Letter to the Editor

Abstract

Lee et al. (2005) misquoted our hypothesis (Gates et al. 2000) and, not unexpectedly, differed in their conclusion about the effect of noise on cochlear aging. We described actual shifts in noise-damaged ears and found a significant effect. In contrast, Lee et al. (2005) described predicted shifts in noise-exposed ears and found a similar pattern albeit not statistically significant. Although these are different concepts, the similarity in the primary graphs in both reports (Figures 1 and 2) suggests a substantial degree of parallelism.A convincing case can be made that if Lee et al. (2005) had simply followed their subjects longer and had an adequate sample size, their conclusions would have been similar to ours. We had an IS year, not a 6.4-yr follow-up and nearly twice the sample size. Moreover, few of their cases had audiometric evidence of noise damage. Thus, their conclusion that noiseexposed ears do not age differently than nonexposed ears may be underpowered and premature.We look forward to a re-evaluation of their cases after longer follow-up and predict that their data will support ours despite the difference in experimental design. We clearly showed that noise-damaged ears do change with age in adjacent frequency regions differently than nondamaged ears.

Age-related hearing decline in individuals with and without occupational noise exposure

“…Gates et al . [ 9 17 ] reported that frequencies adjacent to supposed noise notches exhibit an accelerated annual decline, compared to the same frequencies measured in individuals with no such notches. We found no support for this concept, provided that these dips reflect NIHL, which has been called into question.…”

Functional Role of Neurotrophin-3 in Synapse Regeneration by Spiral Ganglion Neurons on Inner Hair Cells after Excitotoxic TraumaIn Vitro

“…In humans (Gates et al, 2000) and mice (Kujawa and Liberman, 2006, 2009) exposure to noise while young, even at a level that does not compromise hair cells, is associated with accelerated age-related hearing loss in the aging individual, indicating that deleterious effects of noise continue long after the exposure has ended (Gates, 2006). In noise-exposed mice, accelerated age-related hearing loss was associated with increased SGN death (Kujawa and Liberman, 2006, 2009).…”