Third-order synthetic sentences were aligned to make them suitable for dichotic presentation. These dichotic sentence materials were then administered to 14 normal listeners and 48 hearing-impaired subjects to determine the influence of peripheral hearing loss on test performance. Results suggest that the Dichotic Sentence Identification test is resistant to the influence of peripheral hearing loss until the pure-tone average of 500, 1000, and 2000 Hz exceeds approximately 50 dB. Beyond this level, degree of peripheral hearing loss limits its value for detecting central auditory disorder. Data are also provided on six persons with either confirmed or suspected lesions involving retrocochlear structures.

Acoustics↗

PubMedDate not supplied

New developments in evaluating central auditory mechanisms.

Five tests are reviewed for their ability to assist in the evaluation of the central auditory mechanism. These are: 1) the Masking Level Difference (MLD); 2) ipsilaterally and contralaterally evoked stapedius muscle reflex; 3) electrocochleography; 4) early brain stem responses; and 5) dichotic listening. A summary chart outlining the tests most commonly in use and their areas of special productivity is also presented.

Adolescent↗

PubMedDate not supplied

Influence of otitis media on hearing and development.

Otitis media affects nearly every child at some time; many children have mild-to-moderate hearing losses for prolonged periods. The effects of these losses on language and educational development may be significant; possible mechanisms are discussed. Especially in suboptimal listening situations, speech perception may be impaired by even a mild hearing loss. Patterns of imperception are predicted by comparison of composite audiometric data from children with middle ear effusions with speech power data, and by analysis of sound pressure waveforms of speech filtered to simulate the typical hearing loss of these patients. A new method of analysis of brain stem evoked responses, yielding response components attributable to binaural interaction, is reported. This and other evoked response techniques may be able to identify objective changes in auditory nervous system function attributable to relative sensory deprivation during development. Finally, directions for further research in this area are discussed.

Audiometry, Evoked Response↗

PubMedDate not supplied

Superior ultra-audiometric hearing: a new type of hearing loss which correlates highly with unusually good speech in the "profoundly deaf".

This paper reports 42 severely-to-profoundly deaf subjects, 6 of whom have better hearing in the range of 8 to 14 kHz than below 8 kHz. Data on speech capabilities in these six subjects suggest that this ultra-audiometric range may contribute to their speech comprehension and control.

Adult↗

PubMedDate not supplied

Human acoustic nerve action potential recordings from the tympanic membrane without anesthesia.

Explore the source record for details and available documents.

Action Potentials↗

PubMedDate not supplied

Tone burst electrocochleography in humans.

Using tone burst stimuli with fixed parameters of rise time and duration, a functional relationship has been demonstrated between frequency and intensity of the stimulus and peak latency of electrocochleographic recordings. The feasibility of a "map" of the human cochlear partition has been shown for frequencies above 2 kHz.

Action Potentials↗