摘要:

Previous research found a relationship between stress-prone personality (pattern A) and noise-induced vasoconstriction in normal-hearing adult subjects. The present research sought evidence for a possible relationship between susceptibility to high-frequency noise-induced permanent threshold shift (NIPTS) found among industrial workers and the vasoconstrictive behavior of the same workers when they were exposed to high-intensity noise. It was hypothesized that pattern A workers would show more vasoconstriction in the presence of high-intensity noise, and hence more susceptibility to NIPTS, than pattern B (non-stress-prone) workers. The 35 male subjects tested were divided into two groups. Group I contained 16 subjects who showed significant vasoconstriction in noise; group I subjects were clearly pattern A types. Group II contained 19 subjects who did not show significant vasoconstriction in noise. Group II contained mostly pattern B but a few pattern A subjects. Unexpectedly, it was the group II subjects who showed the most susceptibility to NIPTS; the difference between the means of the two groups was statistically significant (p 2 0.001). The explanation for this unexpected finding is obscure.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

The relationships among a personality measure, peripheral vascular measures, and audiometric indexes of susceptibility to noise-induced hearing loss were studied. Seventy-four male human subjects were selected based upon their responses to a self-report measure of coronary-prone behaviors. Coronary-prone, nonprone, and median scores with normal hearing were included in the study. The audiometric measures were 4 kHz pure-tone thresholds, 4 kHz acoustic reflex thresholds, and thresholds of octave masking. Subjects were exposed to 5 min of either 110 dB SPL or 20 dB SPL white noise designated loud and soft noise, respectively. Temporary threshold shifts were assessed at three intervals after the noise exposure (0.25, 2, and 10 min). Blood pressure was assessed before the noise exposure. Digital and cephalic vasoconstriction were measured throughout the procedures. The results indicated that coronary-prone persons were significantly more likely to fail the pure-tone screening but did not differ from others on any additional measure. Temporary threshold shifts were negatively correlated with resting level blood pressure, vasoconstriction, and thresholds of octave masking.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

This investigation was designed to: (1) collect normative data on a commercially available recording of the Synthetic Sentence Identification (SSI) test mixed with a four-talker (FT) competitor at several message-to-competition ratios (MCRs), and (2) assess the effects of practice on SSI-FT performance at each MCR. Sixteen normal-hearing subjects responded to a total of 140 sentences during four trials at MCRs ranging from −6 to +4 dB. The results showed a marked learning effect, especially at the more favorable MCRs; approximately 60 practice sentences were required to ensure stable SSI scores. The clinical implications of these findings are discussed.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Auditory abnormalities were evaluated in human albinos using temporary threshold shift and dichotic listening tasks. Albinos exhibited a greater temporary threshold shift than did normally pigmented individuals after exposure to a fatiguing tone. In the dichotic listening task, albinos demonstrated a significantly larger right ear advantage than normally pigmented individuals. These results support earlier work indicating that hemispheric asymmetries are present in the albino auditory system and suggest that abnormalities may be present at the cochlear level as well.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Subjects (N = 130) employed in similar noise environments were given standard audiometric threshold evaluations. Their melanin content, as inferred from their eye color, was noted. The hearing thresholds of “dark-eyed.” “medium-eyed,” and “light-eyed” subjects were subjected to statistical analysis. Analysis of variance revealed mean threshold differences at 4 and 6 kHz. However, no significant mean threshold differences between eye color groups were seen when mean thresholds were adjusted for years of exposure in a covariance design. It is concluded that although there is a modest relationship between eye color (melanin content) and susceptibility to noise-induced hearing loss, this relationship is less apparent in populations exposed to noise levels below 110 dB (re HTL).

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Different types of hearing aid test equipment use different methods to calculate total harmonic distortion (THD). Comparisons of the THD measured by four commercially available systems were made by evaluating eight hearing aids, three times each. The results obtained were significantly different (p <0.001) among three of the test instruments. Furthermore approximately 10% of the hearing aids, which met the ANSI S3.22–1976 specifications for THD when tested with an apparatus that measures true THD, failed this measurement when evaluated on the other three systems.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Acoustic reflex threshold and magnitude were measured for normal-hearing subjects in four experiments under conditions of: (1) tight and relaxed eyelid closure; (2) eyes open and closed in light, focusing on a spot, reading, and solving a visual maze; (3) tactile stimulation; and (4) performing a mental task. Measurements were susceptance change in millimhos for a 220 Hz probe tone. A 1000 Hz pure-tone and broadband noise presented contralaterally were the stimuli. All factors affected reflex results. Eyelid closure enhanced reflex responses with tight closure involving voluntary muscle tension having a greater effect than relaxed closure. Both passive and active visual tasks suppressed the reflex. The mental task resulted in suppression of both reflex threshold and magnitude. Vibrotactile stimulation also resulted in a suppressed reflex. Changes were more pronounced with broadband noise as the reflex eliciting stimulus. Clinical implications are discussed.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

This investigation determined the relative merit of four different hearing aid/telephone coupling systems. Speech recognition measures and quality preferences by magnitude estimation were used to evaluate the systems. Neither speech recognition testing nor magnitude estimation results revealed one particular hearing aid/telephone coupling system that was superior for all 10 subjects. A procedure is described in which consideration of both discrimination and quality estimation results can be used to provide specific recommendations for individual patients. However, the communication needs of some people may require the use of more than one type of system.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Differences in gain usage based upon hearing aid experience and wearer's age were examined from records of 344 monaural fittings with closed earmolds. No pattern of gain usage difference was found among hearing aid experience categories or client age categories. For 79% of the individuals, using gain was within 6 dB of that which was predicted.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID