Auditory Brainstem Response Peak Latencies Research Articles

Audiovestibular Dysfunction in Siblings with Charcot-Marie-Tooth Disease 4F: A Case Series.

Charcot-Marie-Tooth disease type 4F (CMT4F) is an autosomal recessive disorder with symptoms presenting in early adulthood. This clinical case series demonstrates atypical findings in cervical and ocular vestibular evoked myogenic potentials (VEMP) in siblings with CMT4F. The aim of this study was to highlight the audiovestibular test findings in CMT4F. Case series study sample: 4 siblings, 3 of whom diagnosed with CMT4F. Audiological test battery and electrophysiological tests comprising auditory brainstem response (ABR) and VEMP (both cervical and ocular) were performed in our patient population. Older siblings, in whom the hearing loss was present, manifested prolonged peak V latencies in ABR. Three out of four siblings with CMT4F showed prolongation of latencies on cervical and ocular VEMP. In many neurodegenerative conditions, prolongation of ABR peak latencies has often been reported in the literature. There have also been a few reports of prolonged VEMP peak latencies. This article reports prolongation of only VEMP peak latencies (in both cervical and ocular recordings). The youngest sibling had prolongation of VEMP latencies, with ABR peak latencies being normal. The assumption we put forth that CMT4F may affect the vestibular pathway first requires to be tested on a larger sample and by longitudinally studying the individuals with disease condition.

Study of effect of chronic suppurative otitis media on auditory brainstem response latency

<p class="abstract"><strong>Background:</strong> Chronic suppurative otitis media (CSOM) emerging as common hearing problems in the recent years with high prevalence requiring immediate attention. Hence, our study includes assessment of adult patients with CSOM using electrophysiological test, auditory brainstem response (ABR) and analysing the latency of ABR peaks in order to find the effect of CSOM on ABR latency with respect to shift in latency.</p><p class="abstract"><strong>Methods:</strong> The study followed cross sectional study design where data collected from March to September 2019 were used. A total of 50 subjects with unilateral CSOM were analysed. Descriptive statistics and paired t-test was used for statistical analysis of the data. </p><p class="abstract"><strong>Results:</strong> The data was divided into 3 groups based on degree of hearing loss (mild, moderate and moderately severe). The Mean ABR peak latency was analysed and subjects showed a significant latency shift. Also, it was found that the magnitude of latency shift increased with increase in degree of hearing loss.</p><p class="abstract"><strong>Conclusions:</strong> Hence the study concludes that as the amount of conductive component increases the pure tone threshold deteriorates and ABR latency gets affected. Also, the morphology of ABR peaks on comparison to the normal hearing ear gets affected due to constant conductive pathology in the pathological ear.</p><p class="abstract"> </p>

Effects of stimulus cosine onset properties on bottlenose dolphin (Tursiops truncatus) auditory brainstem responses.

Although the auditory brainstem response (ABR) is known to be an onset response, the specific relationship between stimulus onset properties and the resulting ABR is not well understood. In this study, the effects of stimulus onset on dolphin ABR were examined by measuring ABRs in six bottlenose dolphins while systematically manipulating rise time and plateau sound pressure of cosine-enveloped noise bursts. Noise bursts were spectrally "pink" with frequency content from 10 to 160 kHz, rise times from 32 μs to 4 ms, and plateau sound pressure levels from 102 to 138 dB re 1 μPa. Envelope rise time and plateau sound pressure alone were found to be poor predictors for ABR peak amplitudes and latencies. Peak amplitudes were well described by the envelope sound pressure at the end of a 260-μs window; however, best-fits to the data across ABR peaks were obtained when the window start time was allowed to vary. Peak latencies were best described by the maximum value of the second derivative of the pressure envelope. These results are consistent with single-unit and nearfield response data for terrestrial mammals and indicate that stimuli with rise times greater than 260 μs are non-optimal with respect to maximizing ABR amplitudes.

Neural correlates of sound-learning experiences in the auditory system: Translational candidates for hearing rehabilitation

A major disconnect between traditional auditory perception research and recent neuroscience is the high propensity in the auditory system for neuroplasticity. Altered processing of reward-associated sound stimuli can contribute to adaptive behavior, such as hearing, listening, and attending appropriately to sound cues. I will the present work from animal models of learning-induced neuroplasticity in the cortical and subcortical auditory system. The data show how receptive fields and tonotopic maps in primary auditory cortex (A1) as well as the auditory brainstem response (ABR) can change when adult animals trained by pairing a tone with the availability to obtain reward alters sound coding in the auditory system. Over the course of conditioning, increases and reductions, respectively, in ABR amplitude and peak latencies predict how well animals can pick out the learned sound-frequency acoustic cue from other frequencies following conditioning. Furthermore, receptive fields in A1 have narrower tuning for a remembered sound frequency—and only in animals who successfully remember that frequency over others assessed by behavioral test. Therefore, learned sounds are preferentially processed over novel and distractor sounds following conditioning. Significant behavioral preferences for learned tones may be due, in part, to the observed changes in auditory processing across the auditory system.

Dependence of bottlenose dolphin (Tursiops truncatus) auditory brainstem responses on noise burst rise time, amplitude, and envelope shape

A series of experiments examined the dependence of dolphin auditory brainstem response (ABR) peak amplitudes and latencies by stimulus level, rise times, and envelope shape. Stimuli were spectrally “pink” noise bursts with frequency content from 10 to 160 kHz, rise times that varied from 32 μs to 4 ms, and plateau sound pressure levels from 102 to 138 dB re 1 μPa. Cosine and cosine-cubed rise (and fall) envelopes were tested, and results were compared to those obtained for dolphins using noise bursts with linear rise envelopes [Finneran et al., J. Acoust. Soc. Am. 143, 2914–2921 (2018)]. Results for the cosine and cosine-cubed envelopes showed that ABR peak amplitudes were a function of envelope sound pressure at the end of a fixed integration window of approximately 260 μs. This is congruent with the previous findings for linear envelopes. The ABR peak latencies for the cosine and cosine-cubed envelopes were dependent on the second derivative of the envelope pressure function, as opposed to the first derivative of the pressure function for linear envelopes. These data are consistent with single-unit and nearfield response data for terrestrial mammals. [Work supported by Navy Living Marine Resources and SSC Pacific Naval Innovative Science and Engineering Programs.]

Effects of noise burst rise time and level on bottlenose dolphin (Tursiops truncatus) auditory brainstem responses.

Although the auditory brainstem response (ABR) is known to be an onset response, specific features of acoustic stimuli that affect the morphology of the ABR are not well understood. In this study, the effects of stimulus onset properties were investigated by measuring ABRs in seven bottlenose dolphins while systematically manipulating stimulus rise time and the amplitude of the sound pressure temporal envelope plateau. Stimuli consisted of spectrally pink (i.e., equal mean-square pressure in proportional frequency bands) noise bursts with linear rise (and fall) envelopes and frequency content from 10 to 160 kHz. Noise burst rise times varied from 32 μs to 4 ms and plateau sound pressure levels varied from 96 to 150 dB re 1 μPa. ABR peak latency was found to be a function of the rate of change of the sound pressure envelope, while ABR peak amplitude was a function of the envelope sound pressure at the end of a fixed integration window. The data support previous single-unit and nearfield response data from terrestrial mammals and a model where the rate of change of envelope sound pressure is integrated across a time window aligned with stimulus onset.

The effects of click and masker spectrum on the auditory brainstem response of bottlenose dolphins (Tursiops truncatus).

Two experiments were performed that investigated the effects of (1) click level and (2) continuous broadband noise on the binaural auditory brainstem response (ABR) of normal-hearing and hearing-impaired bottlenose dolphins (Tursiops truncatus). In addition to spectrally uncompensated clicks and noise, stimuli were digitally compensated to achieve "white" spectra (flat spectral density level) or "pink" spectra (spectral density level rolling off at -3 dB/octave). For experiment 1, in all spectral conditions, ABR peak latencies increased and peak amplitudes decreased with decreasing click level, but interwave intervals changed little. Latency-intensity function (LIF) slopes ranged from -3 to -11 μs/dB. The LIF slopes of ABR peaks evoked by uncompensated clicks were steeper in dolphins with hearing loss. Click level was held constant during experiment 2, and the effect of bilaterally delivered broadband masking noise on the ABR was investigated. Clicks and noise were filtered to create a pink click/noise condition and a white click/noise condition. With increasing levels of masking noise, peak latencies increased (although only P1-P4 white reached significance), peak amplitudes decreased, and interpeak intervals increased (although not significantly). These effects are compared to results reported for terrestrial mammals, and implications for auditory health assessment and biosonar function are discussed.

The Physiological Basis and Clinical Use of the Binaural Interaction Component of the Auditory Brainstem Response.

The auditory brainstem response (ABR) is a sound-evoked noninvasively measured electrical potential representing the sum of neuronal activity in the auditory brainstem and midbrain. ABR peak amplitudes and latencies are widely used in human and animal auditory research and for clinical screening. The binaural interaction component (BIC) of the ABR stands for the difference between the sum of the monaural ABRs and the ABR obtained with binaural stimulation. The BIC comprises a series of distinct waves, the largest of which (DN1) has been used for evaluating binaural hearing in both normal hearing and hearing-impaired listeners. Based on data from animal and human studies, the authors discuss the possible anatomical and physiological bases of the BIC (DN1 in particular). The effects of electrode placement and stimulus characteristics on the binaurally evoked ABR are evaluated. The authors review how interaural time and intensity differences affect the BIC and, analyzing these dependencies, draw conclusion about the mechanism underlying the generation of the BIC. Finally, the utility of the BIC for clinical diagnoses are summarized.

Age-Related Maturation of Wave V Latency of Auditory Brainstem Response in Children.

Background and ObjectivesAuditory brainstem response (ABR) is a noninvasive measurement of a stimulus-locked, synchronous electrical event. ABR provides information concerning the functional integrity of brainstem nuclei. Age is a key factor in the interpretation of ABR peak latency among different age groups. Progressively with time it follows a "maturation pattern" during which latencies decrease. Wave V is very prominent and reliable for detection of threshold in children. The present study was performed to see the effect of age related auditory maturation on ABR wave V latency in children.Subjects and MethodsThe study involved 80 subjects ranging in age from birth to 12 years. The subjects were divided equally into eight age groups. ABR were elicited by an acoustic click stimuli, brainstem responses collected through electrode and recorded at the same time. Latency of wave V was acknowledged.ResultsWave V latency decreased rapidly in early childhood, became slower after 3 years of age and completely matured by 12 years of age. There was no significant difference in latency of wave V between the ears with age.ConclusionsThere is a distinct maturation pattern of wave V latency in ABR for both ears. ABR is a reliable test to assess the functional maturation of wave V in children.

The modulation rate transfer function of a harbour porpoise (Phocoena phocoena)

During echolocation, toothed whales produce ultrasonic clicks at extremely rapid rates and listen for the returning echoes. The auditory brainstem response (ABR) duration was evaluated in terms of latency between single peaks: 5.5 ms (from peak I to VII), 3.4 ms (I-VI), and 1.4 ms (II-IV). In comparison to the killer whale and the bottlenose dolphin, the ABR of the harbour porpoise has shorter intervals between the peaks and consequently a shorter ABR duration. This indicates that the ABR duration and peak latencies are possibly related to the relative size of the auditory structures of the central nervous system and thus to the animal's size. The ABR to a sinusoidal amplitude modulated stimulus at 125 kHz (sensitivity threshold 63 dB re 1 μPa rms) was evaluated to determine the modulation rate transfer function of a harbour porpoise. The ABR showed distinct envelope following responses up to a modulation rate of 1,900 Hz. The corresponding calculated equivalent rectangular duration of 263 μs indicates a good temporal resolution in the harbour porpoise auditory system similar to the one for the bottlenose dolphin. The results explain how the harbour porpoise can follow clicks and echoes during echolocation with very short inter click intervals.

Age-related changes in the auditory brainstem response.

This cross-sectional study had two goals: (1) Identify and quantify the effects of aging on the auditory brainstem response (ABR); (2) Describe how click rate and hearing impairment modify effects of aging. RESEARCH DESIGN AND ANALYSIS: ABR measures were obtained from 131 predominately male Veteran participants aged 26 to 71 yr. Metrics analyzed include amplitude and latency for waves I, III, and V, and the I-V interpeak latency interval (IPI) at three repetition rates (11, 51, and 71 clicks/sec) using both polarities. In order to avoid confounding from missing data due to hearing impairment, participants had hearing thresholds <40 dB HL at 2 kHz and 70 dB HL at 4 kHz in at least one ear. Additionally, the median 2, 3, and 4 kHz pure tone threshold average (PTA2,3,4) for the sample, ∼17 dB HL, was used to delineate subgroups of better and worse hearing ears, and only the better hearing sample was modeled statistically. We modeled ABR responses using age, repetition rate, and PTA2,3,4 as covariates. Random effects were used to model correlation between the two ears of a subject and across repetition rates. Inferences regarding effects of aging on ABR measures at each rate were derived from the fitted model. Results were compared to data from subjects with poorer hearing. Aging substantially diminished amplitudes of all of the principal ABR peaks, largely independent of any threshold differences within the group. For waves I and III, age-related amplitude decrements were greatest at a low (11/sec) click rate. At the 11/sec rate, the model-based mean wave III amplitude was significantly smaller in older compared with younger subjects even after adjusting for wave I amplitude. Aging also increased ABR peak latencies, with significant shifts limited to early waves. The I-V IPI did not change with age. For both younger and older subjects, increasing click presentation rate significantly decreased amplitudes of early peaks and prolonged latencies of later peaks, resulting in increased IPIs. Advanced age did not enhance effects of rate. Instead, the rate effect on wave I and III amplitudes was attenuated for the older subjects due to reduced peak amplitudes at lower click rates. Compared with model predictions from the sample of better hearing subjects, mean ABR amplitudes were diminished in the group with poorer hearing, and wave V latencies were prolonged. In a sample of veterans, aging substantially reduced amplitudes of all principal ABR peaks, with significant latency shifts limited to waves I and III. Aging did not influence the I-V IPI even at high click rates, suggesting that the observed absolute latency changes associated with aging can be attributed to changes in auditory nerve input. In contrast, ABR amplitude changes with age are not adequately explained by changes in wave I. Results suggest that aging reduces the numbers and/or synchrony of contributing auditory nerve units. Results also support the concept that aging reduces the numbers, though perhaps not the synchrony, of central ABR generators.

Auditory brainstem responses in adult budgerigars (Melopsittacus undulatus).

The auditory brainstem response (ABR) was recorded in adult budgerigars (Melopsittacus undulatus) in response to clicks and tones. The typical budgerigar ABR waveform showed two prominent peaks occurring within 4 ms of the stimulus onset. As sound-pressure levels increased, ABR peak latency decreased, and peak amplitude increased for all waves while interwave interval remained relatively constant. While ABR thresholds were about 30 dB higher than behavioral thresholds, the shape of the budgerigar audiogram derived from the ABR closely paralleled that of the behavioral audiogram. Based on the ABR, budgerigars hear best between 1000 and 5700 Hz with best sensitivity at 2860 Hz-the frequency corresponding to the peak frequency in budgerigar vocalizations. The latency of ABR peaks increased and amplitude decreased with increasing repetition rate. This rate-dependent latency increase is greater for wave 2 as indicated by the latency increase in the interwave interval. Generally, changes in the ABR to stimulation intensity, frequency, and repetition rate are comparable to what has been found in other vertebrates.

Effects of tone burst frequency and intensity on the auditory brainstem response (ABR) from albino and pigmented rats

Young adult male Sprague-Dawley (SC) and Long-Evans (LE) rats were evaluated using the auditory brainstem response (ABR). ABRs were evoked by stimuli with intensities ranging from 15 to 100 dB peSPL. Stimuli were tone bursts of 2000, 4000 and 8000 Hz. As stimulus intensity decreased from 100 to 15 dB, the ABR peak latencies prolonged, interpeak latencies (IPLs) shortened and amplitudes decreased. As stimulus frequency decreased from 8000 to 2000 Hz, ABR latencies prolonged, amplitudes decreased and ABR thresholds increased. The longest IPLs were in response to the 4000 Hz tone bursts. SD rats had ABRs with shorter peak latencies, larger amplitudes and lower thresholds than LE rats. The IPLs usually did not show significant strain-dependent differences. Our observations on stimulus intensity and frequency are consistent with previous reports. Our observations also suggest that the SD (albino) rat has better auditory acuity than the LE (pigmented) rat over the frequency range of 2000 to 8000 Hz. This implies that previous concerns about the use of albino animals in audiological research are somewhat overstated.

Dependence of auditory brainstem response on click polarity and high-frequency sensorineural hearing loss.

An investigation is presented on the effect of click polarity upon the auditory brainstem response (ABR) in cases of simulated high-frequency hearing loss. A high-frequency hearing loss was stimulated in 12 normal subjects by applying a high-pass noise masker, the noise cutoff frequency being varied in half-octave steps through the range of audiometric frequencies. With this paradigm, the effects of click polarity on the ABR are similar to those reported in patients with high-frequency hearing loss, including changes in waveform morphology and substantial peak latency shifts. To evaluate the role of individual cochlear frequency channels in a more direct way, half-octave narrow-band responses were determined by pair-wise subtraction of the high-pass-noise-masked responses. As far as ABR peak latencies are concerned, stimulus polarity effects tend to increase towards the lower frequency bands. Thus, the selective elimination of the contribution to the ABR of cochlear high-frequency channels can be held responsible for the increased dependence of ABR on click polarity observed in high-frequency hearing loss. However, statistical evaluation of peak I, III and V latencies, both in high-pass-noise-masked and in narrow-band ABRs, reveals that the latency effects are not systematic between subjects. Mechanisms producing the observed rarefaction-condensation differences, possible explanations for the large intersubject variability and the consequences for clinical interpretation of ABR are discussed.

The 3-channel Lissajous' trajectory of the auditory brain-stem response. IV. Effects of electrode position in the cat

Three-channel Lissajous' trajectories (3-CLTs) of the auditory brain-stem response (ABR) were recorded from anesthetized adult cats with 2 different orthogonal and 3 different non-orthogonal recording configurations. Click stimuli were presented monaurally at 70 dB impulse SPL. Planar analysis identified 12 planar segments regardless of electrode configurations. Boundaries, apex latencies, and durations of the planar segments were relatively unchanged by changes in recording locations, in contrast to changes in single-channel ABR peak latencies and amplitudes. The 3-CLT orientation and shape were maintained in voltage-space despite changes in electrode positions, provided that the recording axes remained orthogonal and a simple cosine correction was applied. Non-orthogonal recording axes resulted in 3-CLTs which differed in shape from 3-CLTs recorded from orthogonal recording axes, but had similar planar-segment boundaries and durations. We conclude that the 3-CLT has characteristics which are generator-dependent and unaffected by electrode position if appropriate spatial corrections are applied.