winter 11.1 (2006): 102-111. This article, instead of illustrating the cochlear implants itself, offers a comprehensive overview of the social controversy over the technology. Its discussion sheds light on a more appropriate application of cochlear implants to children from broader backgrounds. Implantation in young deaf children gives rise to controversy concerning ethnic issues between people that perceive deafness as curable disability and those who do not see deafness as a condition that needs to be fixed. The implantation decision not only involves many ethical considerations such as informed consent, risk-benefit determination, and children’s right, but also impacts the personal, social, communal, and cultural lives of implantees and their families. However, the access to this technology and related information is not equally available to families. Access depends on socioeconomic status and race. More studies on how these factors affect outcomes of the technology should be conducted. Meanwhile, the inequality problem should be addressed by public agencies so more individuals and families suffering from deafness can learn about their choices. "Inside a Cochlear Implant Surgery." Cochlear Implant Online. Cochlear Implant Online, 8 Apr. 2008. Web. 19 Mar. 2013. There are several myths about cochlear implant surgery, which misleads those individuals and families who considering receiving the device and prevents them from making an informed decision. The author of the article, who got an opportunity to witness a cochlear implant surgery on the spot, wrote about her experience and corrected four of the typical misunderstandings. The surgery is often perceived as a dangerous operation that makes a hole in the skull with the potential possibility to paralyze facial nerves and get meningitis afterwards. This intimidating description is not accurate at all, according to the author, since the actual surgery only involves a small incision and bleeding as well as limited chances to endure the negative aftermaths.This article helps to correct the popular bias against the cochlear implant surgery. With its objective description of and attitude towards the surgery, people are able make a more reasonable choice by weighing the risks and benefits. Kral, Andrej, and Gerard M. O'Donoghue. "Profound Deafness in Childhood." New England Journal of Medicine 363.15 (2010): 1438-450. Childhood deafness affects more than just an individual’s ability to hear sounds. Kral and O’Donoghue examine the other medical ramifications of childhood deafness in this article. Recognizing or differentiating sound is part of a child’s process in learning how to abstract and categorize stimuli. These perceptual objects are formed in the cerebral cortex, which is also responsible for conscious experience and sensory learning, and it continues developing until adulthood. Deafness, therefore, impair cortical development because it fundamentally alters the auditory system. If this system does not develop as a child, complex auditory functions and speech perception cannot be comprehensively established late in life. “The acquisition of spoken language requires auditory input and interaction with the environment.” Additionally, when teaching children who are deaf, information that is typically represented through sound is represented in other forms. This change in representation can have adverse cognitive effects, including the ability to scan and retrieve phonological and lexical information. Cochlear implants, therefore, should be considered only for children who still have auditory plasticity. Sharma, Anu, Michael F. Dorman, and Anthony J. Spahr. "A Sensitive Period for the Development of the Central Auditory System in Children with Cochlear Implants: Implications for Age of Implantation." Ear and Hearing 23.6 (2002): 532-39. Sharma, Dorman, and Spahr examine the consequences of receiving cochlear implants at different ages during childhood. A central issue when discussing pediatric cochlear implants is finding the ideal age for the implant. The common belief is that an individual will have better results at an early age rather than later in childhood because absence of sound causes degeneration of the central auditory system. The authors compared the P1 latency of naturally hearing subjects ranging from .1 to 20 years of age to those of children with cochlear implants at ages ranging from 1.3 to 17.5 years old. From these data they were able to create a range of “normal” latency. They found that those who received the cochlear implants at an early age were within this range, whereas those that receive it later in life fell outside the range. Being inside this range, however, was not an instantaneous result of the implant. “As a group, congenitally deaf children implanted under 3.5 yr of age demonstrated age appropriate P1 latencies by 6 mo postimplantation.” The time period before a child reaches approximately 3.5 years old is a period in which the auditory system is plastic enough to develop at normal levels post implant. "Single Channel versus Multi-Channel Cochlear Implants." HealthyHearing.com. Healthy Hearing, n.d. Web. 21 Apr. 2013. This website offers explanations on how multichannel cochlear implants offer more accurate information about sounds for the user. The number of channels is connected to the number contacts between the electrode array and the inner ear. Each of these simulation sites represent a pitch or frequency of sound. Incoming sounds are separate along these channels to convey a differences. Understanding and explaining multichannel demonstrates the the advances in technology. Cochlear implants were single channel devices when they were first used. Multichannel cochlear implants increase an individual’s ability to understand speech because of the differentiation in pitches and frequencies. People who have received cochlear implants more recently demonstrate better oral communication skills, particularly those involved with recognizing someone else’s speech. Svirsky, Mario A., Amy M. Robbins, Karen Iler Kirk, David B. Pisoni, and Richard T. Miyamoto. "Language Development in Profoundly Deaf Children with Cochlear Implants." Psychological Science 11.2 (2000): 153-58. Mario Svirsky et al. examine the effects of childhood deafness on the language developments. Deafness at a young age dramatically affects a child's’ ability to develop language. They learn communication skills at a rate far slower than natural-hearing children, as a result of a delay in their learning. Natural-hearing children begin learning language the moment they are born because they can hear sounds. Children who are deaf have a harder time acquiring language because there is a delay in their learning. Svirsky and his colleagues also examine the difference between children with cochlear implants and those who are deaf but did not receive the device. Those with the implant exceed the rate of language development of unimplanted children who are deaf. Their rates are much closer to natural-hearing children. Oral language is especially learned through the auditory input from the cochlear implants. Wilson, Blake S. "Engineering Designs of Cochlear Implants." Cochlear Implants: Auditory Prostheses and Electric Hearing. New York: Springer-Verlag, 2004. N. pag. Google Books. Google. Web. 19 Apr. 2013. Blake Wilson provides a very detailed, scientific explanation of cochlear implants, especially the behind-the-ear (BTE) housing. Though it was written in the early 2000s and therefore is almost a decade out of date, the technology works in basically the same manner. Cochlear implants consist of the same major components now as they did ten years ago; microphone, speech processor, transmitter, receiver, and an electrode array. A huge difference in the devices is that the speech processor is now housed with the rest of the BTE components, instead of a separate unit. These ability was just emerging in the early 2000s due to the same technology used in cell phones. Wilson also discusses the placement of the electrode array. It is important to connected it along several points of the cochlear to simulate the nerve. This chapter is helpful in understanding the science and technology development behind cochlear implants.