Upward Spread Research Articles

The use of High-Pass amplification for Broad-Frequency sensorineural hearing loss

Recent research suggests that persons with sensorineural hearing impairment should derive extra benefit from amplification that eliminates or greatly reduces low frequencies, i.e. frequencies below 1 500 or 2 000 Hz. Such amplification seems to reduce the detrimental effects of the upward spread of masking on speech intelligibility, especially when listening in noisy environments. Also, current research indicates that extended high-frequency amplification, between 4 000 and 6 500 Hz is especially beneficial for optimal speech intelligibility. 9 patients with a relatively flat, moderate to severe sensorineural hearing loss were evaluated in the clinic and for daily listening situations while wearing conventional broad-frequency hearing aids with an upper range of about 4 500 Hz. They were also evaluated under these same circumstances with a hearing aid that reduces low frequencies and extends the high frequencies to nearly 6 500 Hz. Results indicate that these patients performed better and perferred the hearing aid that extends the high and reduces the low frequencies, particularly in noisy places. As a group, they did not prefer this type of amplification in quite listening situations.

Relationship of tonal masking to speech intelligibility in noise for listeners with sensorineural hearing damage

The present investigation sought to establish empirical evidence for the audiological observation that listeners with normal pure-tone thresholds below 2000 Hz and selective high-frequency sensorineural hearing loss often experience great difficulty perceiving speech in a noise background. For patients with either noise trauma or presbyacusis, masked-speech intelligibility thresholds (S/N) were about 10 dB higher than for normal observers. In an effort to provide a psycho-acoustical explanation for the speech communication deficit, pure-tone masking patterns were measured. Relative to the normal control group, listeners with high-frequency hearing loss showed as much as 30 dB more upward spread of masking, often in frequency regions of normal pure-tone threshold. The strong positive relationship between the masked-speech intelligibility threshold and the upward spread of masking suggests that it may be possible to predict the patient's speech perception handicap in noise from audiometric measurements of masked threshold. Implications of the present work for development of close-talking-microphone hearing aids will be discussed. [Work supported by an NIH Postdoctoral Fellowship awarded to the author at the Institute for Perception Research, Eindhoven, The Netherlands.]

Short-term adaptation in single auditory nerve fibers: some poststimulatory effects.

Adaptation was produced by CF stimuli with durations ranging from 10 to 300 msec and intensities within 60 dB above a unit's threshold. The exposure caused a decrement in the response to a CF test tone applied after the termination of the adapting stimulus. In general, the poststimulatory decrement seemed to depend on the per‐stimulatory response to the adapting tone and not directly on the parameters of the adapting stimulus. For example, the decrement followed a saturating function of adapting sound intensity and was approximately proportional to the per‐stimulatory firing rate. At sufficiently high test intensities, the decrement was constant and independent of test intensity, and the saturation rate produced by the test tone was reduced. These poststimulatory results are qualitatively consistent with a model previously developed to describe some per‐stimulatory effects of short‐term adaptation [R. L. Smith and J. J. Zwislocki, Biol. Cybern. 17, 169–182 (1975)]. In both situations, a peripheral saturation appears to precede adaptation and limit the effects of high sound intensities.

Temporal processing in noise by persons with noise-induced and age-related hearing loss

A variety of tasks, using a 21FC procedure, were employed to investigate auditory temporal processing in noise by hearing-impaired and normal listeners. First, temporal integration functions were measured in wide-band noise for tonal durations ranging from 3 to 985 msec at 500, 1500, 2000, and 4000 Hz. Second, detectability in the presence of a continuous narrowband (400–800 Hz) noise masker was measured for 5- and 146-msec tonal signals at six frequencies from 500 to 4000 Hz. Finally, forward masking, backward masking, and gap masking were studied for a 5-msec 1500-Hz signal and a narrow-band (400–800) noise masker. For gap masking, the masker was continuous except for a brief silence or “gap” of 20-, 50-, or 200-msec duration during each observation interval. Several general trends emerged from the data. First, all hearing-impaired subjects showed poorer than normal temporal integration at frequencies where their audiometric loss was greater than 40 dB. Second, listeners with noise-induced hearing loss exhibited the greatest upward spread of masking in the continuous masker condition. Third, forward masking functions showed no major differences between groups of listeners. Finally, subjects with noise-induced hearing loss tended to display greater masking than normals in backward- and gap-masking conditions, whereas this was not so obvious for subjects with sloping, high-frequency hearing loss. Results are discussed in terms of contemporary models of auditory temporal processing.

Some Masking Effects Produced by Low-Frequency Vowel Formants in Persons with Sensorineural Hearing Loss

Discrimination of second-formant (F2) transitions in synthetic vowels was measured with and without the first formant (F1) present, with F1 and F2 presented monotically vs dichotically, and with the onset of F1 delayed relative to the onset of F2. Twenty-three subjects with sensorineural loss were tested. When F2 was presented alone, discrimination thresholds were the same as those of normal-hearing subjects. In most sensorineural subjects, discrimination was reduced whenever F1 was present in the stimulus. F1 produced three types of masking that reduced the ability to discriminate F2 transitions: upward spread of masking and backward masking occurred when F1 and F2 were presented to the same ear; a type of central masking occurred when F1 and F2 were presented to opposite ears.

Upward turbulent fire spread and burning of fuel surface

Two-dimensional upward flame spread and subsequent steady turbulent burning of a thermally thick vertical fuel surface is examined theoretically and experimentally. The upward spread rate for vertical PMM slabs is observed to increase exponentially with time. This result is predicted in terms of measured fuel thermophysical properties, flame heights and heat feedback to the fuel surface. The local steady burning rates established after completion of upward spread exhibit a minimum at a height of 18 cm from the bottom edge and increase continuously beyond this height, becoming 70% larger at a height of 140 cm. This increase is shown to be entirely attributable to increasing flame radiation. Individual measurements of the various energy transfer components during steady burning of the PMM slabs are obtained from radiant intensity measurements of (1) the surface alone and (2) flame plus surface. Above 76 cm flame radiation ranges from 75 to 80% of the total (radiation plus convection) heat transfer from the flames to the fuel surface. Surface heat transfer by convection decreases slightly with height.

Temporal masking effects produced by vowel formants in sensorineural subjects

Deficient discrimination of speech sounds is often found in persons having sensorineural hearing loss. Our previous studies using synthetic vowels indicate that part of the discrimination problem might be due to the upward spread of masking and temporal masking that F1 produces when it is presented at high sound levels. The purpose of this study was to examine the temporal masking of discrimination produced by F1 and to compare it to the “classical” forward and backward masking seen in detection experiments. Detection thresholds were obtained for pure tones which preceded or followed a format-shaped noise. In the discrimination tests, subjects discriminated initial transitions and final transitions in the second formant of a synthetic vowel, while the onset or offset of F1 was varied in relation to the transitions. Results: On the detection task, large (10–20 dB) threshold shifts occurred when tones preceded or followed the masker by 10 and 30 msec; at 100 msec, masking was negligible in most subjects. On the discrimination task, there was evidence of temporal masking 200 msec before the F1 onset and after the F1 offset. The data suggest that shifts in detection threshold account for only a part of the temporal masking that reduces discrimination of speech-sound information.

Speech Cue Discrimination and Sensorineural Hearing Impairment: Masking of F2 Frequency Transitions

Our general purpose is to define specific aspects of the speech-discrimination deficit often found in cases of sensorineural hearing impairment. This paper describes measurements of discrimination acuity for detecting the presence of an initial transition in F2 of a synthetic vowel-like sound, depending on certain “masking” conditions of F1. The masking conditions were: F1 absent, F1 present in the same ear as F2, F1 present in the opposite ear, and F1 delayed in onset by varying amounts. In some of the tests F1 had a transition; in others there was no F1 transition. Transitions were 100 msec in duration, followed by a steady-state of 150 msec. The data indicate that F1 in the same ear produces upward spread of masking which is considerably released when the two formants are in opposite ears. In addition, F1 transitions produce a different sort of masking which further reduces discrimination. In most subjects, F1 masks discrimination of F2 transitions even when the F2 transition is complete before the onset of F1. In subjects with sloping hearing losses, some F1 masking is present when F1 is cut back by 200 msec. There was considerable variability among subjects. These data indicate that F1 produces a type of backward masking which can reduce discrimination of frequency transitions which precede F1 voicing in vowels. Findings are related to discrimination of voiced versus voiceless initial consonants.

Discrimination Loss and Masking by Low-Frequency Vowel Formants

Most persons with sensorineural hearing loss have some impairment of speech discrimination ability. In most cases, discrimination of consonants is poorer than discrimination of vowels. This study investigates the ability of hearing-impaired Ss to discriminate one type of consonant cue—a vowel formant transition. Our purpose was to study the effect of the presence of F1 on discrimination of F2 transitions. The test stimuli were synthetic vowels whose spectra approximated those of [a]; [i]; they were 250 msec in duration. When an F2 transition was presented, it occurred over the initial 100 msec, after which F2 did not change. The Ss were 23 persons with moderate to severe sensorineural hearing loss and four normal-hearing persons. Results: Some hearing-imparied Ss showed essentially normal discrimination with F1 present. However, in most of the Ss, F1 produced large amounts of masking in both [a] and [i]. The amount of masking was greater in [i] than in [a]. In this respect, the effect is not the same as the “classical” upward spread of masking. When the normal Ss were tested at sound levels approximating those used to test the hearing-impaired Ss, they showed large amounts of masking. The high sound levels at which hearing-imparied persons must listen appear to be a factor in their discrimination loss. [Work supported partly by the U. S. Public Health Service.]

Re: “Sensorineural Hearing Loss and Upward Spread of Masking”

No AccessJournal of Speech and Hearing ResearchLetters to the Editor1 Mar 1971Re: “Sensorineural Hearing Loss and Upward Spread of Masking” Ellen S. Martin, and James M. Pickett Ellen S. Martin Gallaudet College, Washington, D.C. Google Scholar More articles by this author and James M. Pickett Gallaudet College, Washington, D.C. Google Scholar More articles by this author https://doi.org/10.1044/jshr.1401.223 SectionsAboutPDF ToolsAdd to favoritesDownload CitationTrack Citations ShareFacebookTwitterLinked In "Re: “Sensorineural Hearing Loss and Upward Spread of Masking”." Journal of Speech and Hearing Research, 14(1), pp. 223–224 Additional Resources FiguresReferencesRelatedDetailsCited byJournal of Speech, Language, and Hearing Research61:9 (2376-2385)19 Sep 2018How Do Age and Hearing Loss Impact Spectral Envelope Perception?Erol J. Ozmeral, Ann C. Eddins and David A. Eddins International Journal of Audiology13:4 (283-286)1 Jan 1984Signal-To-Noise Threshold with and without Hearing AidK. Welzl-Müller and K. Sattler Volume 14Issue 1March 1971Pages: 223-224 Get Permissions Add to your Mendeley library HistoryReceived: Nov 18, 1970 Published in issue: Mar 1, 1971 Metrics Topicsasha-topicsleader-topicsCopyright & PermissionsCopyright © 1971 American Speech-Language-Hearing AssociationPDF downloadLoading ...

Comment on "Sensorineural loss and upward spread of masking".

Comment on "Sensorineural loss and upward spread of masking".

Temporal Integration at 125 Hz

An apparent lack of temporal integration for a 125-Hz signal was interpreted as having implications for the neural coding of periodicity pitch by Campbell and Counter [J. Acoust. Soc. Amer 45, 691–693 (1969)]. Watson and Gengel [J. Acoust. Soc. Amer. 46, 989–997 (1969)] suggested, rather, that the failure to observe temporal integration at 125 Hz was due to the spread of energy at the shorter durations upward into frequency regions of greater sensitivity. Consideration of the data mentioned above and additional data gathered at 125 Hz with durations of 30, 100, and 300 msec and rise/fall times of 1 and 5 msec presented with and without a noise (160 to 360 Hz), intended to minimize the upward spread of energy, indicate that the apparent lack of integration was due to the upward spread of energy. The rise/fall time does, however, seem to play a crucial role in this upward spread of energy rather than the short durations, per se. Furthermore, for higher frequencies, rise/fall times do not seem as critical.

Sensorineural hearing loss and upward spread of masking.

Pure-tone auditory thresholds were obtained in quiet and in three levels of masking noise for one normal-hearing group and five groups of subjects with different degrees of sensorineural loss. The masker was a low-pass noise, cut off at 250 Hz. It was presented at overall levels of 77, 97, and 107 dB SPL. Pure-tone thresholds were obtained at test frequencies within and above the masking band. A measure of noise rejection slope was used to describe spread of masking. Degree of loss, configuration of loss, and level of masking noise appear to have marked influences on upward spread of masking patterns in sensorineural subjects.

Mach bands in hearing.

It is difficult to explain the extraordinary capacity of the ear in discriminating pitch without assuming the existence of laterally inhibitory neural nets fed by cochlear potentials. On such an assumption, we have sought to show edge effects in direct auditory masking analogous to Mach bands found in vision. Noise bands having theoretically infinite attenuation rates outside the passband were generated by computer from 56 sinusoids spaced randomly by frequency. Monaural pure-tone-masked audiograms were obtained for each of four subjects for each of two such noise bands (480–580 Hz and 960–1160 Hz) at sensation levels of 20, 30, 40, 50, and 60 dB. Edge effects, as measured by contours of threshold shift, were revealed for all subjects, at every loudness, and were similar for both noise bands. Sharpening was greater at the low frequency end of a band and grew nonlinearly with loudness, as did upward spread of masking. Sharpening was greater for an interrupted than for a continuous masked tone and may be maximal for relatively low interruption rates. The data are consistent with the existence of laterally inhibiting neural nets and are discussed in relation to their neural basis and to other phenomena such as the pitch of noise bands and the regions of increased sensitivity often found in abrupt hearing loss.

Upward Spread of Masking in Normal and Sensorineural Subjects

In recent years, hearing aids and auditory-training units have been introduced that attempt to present speech information in the low frequencies. The present study is an initial step in the investigation of upward-spread-of-masking effects on discrimination in the middle and high frequencies. The purpose was to study the effect of a low-frequency masker on the threshold of hearing at higher frequencies. The masker was a 250-Hz low-pass noise presented at over-all levels of 77, 97, or 107 dB SPL. Pure-tone thresholds were obtained at 200, 300, 500, 1000, and 2000 Hz. Normal-hearing subjects and 27 subjects with sensorineural losses were tested. Results: Sensorineural subjects, as a group, do not demonstrate a “typical” pattern of masking. Within groups of subjects having similar losses, marked differences in upward spread of masking are found: Some subjects show less-than-normal masking; others, the same as normal. Subjects with moderately severe losses show higher masked thresholds than do subjects with mild losses and subjects with normal hearing. Subjects with severe sensorineural losses show only slight upward spread of masking.

Low-Frequency Noise and Methods for Calculating Speech Intelligibility

Speech intelligibility was tested in a low-frequency masking noise. Various conditions of speech and noise filtering below 1200 cps were employed in order to test the relative effects of direct low-frequency masking and upward spread of masking to higher frequency regions. Tests were carried out at three noise spectrum levels which corresponded to overall unfiltered levels of 85, 105, and 115 db. The results showed significant decreases in intelligibility as the noise energy was admitted progressively between 300 and 20 cps. Further, the speech frequencies between 20 and 300 cps provided no significant contribution to intelligibility under any noise condition tested. It is, therefore, concluded that the low frequency energy in the noise produced upward spread of masking. This interpretation is reinforced by the fact that spread of masking was greater at higher noise levels and also at lower speech-to-noise ratios. Implications for calculating the effects of noise interference upon intelligibility are discussed.

The comparative results and treatment for cancer of the rectum.

The frequency of upward lymphatic spread in rectal and rectosigmoidal cancer necessitates the widest possible removal of the upward lymphatic field. Combined excision is the most radical operation; the site and extent of the lesion when first seen indicate this procedure in about 75 per cent of cases. A study of 573 operations revealed that results of anterior resection in selected patients compared favorably with those of combined excision.

Speech Intelligibility in Low-Frequency Noise

Speech intelligibility was tested in a low-frequency noise. Various conditions of speech and noise suppression below 1200 cps were employed, chosen so as to test the relative effects of direct low-frequency masking and upward spread of masking to higher frequency regions. The basic unfiltered noise spectrum was approximately parallel to the speech spectrum above 300 cps (−5 to −8 db per octave); below 300 cps the noise spectrum had a slope of −1.5 db per octave. Tests were carried out at three noise spectrum levels which corresponded to over-all levels of 85, 105, and 115 db when the noise was unfiltered. The results showed significant increases in intelligibility as the noise energy was progressively removed between 20 and 300 cps. The speech between 20 and 300 cps provided no significant contribution to intelligibility under any noise condition tested. Thus we concluded that the low-frequency energy in the noise produced upward spread of masking. The spread of masking had more effect at the higher noise levels and also at lower speech-to-noise ratios (noise held constant). Implications for calculating noise interference are discussed.

ASCENDING URINARY INFECTION

The routes by which infection may travel in reaching the ureter and kidney from the bladder are: (1) regurgitation of the contents of the bladder through the ureterovesical orifice, (2) direct extension through the wall of the ureter, (3) extension of the infection by way of the lymphatics and (4) by way of the blood stream. From the clinical standpoint, Rovsing, 1 Israel, 2 Stoeckel, 3 Albarran, 4 Warschauer 5 and others believed that a stagnating urinary column due to ureteral obstruction favored the upward spread of organisms. Rovsing 1 and Melchior 6 concluded: (1) that experimental cystitis could not be produced in animals without retention of urine or trauma to the bladder; (2) that with retention of urine experimentally produced, pyelitis as a rule did not result, and (3) that trauma to the bladder with or without retention of urine produced pyelonephritis. Zeit 7 and Peterson, 8 in 1899,

Fever during childbirth. Siegert (Zentr. f. Gyn., 1928, No. 10)

Fever during labor, depending on the upward spread of infection through the genital canal, should not, according to Siegert, be an indication for operations aimed at hastening the termination of labor: observations show that the use of such operations leads to increased morbidity in the puerperal period. In such cases, it is only necessary to resort to labor-saving operations when there is no hope of spontaneous termination of labor.