The Relationship between Loudness Intensity Functions and the Click-ABR Wave V Latency

Abstract

The results of this study established a relationship between loudness and the ABR wave V latency for listeners with normal hearing, and flat cochlear hearing loss. In listeners with a sloping configuration of cochlear hearing loss, the relationship was not significant. This suggests that the click-evoked ABR may be used to estimate loudness growth at least for individuals with normal hearing and those with a flat configuration of cochlear hearing loss. Predictive equations were derived to estimate loudness growth for these groups. The use of frequency-specific stimuli may provide more precise information on the nature of the relationship between loudness growth and the ABR wave V latency, particularly for listeners with sloping configurations of cochlear hearing loss.

Understanding hearing impairment through model predictions of brainstem responses

“…When plotted as a function of dB SPL, only a small shift (0.2 ms) towards shorter latencies in the ABR wave-I latency-with-level curve was observed in another study of chinchillas with noise-induced hearing loss (Henri et al, 2011). In agreement with these findings, similar latencywith-level slopes for human ABR wave-V were found for a normal-hearing group and a group with a flat sensorineural hearing loss (Serpanos et al, 1997). However, in contrast to linear filter theory, the hearing-impaired and normal-hearing groups showed similar latency values.…”

Estimating loudness growth from tone-burst evoked responses

“…Several studies have attempted to find a relationship between ABR and loudness growth as a function of level ͑Pratt and Sohmer, 1977;Wilson and Stelmack, 1982;Babkoff and Pratt, 1984;Davidson et al, 1990;Serpanos et al, 1997;Gallego et al, 1999͒. ͑See Table I for a detailed summary.͒ A few patterns can be observed from the list of studies that investigated ABR and loudness growth.…”

“…Despite this well known characteristic of noise in ABR recordings, no attempt was made to control or quantify the ABR residual-noise 1 power as a function of stimulus level in any of these studies. Although, for example, Serpanos et al ͑1997͒ did apply an artifact rejection threshold, this does not guarantee that the residual noise levels are equal across all stimuli levels. Controlling for, or reporting, the residual noise levels can be valuable in determining a minimum quality level for an accurate estimation ͑possibly reducing the number of required trials͒, and in understanding the effects of this confounding variable in the estimation of loudness growth from ABR.…”

Objective estimation of loudness growth in hearing-impaired listeners

“…The two point estimates used were the average RMS and the maximum amplitude squared. The maximum amplitude squared was chosen due to the use of Wave V amplitude for loudness estimation in previous literature (Pratt and Sohmer, 1977;Wilson and Stelmack, 1982;Babkoff et al, 1984;Davidson et al, 1990;Serpanos et al, 1997;Gallego et al, 1999).…”

“…While this method showed promising results in normal listeners, it was not clear if the performance of the loudness growth estimation technique would be accurate and robust enough to use for estimating loudness growth for a diverse group of HILs. In particular, studies looking into loudness growth and TBABRs have yielded mixed conclusions (Pratt and Sohmer, 1977;Wilson and Stelmack, 1982;Babkoff et al, 1984;Davidson et al, 1990;Serpanos et al, 1997;Gallego et al, 1999), the TBABR measurement variability and residual noise levels being a major source of contention. The Silva and Epstein (2010) method however, attempts to control for part of the variability in the recorded TBABR through the use of the Non-Stationary Fixed-Multiple-Point (NS Fmp) statistic for measuring residual noise levels (see Silva, 2009 for review).…”