ATV refers to All Terrain Vehicle. It is also known as three wheeler, four wheeler, quadricycle, quad and quadbike. They are used by single operators. It is designed in such a way that it can handle wider variety of terrain.
The cochlea is the sense organ that translates sound into nerve impulses to be sent to the brain. Each person has two cochlea, one for each ear. The cochlea is a fluid-filled, snail shaped cavern in the mastoid bone of your skull behind each ear. Tiny bones in the middle ear transmit sound from the eardrum across the middle ear and vibrate against the cochlea.
A cochlear implant is very different from a hearing aid. Hearing aids amplify sounds so they may be detected by damaged ears. Cochlear implants bypass damaged portions of the ear and directly stimulate the auditory nerve. Signals generated by the implant are sent by way of the auditory nerve to the brain, which recognizes the signals as sound. Hearing through a cochlear implant is different from normal hearing and takes time to learn or relearn.