The spiral-shaped organ situated in the labyrinth of the inner ear that transforms sound vibrations into nerve impulses for transmission to the brain, enabling hearing.
That part of the inner ear concerned with hearing. (See EAR.)
n. the spiral organ of the *labyrinth of the ear, which is concerned with the reception and analysis of sound. As vibrations pass from the middle ear through the cochlea, different frequencies cause particular regions of the basilar membrane to vibrate: high notes cause vibration in the region nearest the middle ear; low notes cause vibration in the region nearest the tip of the spiral. The organ of Corti, which lies within a central triangular membrane-bound canal (scala media or cochlear duct), contains sensory hair cells attached to an overlying tectorial membrane (see illustration). When the basilar membrane vibrates the sensory cells become distorted and send nerve impulses to the brain via the *cochlear nerve. —cochlear adj.
A device used to treat profoundly deaf people who are not helped by hearing aids. A cochlear implant consists of tiny electrodes surgically implanted in the cochlea deep in the inner ear and a receiver that is embedded in the skull just behind and above the ear. A microphone, sound processor, and transmitter are worn externally. A cochlear implant does not restore normal hearing, but it enables patterns of sound to be detected. Combined with lip-reading, it may enable speech to be understood.... cochlear implant
A cochlear implant is an electronic device, inserted under a general anaesthetic, which stimulates the auditory system, restoring partial hearing in profound sensory deafness. Although there are many types of cochlear implant, they all consist of a microphone, a signal processor, a signal coupler (transmitter and receiver), and an array of electrodes. Most are multi-channel implants. The microphone and signal processor are worn outside the body, like a conventional hearing aid: they receive sound and convert it into an electronic signal which is transmitted through the skin to the receiver. Here the signal is transmitted to the array of electrodes which stimulates the cochlear nerve. Although cochlear implants do not provide normal hearing, most profoundly deaf patients who receive a cochlear implant are able to detect a variety of sounds, including environmental sounds and speech. The duration of hearing-loss and age at implantation are among the many factors which in?uence the results (see DEAFNESS).... cochlear implants
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