Frequency-specific aspects of the auditory brainstem response threshold elicited by 1000-Hz filtered clicks in subjects with sloping cochlear hearing losses.

The frequency specificity of the ABR threshold evoked by a 1000-Hz filtered click was determined in subjects with sloping cochlear hearing losses, both high- and low-frequency in character. The results show that the ABR threshold evoked by this stimulus is low-frequency specific. The standard error in estimating the 1000-Hz pure-tone threshold (PTT) is 10.

Comparison between the frequency specificities of auditory brainstem response thresholds to clicks with and without high-pass masking noise.

In this study, the frequency specificity of the auditory brainstem response (ABR) threshold to a click masked with 1590-Hz high-pass masking noise is compared with the frequency specificity of the unmasked click-evoked ABR threshold. The ABR threshold to the high-pass-noise-masked click stimulus is low frequency specific and corresponds with the 1,000-Hz pure-tone threshold. Although the ABR threshold to the unmasked click stimulus corresponds with the '3,000'-Hz pure-tone threshold, the frequency specificity seems much less pronounced than that of the low-frequency-specific stimulus.

Low-frequency specificity of the auditory brainstem response threshold elicited by clicks masked with 1590-Hz high-pass noise in subjects with sloping cochlear hearing losses.

In this study, the frequency specificity of the ABR threshold to stimulation with a click masked with 1590-Hz high-pass noise was determined in subjects with sloping cochlear hearing losses both high- and low-frequency in character. The results show that the ABR threshold elicited by this stimulus is low-frequency specific. The standard error in estimating the 1,000-Hz pure-tone threshold from the high-pass-noise-masked click-evoked ABR threshold is 10.

Monaural versus binaural auditory brainstem response threshold to clicks masked by high-pass noise in normal-hearing subjects.

Monaural and binaural auditory brainstem response (ABR) thresholds to clicks masked by high-pass noise with a cut-off frequency of 1,590 Hz were measured in normal-hearing subjects. In sleeping normal-hearing subjects, the 1,000-Hz frequency-specific ABR threshold for binaural stimulation amounted to 12 dB nHL and for monaural stimulation to 18 dB nHL. No significant difference in latency was found between monaural and binaural stimulation.

Frequency specificity of the auditory brainstem response elicited by 1,000-Hz filtered clicks.

In normal-hearing subjects and in subjects with a flat cochlear hearing loss, auditory brainstem responses (ABR) were recorded at various levels of a 1,000-Hz filtered click stimulus with and without high-pass filtered masking noise. The difference in latency of the major peak in the ABR for the masked and unmasked condition was zero at the ABR threshold. We regard this as proof of the frequency specificity of the 1,000-Hz filtered click-stimulated ABR threshold.

Conductive hearing loss assessment in children with otitis media with effusion. A comparison of pure tone and BERA results.

A comparison between pure-tone audiometry and brainstem electric response audiometry was made in 25 children with a conductive hearing loss due to otitis media with effusion. Pure-tone audiometry, including bone and air-conduction thresholds, was recorded using standard procedures. BERA was used to construct a latency-intensity function and from this the conductive hearing loss could be estimated.

Development of cis-platinum-induced hearing loss in guinea pigs.

The resultant hearing loss can be variable if cis-dichlorodiammineplatinum is given to guinea pigs. In order to find out more about these differences, we used brainstem audiometry to study the start and development of hearing loss over time for several frequencies. Our results confirmed previous observations that hearing loss starts at the higher frequencies but can also occur at lower frequencies.

Analysis of hearing loss due to cis-diamminedichloroplatinum-II.

The difference in the hearing threshold before and after treatment with cis-diaminnedichloroplatinum (DDP) is analysed in 69 patients. Hearing loss due to DDP treatment is mainly limited to 8,000 Hz and the incidence is about 40%. The effect of DDP is dose-related, although even at the lowest dose 20% of the patients are affected.

Pattern of gentamicin-induced cochlear degeneration in the guinea pig. A morphological and electrophysiological study.

Gentamicin-induced cochlear degeneration in the guinea pig was studied by complete hair-cell counting (cytocochleograms) and phase-contrast and interference microscopical examination of the stria vascularis and Reissner's membrane. Gentamicin (100 mg/kg/day) was administered over a period of 7-17 days. The first loss of hair cells (OHC) occurred in a region 6-8 mm from the round window.