| noise, transportation | Noise associated with transportation, particularly aircraft and automobiles. (12 Dec 1998) |
|---|---|
| optical noise | <microscopy> Image defects that become especially conspicuous when the image is enhanced. In video microscopy, includes hot spots, mottle, uneven illumination, etc. (05 Aug 1998) |
| american speech-language-hearing association | A professional society concerned with the diagnosis, prevention, treatment, and remediation of speech, language, and hearing disorders. (12 Dec 1998) |
| rehabilitation of hearing impaired | Procedures for assisting a person with a hearing disorder to maximum comprehension in communication. (12 Dec 1998) |
| resonance theory of hearing | That the basilar membrane of the cochlea acts as a resonating structure, recording low tones from its apical turns and high tones from its basal turns. Synonym: Helmholtz theory of hearing. (05 Mar 2000) |
| Weber's test for hearing | The application of a vibrating tuning fork to one of several points in the midline of the head or face, to ascertain in which ear the sound is heard best by bone conduction, that ear being the affected one if the sound-conducting apparatus (middle ear) is at fault (positive test), but probably the normal one if the neurosensory apparatus is diseased (negative test). (05 Mar 2000) |
| hearing | The sensation of sound. (12 Dec 1998) |
| hearing aid | An electronic amplifying device designed to bring sound more effectively into the ear; it consists of a microphone, amplifier, and receiver. (05 Mar 2000) |
| hearing aids | Devices which amplify sound to help persons with hearing loss. (12 Dec 1998) |
| hearing impaired persons | Persons with any degree of loss of hearing that has an impact on their activities of daily living or that requires special assistance or intervention. (12 Dec 1998) |
| hearing impairment | Hearing loss A reduction in the ability to perceive sound; may range from slight to complete deafness. See: deafness, threshold shift. (05 Mar 2000) |
| hearing level | The measure of the status of hearing as read directly on the hearing loss scale of an audiometer; described in decibels as a deviation from a standard value for zero on the audiometer. (05 Mar 2000) |
| Helmholtz theory of hearing | That the basilar membrane of the cochlea acts as a resonating structure, recording low tones from its apical turns and high tones from its basal turns. Synonym: Helmholtz theory of hearing. (05 Mar 2000) |
| normal hearing | The ability to perceive sound normally. Synonym: normal hearing. Origin: G. Akousis, hearing (05 Mar 2000) |
| organ of hearing | The content of the cochlea including the portion of the membranous labyrinth containing the spiral organ (cochlear duct) and the perilymphatic channels (scalae) which lie on either side. Synonym: labyrinthus cochlearis, organ of hearing. (05 Mar 2000) |