PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Loudness Perception”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,765 records · Page 98Linked to original sources
PubMed1978

Comparison of normal and impaired hearing. I. Loudness, localization.

Impaired hearing is characterized by high thresholds and reduced loudness. Loudness, however, may quickly recover as it increases rapidly from an elevated threshold. This rapid growth, known as loudness recruitment, is a sign of cochlear impairment and is generally not seen in conductive or retrocochlear impairment. Loudness recruitment means that the hard-of-hearing person detects small changes in intensity near his elevated threshold but he probably does no better than a normal listener at the same SPLs. Recruitment is often accompanied by reduced loudness summation, which means that the loudness of a band of noise does not increase as much with increasing bandwidth as in normal hearing. This reduced summation of loudness is probably why the cochlearly impaired ear has nearly the same threshold for the acoustic reflex to pure tones as to wide-band noise, whereas the normal ear has a much lower threshold to wide-band noise. Corresponding differences between normal and impaired hearing are not found in auditory localization. Rather, the evidence suggests that persons with residual hearing learn to localize sounds reasonably well. Even the inability of many hearing impaired persons to understand a speaker in a noisy environment may result more from a failure of frequency analysis rather than of localization.

Auditory Threshold↗
PubMed1987

Auditory brainstem responses in young adults with Down syndrome.

Auditory brainstem response (ABR) wave V detection levels, latency, and amplitude were studied in a group of 15 young adults with Down syndrome for whom behavioral measures of hearing sensitivity were also obtained. Comparisons were made to a group of nonretarded control subjects matched by age and sex. Auditory brainstem response detection levels were elevated, response amplitude was reduced, and latency-intensity functions were significantly steeper for the subjects with Down syndrome than for the control group. These findings were associated with a high frequency (8000 Hz) hearing loss prevalent in the otherwise normal-hearing experimental group.

Adolescent↗
PubMedDate not supplied

Understanding continuity effects with complex stimuli.

When a low-intensity stimulus A is alternated in time with a high-intensity stimulus B of relatively short duration, stimulus A is heard as continuous. This "continuity" effect is shown to occur even when the B stimulus is a series of sharp pulses at one rate and the A stimulus is a series of pulses at another rate which must produce a very different neural temporal pattern. Simple substitution models of the continuity effect are thus shown to be inadequate. A model is presented to make various types of continuity effects more understandable.

Adult↗
PubMed1988

[Changes of the voice in the Lombard reflex].

In a noisy background the vocal intensity increases (Lombard reflex). The same effect is produced by binaural masking. We demonstrate the regulation of the vocal intensity in the beginning of phonation in eight normal subjects by Hilbert transformation via an FFT analyser. The signals were recorded under normal conditions and with binaural masking. The results are discussed.

Adult↗
PubMed1988

[Changes in the hearing and discomfort thresholds in patients with the Clark/nucleus inner ear prosthesis].

The Nucleus 22-electrode cochlear implant should be fitted individually for both pitch and loudness. Loudness is related to the charge delivered, and is usually controlled by current amplitude. In special cases the loudness may be influenced by stimulation mode and pulse width. 3 examples demonstrate optimal fitting with low current intensities, using these possibilities. In addition the threshold level and comfortable level date were analysed over a 2-year period. No significant changes were found, indicating that electrical stimulation caused no damage to the remaining auditory nerve fibres.

Adult↗
PubMedDate not supplied

[Structural changes in the auditory field in relation to age].

Using a category scale we measured the loudness of narrow band noises experienced in 3 age groups (15-23, 33-45, and 60-75 years old). The narrow band noises had center frequencies between .125 and 8 kHz with sound pressure levels of 60, 75, and 90 dB each. We found the well-known high-frequency loss. However, we also found a hypersensitivity at middle frequencies correlated with high-frequency loss. The presumable causes of this hypersensitivity and its consequences for hearing aid fitting will be discussed.

Adolescent↗
PubMed1987

[A group of adolescents and its attitude towards loud music].

The purpose of this paper is to measure attitudes towards loud music and to evaluate the influence of some variables on such attitudes. The scale of attitudes towards loud music was administered to a sample of 173 sixteen-year old subjects. The majority of the adolescents show neutral or favorable attitudes towards loud music. The sex and environmental noise variables have a non significant influence on this attitude. The majority of the sampled group attend dancing places (clubs, discotheques, etc.) once or twice a month and sometimes listen to loud music at home or at friends' home. Finally, adolescents showing favorable attitudes attend dancing places or listen to loud music more often than those showing unfavorable attitudes. This paper is a first approach to a deeper research to evaluate the possibility of modifying experimentally the attitude towards loud music by means of a message displaying both physical and psychological damage this fashion has caused.

Adolescent↗
PubMed1987

Two-state compression of spectral tilt: individual differences and psychoacoustical limitations to the benefit from compression.

A psychoacoustic rationale was developed for a hearing aid design in which compression of spectral tilt was incorporated without any instantaneous nonlinear distortion. This involved switching between a 'flat' and a 'rising' frequency response; the switching was done slowly to avoid audible transients and was controlled by feedback derived from comparison of output levels in low- and high-frequency channels, approximating voiced/unvoiced detection. The effect of this switching process was to narrow the distribution of spectral tilt values compared with the input. Asynchrony between the switching and the triggering speech structures was avoided by also delaying the signal path. Unfortunately, hearing-impaired listeners performed more poorly on the switching system than on either of the control 'flat' or 'rising' frequency-responses. An explanation is offered (on the basis of growing evidence from perceptual experiments) of the perceptual importance of temporal envelope contours within individual frequency bands. It was possible, in part, to predict individuals' results in the switching condition from age and audiometric or psychoacoustic characteristics. The results suggest a modification to the switching design, and they point to an intrinsic limit to the ability of all hearing aids of the compression type to enhance intelligibility.

Adult↗
PubMed1987

The effects of increasing consonant/vowel intensity ratio on speech loudness.

It was hypothesized that speech loudness may be primarily determined by the level of the vowel and that, as a consequence, high positive consonant/vowel intensity ratios (C/V ratios) could be tolerated by hearing-impaired listeners with possible improvement in intelligibility. The present study was concerned with the effects of high C/V ratios on the loudness of speech as a necessary first step prior to more detailed studies of loudness tolerance and intelligibility. Recordings of four CVC monosyllables were digitized and one of the consonants in each word was selected for amplification relative to a constant vowel level. For each word a set of seven tokens was prepared representing a range of C/V ratios from approximately -20 dB to 9 dB. The loudness of each token was obtained through a loudness matching task involving a standard word presented at 90 dB SPL. In addition, sets of nonspeech stimuli were created to approximate the C/V ratios represented in two of the monosyllables. Loudness of nonspeech tokens was obtained using the same loudness matching paradigm. It was found that high C/V ratios had no appreciable effect on speech loudness. (The nonspeech stimuli gave similar results, however, so it was not possible to conclude that speech was unique in that respect.) The findings in general are encouraging for the further study of the influence of C/V ratio on intelligibility and the eventual incorporation of C/V processing into digital hearing aids.

Adult↗
PubMed1986

Factors affecting descending binaural loudness balances as a manifestation of adaptation.

Three trained adults with normal hearing were exposed to a continuous 1-kc/s pure tone in both ears simultaneously at 100 db SPL. In the R ear the tone was attenuated at 1 db/sec until it was inaudible. In the L ear the tone was attenuated at 5 db/sec, and S was asked to adjust the loudness in the L ear by pushing and releasing a hand-switch as in Bekesy audiometry in order to maintain so far as possible a binaural loudness match. At every reduction of 10 db in the R ear (i.e., every 10 sec) the SPL to the L ear was measured from the Bekesy-type tracing which yielded binaural loudness match. While there were inter-subject variations, for all Ss the level of the tone in the L ear (5 db/sec) had to be increased above physical equality for equal loudness, indicating the presence of more rapid adaptation in that ear. The disparity in 2 Ss progressed regularly from near zero after 10 sec to 16-17 db after 1 min. For 1 S, a constant disparity of about 6 db existed throughout the session. Binaural loudness balances by this descending method may be considered a manifestation of normal adaptation, confirming a previous report (Harbert and Young, J. Acoust. Soc. Am., 1968, 43, 752-756) for threshold differences produced by various attenuation rates at various suprathreshold starting levels. An analogous ascending procedure with 1 S yielded results susceptible to the same interpretation.

Acoustic Stimulation↗
PubMed1987

[The Würzburg auditory field, a test for prosthetic audiometry].

In the past audiology was used solely to provide data of hearing acuity only for diagnostic reasons. Even today hearing aids are selected and fitted based on various diagnostic test procedures. Our test called "Das Würzburger Hörfeld" yields primarily prosthetic data. That test is based on the principle of absolute category scaling of loudness and defines an acoustic sensation using the parameters of frequency and intensity. The test subject ranks a norrow band noise, 1/3 octave, presented at various intensities into one of the five categories: Very soft, soft, middle loud, loud and very loud. Results are presented for subjects with and without hearing aids. The difference of both scaling experiments is the functional gain of the aid.

Audiometry↗
PubMed1987

[Autoradiography study of the uptake of 3H-2-deoxyglucose in the inner ear in normal and unilaterally sympathectomized albino rats].

Using the autoradiographic technique for water-soluble substances, the uptake of 3H-2-deoxyglucose (2-DG) was measured in the inner ear tissue. The experiments were performed on 26 albino rats (22-27 days). 10 microCi/g b.w. of 2-DG were applied i.v. and the control group was immediately kept in the Camera silens in darkness. The main group was exposed to pink noise (50 Hz - 10 kHz of 60-110 dB). 8 unilaterally sympathectomised animals were exposed to pink noise of different intensity after 24h. The highest uptake of 2-DG independent of the intensity of noise was observed in the cochlear lateral wall (stria vasc., sp. lig., sp. prominentia) in the basal turn and decreased to the apical turn. The uptake in the lateral wall increased from 30-40 dB to 60dB and decreased from 60 to 80 dB exposure. The region of the inner hair cells was clearly marked by 80 dB. With increasing intensity of noise exposure, 2-DG uptake in the spiral ganglion increased continually. Unilateral sympathectomy did not result in any significant difference in the uptake of 2-DG. Therefore, the hypothesis that the decrease of 2-DG uptake in the lateral wall may be due to sympathico-adrenergic vasoconstriction is not verified by our results.

Acoustic Stimulation↗
PubMed1986

[The promontory test and electrocochleography in deafness caused by mumps].

Contradictory histological findings in patients with deafness following mumps led us to conduct electrophysiological investigations. Promontory testing (PT) and measurement of cochlear microphonics (CM) enabled us to distinguish between neural and sensory deafness. On the basis of a careful history and serological tests in 19 cases of unilateral deafness we found that the hearing loss was probably caused by mumps. In all patients except one auditory sensations could be obtained by electric stimulation of the acoustic nerve whereas no CM were detectable even with strong stimuli of 100 dB tonepips. In view of the electrophysiological findings, doubt is cast on the neural genesis of deafness following mumps as assumed by Lehnhardt (1962).

Audiometry, Evoked Response↗
PubMed1986

Growth of pulsation threshold of a suppressed tone as a function of its level.

The pulsation threshold (PT) was measured at the frequency of a probe tone in a two-tone stimulus. A suppressor tone was higher in frequency than the probe tone and was fixed in level. As the level of the probe tone was increased, three regions of performance were observed: (1) for probe tone levels below simultaneous masked threshold (SMT), PT was the same as that measured for the suppressor alone, (2) for levels above SMT, PT increased linearly with level, indicating a constant amount of suppression in dB, and (3) for higher levels a recruitment-like phenomenon was observed, in which the PT increased faster than the probe level. The maximum amount of suppression observed was equal to the difference between the PT and SMT for the suppressor alone. One interpretation is that the suppressor reduces excitation on the slopes of its own excitation pattern by the same amount that it reduces the additional excitation from a probe tone. These results are consistent with physiological data, where the amount of suppression is determined by the suppressor and is independent of the level of the probe tone.

Acoustic Stimulation↗