Journal of the American Auditory Society最新文献

Twenty-four sensorineural hearing-impaired adults were evaluated using four directional microphone hearing aids differing only in front-to-back ratios. The speech material utilized was the Synthetic Sentence Identification Message Competition Ratios of 0, -10, and -20 dB. The primary signal was presented from a 0 degree azimuth with the competing message was presented from a direct overhead location. The results revealed a systematic improvement in speech understanding as the size of the front-to-back ratio increased. This relationship was not significantly affected by the difficulty of the listening situation.

Normal adults, hearing-impaired preschool children, and normal-hearing mentally retarded children were assessed across repeated measures for auditory thresholds at 250 and 1000 Hz. Each subject's total performance across repeated measures was plotted by group by frequency relative to the last point of 100% correct response and interpolated thresholds. The results indicate that the steepness of the percentage of correct response performance curves and the variability of response performance above and below interpolated threshold were related to differences between the adult and child groups (mental age) and not between types of hearing populations (hearing sensitivity). The relationship between these results and experience with the signal is speculated.

Two groups of subjects with normal hearing and three groups of subjects with noise-induced hearing loss were studied for the effect of ear protectors on word discrimination in two different speech-to-noise ratios. Various interactions in the analyses of variance were shown to be significant. The important demonstration in this study is that at high speech intensity, subjects with normal hearing should obtain higher word discrimination score with ear protectors than without if the signal-to-noise ratio is high. Albeit, the same is not true for a low signal-to-noise ratio, for a low speech intensity, or when subjects have hearing losses; the improvements in these conditions are not high enough to warrant the disuse of ear protectors. Results are discussed and compared with other studies.

This study was undertaken to investigate the effects of ear canal air pressure variation on the threshold of acoustic reflex. The acoustic reflex threshold was obtained to 500 and 1000 Hz activating signals as pressure was varied between +/- 200 mm H2O. The results demonstrated a reduction in sensitivity of the acoustic reflex with variations in positive or negative air pressure. Observation of the conductance component of admittance consistently required higher intensity levels to elicit the acoustic reflex. Clinical implications are that external air pressure can vary within a range of +/- 80 mm H2O and continue to maintain the acoustic reflex threshold close to its value obtained at maximum compliance.

This study raised the question of whether certain methods of hearing aid evaluation could predict subjects' satisfaction and willingness to use their aids. For this purpose, we compared two hearing aid evaluation methods on 30 subjects between the ages of 55 and 65 years, all of whom were hearing aid users for some months. Five signal-to-noise ratios were used. The results of this experiment indicated a significant and positive correlation between subject satisfaction and subject willingness to use the hearing aid. Results of multiple regression analyses indicated that both evaluation methods were better predictors of usage than of satisfaction.

Perilymphatic fistula, usually in the round or oval window, causes a variety of symptoms, including sensorineural hearing loss. Surgical repair of these fistulas has resulted in restoration of hearing in some cases. It has been suggested that surgery must be performed within 2 months of the trauma if improvement in hearing is to occur. This paper presents the case of a patient whose fistula and resulting hearing loss had persisted ten years before surgical repair. Restoration of normal hearing and discrimination of speech occurred in the ear which had previously presented a severe sensorineural hearing loss with no useful discrimination for speech. The authors usge audiologists and otolaryngologists to consider the possibility of fistula in cases of sudden hearing loss, even when years have elapsed since the trauma. Their experience suggests that surgery may be successful in restoring hearing after many years.

Eleven normal adults identified consonant-vowel syllables (CV's) under three conditions after extensive training in the tasks. The auditory condition consisted of the simultaneous presentation of dichotic CV's. The Auditory-Visual I condition was the presentation of dichotic CV's with the simultaneous presentation of a visual CV to both eyes. The visual CV was always the same as one of the two auditory CV's. In the Auditory-Visual II condition, the auditory dichotic and visual CV's were again presented, but the visual CV was radomly varied so that it might or might not be identical to one of the auditory CV's. No significant difference between the right and left ears were found; however, there was a slight numerical superiority, especially in the auditory condition, in favor of the right ear. The presence of a visual stimulus tended to reduce the numerical superiority so that both ears performed more nearly the same. No significant differences were found in the performance of the right ear under the 3 test conditions. The left ear performance, however, tended toward enhancement with the presentation of a noncompeting visual stimulus but was significantly reduced when the visual stimulus competed with the auditory stimulus. A similar pattern was found under a double correct data analysis. Overall auditory performance was significantly poorer than was visual performance regardless of ear or test condition. Finally, error responses were more likely to be placed of articulation errors than voicing errors.

State-wide, high-risk hearing screening is made possible in Utah through the use of a questionnaire designed for maternal response during hospitalization. The mothers of those determined high risk are sent a follow-up questionnaire when the infant is 6 to 8 months of age, and a determination is made for audiological testing on the basis of her response. Questionnaires (26352) were received on 50,700 live births, of which 4,591 (17.4%) were categorized high risk. Of the high-risk infants, 181 (3.9%) were determined at risk after follow-up, and 54 (20.8%) of these were found hearing impaired. Questionnaire item analysis is presented. Concerns regarding response validity and low return rate are discussed as is the pilot use of the birth certificate as the initial screening device.

Ascending and descending procedures were used to obtain speech reception thresholds from 32 normal-hearing subjects whereas digits and spondee words were used as test materials. Comparisons of thresholds were made for the two procedures and materials. Results indicated that slightly lower (less SPL) speech thresholds resulted from the use of a descending procedure with both types of material. In addition, digit material was found to yield generally lower threshold values than spondees. Advantages to the use of the two procedures and materials are discussed.

The intelligibility of recorded sentences, distorted by binaural switching, interruption, and low-pass filtering, was investigated in 53 children ranging in age from five to eleven and in adults. All had normal hearing. The sentence vocabulary was pretested for comprehension, articulation errors were evaluated in a way so as not to influence test results, and length and structure of the sentences were controlled. The results indicated that although the performance of children increased with age, the 11-year-old group had not attained adult performance. Error analyses showed that most errors for all age groups were acoustically unrelated to the distorted message, although adults made more acoustically related errors than did children. When children made errors in sentences, other errors (e.g., substitutions) were made to preserve the syntax or semantic integrity of the message.