Hearing aids are the medical devices which are designed to amplify the sound for an individual. It is basically an electroacoustic device. The primary aim of a hearing aid is to make speech more detectable by rectifying an impaired hearing as detected by audiometry. There are different types of hearing aid instruments, which usually differ in their size, power and circuitry. Though hearing aids are found to be very useful in case of deaf individuals but hearing aids as such are incapable of correcting a hearing loss completely. They simply act as an aid that make sounds perception more accessible for deaf individuals. As the cell loss in the primary auditory cortex region of the brain increases the degree of hearing loss also increases. This region of the brain is concerned with the processing of sound on receiving the regular stimulations. Damage to the hair cells of the inner ear also results in hearing loss which affects an individuals ability to understand speech. It is often manifested as a decreased ability to discriminate between sounds. High-impact journals are those considered to be highly influential in their respective fields. The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. It reflects the average number of citations to recent articles published in science and social science journals in a particular year or period, and is frequently used as a proxy for the relative importance of a journal within its field. It is first devised by Eugene Garfield, the founder of the Institute for Scientific Information. The impact factor of a journal is evaluated by dividing the number of current year citations to the source items published in that journal during the previous two years.
Last date updated on July, 2014