PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Audiometry, Pure-Tone”

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 163 records · Page 9Linked to original sources

Comparison of pure-tone, warble-tone and narrow-band noise thresholds of young normal-hearing children.

Pure-tone, warble-tone, and narrow-band noise thresholds were compared in terms of sensitivity and clinical test-retest reliability. Eighty normal-hearing young children, equally divided in four discrete age levels (3 1/2, 4 1/2, 5 1/2, and 6 1/2 years) were examined. Thresholds were ranked from most to least sensitive as follows: warble-tone, pure-tone, and narrow-band noise. Test-retest reliability was equivalent for all three stimuli. Clinical implications are discussed.

Acoustic Stimulation↗

Backward and forward masking in listeners with severe sensorineural hearing loss.

Using synthetic stimuli, backward and forward masking by a first-formant stimulus were measured for two tasks: (1) discrimination of a second-formant transition and (2) pure-tone detection. 16 listeners with moderate to severe sensorineural hearing impairment were studied. Many of the listeners showed backward and forward discrimination masking, sometimes extending as far as 200 ms before or after the first-formant interval. There were large individual differences in degree and temporal extent of masking. The masking contribution of sensitivity shifts, as indicated by pure-tone detection levels, appeared to be limited to a range of only 50 ms before or after the first-formant masker.

Acoustic Stimulation↗

Bone conduction speech discrimination: an indication of cochlear function in the immediate postoperative period.

We illustrate that the apparent sensorineural audiometric changes immediately following stapedectomy are not indicative of a true sensorineural type hearing loss. The cochlear changes evident by postoperative pure-tone and air conduction speech discrimination audiometric tests are not reflective of the true cochlear reserve when the procedure of bone conduction speech discrimination is used. We report 25 consecutive stapedectomy cases in which most of the one-week postoperative audiograms of stapedectomized ears revealed a mid- and high-frequency sensorineural pure-tone loss and a drop in the standard speech discrimination scores. The decrease in speech discrimination, however, was not verified when using the bone-speech discrimination test, using maximum masking in the opposite ear.

Audiometry↗

Effects of sophistication on four tests for nonorganic hearing loss.

Three groups of 15 normal-hearing subjects were asked to simulate a hearing loss in one ear. Each subject was then tested on four measurements often used in determining the presence of pseudohypacusis (a comparison of the SRT to the pure-tone average, ascending vs descending pure-tone tests, the Stenger test, and pure-tone delayed auditory feedback). Results showed that as practice and sophistication on each of the procedures increased, there tended to be more improvement in the subjects' ability to "beat" some of the tests than others.

Adult↗

Pure tone delayed auditory feedback: effect of instructions.

This study compared the effect of instructions to the subject upon key tapping performance with pure-tone delayed auditory feedback. One set of instructions stressed the importance of maintaining tapping rate whereas a second set emphasized consistency of the pattern. A third set stressed rate and pattern equality. The results lead to the recommendation that instructions stress equally both rate and pattern consistency.

Acoustic Stimulation↗

Calibration force levels for bone conduction vibrators.

Two bone conduction vibrators (Radioear B71 and B72) and a headband (Radioear P-3333) have been developed to meet specifications of both the International Electrotechnical Commission and the American National Standard Institute. Pure-tone thresholds for air conduction and bone conduction were obtained from 24 normal-hearing young adults at audiometric frequencies between 250 and 4000 Hz. Results of this study are in good agreement with the standard air conduction threshold sound pressure levels (ANSI) and with bone conduction threshold force levels reported in the literature.

Adult↗

Brain stem response audiometry at speech frequencies.

Auditory-evoked brain stem response (BSR; wave V) was studied, using tone pips at three speech frequencies (500, 1 000 and 2 000 Hz) as stimuli. The tone pips consisted of 5-ms rise-decay times without a plateau. BSR recordings were made in 10 normal subjects and in 16 subjects with impaired hearing. In the normal subjects, BSR thresholds ranged from 10 to 20 dB SL at these three frequencies. In the subjects with impaired hearing, BSR thresholds corresponded well to conventional pure-tone thresholds at each frequency in cases of low- as well as high-frequency hearing loss. In all subjects with impaired hearing, the BSR thresholds were higher by as much as 25 dB than the pure-tone thresholds. The mean differences between these two thresholds at 500, 1 000 and 2 000 Hz were 11.3 +/- 8.0, 10.9 +/- 6.2 and 10.9 +/- 7.3 dB, respectively. Thus, we conclude that the BSR is useful for objective assessment of hearing thresholds at each of these speech frequencies.

Acoustic Stimulation↗

Aided and unaided narrow band noise thresholds in listeners with sensorineural hearing impairment.

This study explored the relationship between narrow band noise thresholds obtained under aided and unaided conditions with normal listeners and with subjects demonstrating sensorineural hearing impairment. Pure-tone and narrow band noise thresholds obtained under earphone conditions were found to approximate each other within 3 dB. Mean noise thresholds obtained in sound field required less sound pressure than thresholds obtained under earphone conditions. In comparing the predicted aided noise thresholds with the observed thresholds, a 4-dB mean difference was found. The close relationship between hearing aid acoustic gain and changes in aided narrow band noise thresholds suggests the use of narrow band noise audiometry in hearing-aid selection when traditional measures cannot be used.

Adult↗

[Basis and clinical application of the "contingent negative variation" in "evoked response audiometry" (author's transl)].

After repeated stimulation with an indicative stimulus and a second imperative stimulus, a slow negative potential shife, the "Contingent Negative Variation" (CNV), can be recorded in the EEG before the second stimulus. On account of the main features of CNV two qualitative tests can be used in audiometry. "Tone-CNV" is an objective test of perception of a pure-tone. The indicative pure-tone is followed regularly by a second imperative stimulus, a flash of light or a slide. The appearance of CNV is the positive sign of perception, even if the "acoustically evoked potential" (AEP) is difficult to define. Adults and children (5 to 12 years) with normal hearing or suffering from several forms of hearing loss developed a CNV, except those patients with severe brain damage. The advantage of this method is the short testing time and accentuation of AEPs. The test can be also done under sedation. In "Objective Speech Audiometry", a proof of concept discrimination, only words of one concept are combined with a second imperative stimulus. The other group of words of the second concept remains "unreinforced". After correct discrimination all normal subjects developed a CNV before the second stimulus and after the "unreinforced" concept a "Discriminative Positive Variation" (DPV). Thus, this method can be used for clinical purposes. Loss of discrimination, perseveration phenomena and hemispheric differences were observed in aphasic patients.

Acoustic Stimulation↗

Evaluation of a clinical method for measuring comfortable loudness for speech.

The reliability of a clinical method for measuring most comfortable loudness for speech was evaluated on 100 subjects with sensorineural hearing loss. The method uses spondaic words as the test stimuli. The test-retest reliability was determined for an ascending and descending approach mode for all 100 subjects as well as for subgroups categorized on the basis of severity of hearing loss and pure-tone configuration. Results indicated that reliability was not affected by approach mode, hearing loss severity, or pure-tone configuration. Test-retest differences were not significant and test-retest correlations were high (r = 0.73 to 0.93) across all subgroup categories. Clinical reliability was demonstrated by the high percentages (85 to 92%) of subjects who had test-retest differences no greater +/-5 dB. The procedure is rapid, uses no special equipment, is easily performed, and is reliable. Thus, it is recommended as the preferred clinical procedure.

Adult↗

[Tympanometry in chronic otitis media].

We present an analysis of the otological and audiological findings in 63 patients (113 ears) in which a myringotomy for suspected serous otitis media has been performed. In 98 ears (87%) the impedance data correlated with otoscopy. Tympanograms did not give further information than otoscopy alone in 49 patients with reliable pure-tone audiometrical results, whereas tympanograms would have missed 6 out of 78 ears containing fluid and 6 out of 49 ears who improved in hearing following myringotomy and transtympanic tube therapy. We feel, however, that, in patients who are too young or too retarded to be tested audiometrically, tympanometry in combination with otoscopy could eventually be helpful in settling the indication for a myringotomy, since 3 out of 83 ears with middle ear fluid and hearing improvement following transtympanic tube therapy had pathological tympanograms in spite of normal-seeming ear drums.

Audiometry↗

Age effect in hearing - a comparative analysis of published threshold data.

Numerical data from the literature on presbyacusis, in the form of pure-tone hearing threshold levels as a function of age, are subjected to critical evaluation and analysis. A formula is derived for predicting the age effect for otologically screened groups of males and females. Further, the complete distribution of hearing levels for each audiometric frequency in the range 0.125-12 kHz and at any age can be estimated with the aid of tabulated coefficients and some simple rules. The study was undertaken in connection with the work of ISO on standardization of normative audiometric data.

Adult↗

Audiotympanometric findings in myasthenia gravis.

Myasthenia gravis can be a difficult diagnostic and therapeutic problem. Our study on six patients consisted of pure-tone audiograms, tympanometry, and acoustic reflex tests. Positive findings in the myasthenia gravis patients prior to medication included hyperacusis and increase in the intensity of sound required to elicit an acoustic reflex. Following medication, the hyperacusis lessened and the intensity of sound required to elicit the acoustic reflex decreased. During follow-up of two of the patients we encountered cholinergic (overdosage) crisis in one patient and myasthenic (underdosage) crisis in the other patient. Muscle weakness can be a common factor in both conditions. The acoustic reflex test can differentiate between the two types of crises. We believe audiotympanometric tests can aid in diagnosis and treatment of myasthenia gravis patients.

Acoustic Stimulation↗

Two experiments on subtle mid-frequency hearing loss and its influence on word discrimination in noise-exposed listeners.

The present study consisted of two experiments. Experiment I was directed toward the detection of subtle mid-frequency cochlear dysfunction and the determination of word discrimination in noise for persons with noise-induced hearing loss. The presence of significantly elevated aural-overload thresholds, consistent with the presence of cochlear pathology in regions of normal pure-tone sensitivity, confirmed previous findings obtained with this subject population by other investigators. In addition, a marked reduction in word discrimination was observed in the presence of a background of competing noise. For experiment II, normal hearers listened to consonant-nucleus-consonant monosyllables filtered to match the mean audiometric configuration of the noise-exposed subjects in experiment I. Results showed significantly better performance with these filtered words by the normally hearing subjects than that by the noise-exposed group for unfiltered materials. The results of the second experiment were interpreted as providing further support for the presence of subtle auditory dysfunction in the mid-frequencies despite normal threshold sensitivity in this same frequency region.

Acoustic Stimulation↗

Using circumaural enclosures with children.

Pure-tone thresholds were obtained from 24 children between the ages of eight and 13 years using a standard, supraaural cushion (MX-41/AR), and one of four circumaural cushions. Testing was performed in quiet and in the presence of wideband noise presented at 60 dB SPL fro three conditions: Condition 1 (test) used a TDH 39 driver mounted in the MX-41/AR cushion; Condition 2 (experimental) used the same TDH 39 driver mounted in one of the circumaural cushions under investigation; and Condition 3 (retest) which was the same as Condition 1. Statistically significant differences were found between thresholds with the MX-41/AR cushion and thresholds with one of the circumaural enclosures in quiet. In noise, thresholds with three of the circumaural enclosures were significantly lower than those with the MX-41/AR cushion. A significant test/retest difference was observed for the MX-41/AR cushion at 6000 Hz in quiet only.

Adolescent↗

Masking level difference: another tool for the evaluation of peripheral and cortical defects.

Masking level difference (MLD) due to binaural unmasking was measured for speech signals (5-word meaningful sentences) masked by broad-band noise. Tests were carried out in a group of patients with unilateral cerebral lesions of vascular origin and apparently normal pure-tone audiograms (CNS patients), in a control group (normally hearing young adults) and in 5 other groups of patients (conductive symmetrical hearing loss, conductive asymmetrical hearing loss, bilateral presbyacusis, unilateral sudden deafness, Menière's disease). Testing pattern implied three or more S/N ratios in the listening conditions, of SmNm, Sdelta tNo and SmNu (noise correlated), and the speech signal intensity was 70 dB SPL re 20 muPa for the control group, whilst for the pathological cases, speech level intensities were established by means of alternate binaural loudness balance and simultaneous balancing median-plane localization procedures to assess subjective suprathreshold sound image localization at the midline. The results obtained in the control group and in the patients are discussed. With specific reference to the CNS patients, a statistically significant tendency was evident for the binaural condition to produce more MLD when the ear leading in time was ipsilateral to the normal hemisphere. The importance of this and of sensitized speech testing methods in CNS disorders is discussed on the basis of the results obtained in the CNS patients.

Acoustic Stimulation↗

Auditory test results in 500 cases of acoustic neuroma.

Auditory test results in the first 53 causes of this series of 500 acoustic neuromas were reported in 1964. Subsequent studies involving larger numbers of patients detailed new results based on these additional cases. Five hundred cases of surgically confirmed acoustic neuromas were analyzed. Pure-tone loss configurations, speech discrimination, auditory adaptation as measured by the modified tone decay test, Bekesy audiometry, short increment sensitivity index test, and alternate binaural loudness balance test data were evaluated. The results of this investigation in general confirm previous studies, although percentage figures for positive tests differed in the large series. Acoustic reflex results were reported for those patients evaluated more recently. Slightly more than half of the cases had inconsistent audiometric results in one or more aspects. Inconsistencies to the tests were examined in detail. Consistent responses to the tests appear to be related to the size of the lesion. The full battery of audiologic tests is of importance in the differential diagnosis of acoustic neuromas.

Adolescent↗

Cochlear initiation site of the frequency-following response: a study of patients with sensorineural hearing loss.

The cochlear initiation of the frequency-following response (FFR) was assessed by comparing the FFR thresholds to the pure-tone thresholds in four groups of patients suffering from different forms of sensorineural hearing loss. The groups consisted of patients suffering from (1) pure high-frequency hearing losses; (2) high-frequency hearing losses mixed with moderate low-frequency losses; (3) flat hearing losses, and (4)low-frequency hearing losses. Across groups, the pattern of thresholds of the FFR evoked by 500-Hz tome bursts paralleled the pattern of pure-tone thresholds only for the low frequencies- not the high frequencies. In order to clarify the interpretation of this result, a high-pass masking experiment was performed on patients with low-frequency hearing losses. High-pass masking noise did not affect the FFR thresholds to 500-Hz tone burst, but it produced a phase shift of the FFR at stronger intensity levels. The data are interpreted as strongly supporting the view that the FFR at low levels is initiated primarily by activity in the apical portion of the cochlea.

Acoustic Stimulation↗