1. Introduction

Hearing is one of the primary means of human contact with the world, from the perception of acoustic signals that indicate danger through an alert system to the development of language and intellect. In the evolutionary process, the human auditory system underwent transformations that enabled it to capture, amplify (magnify), perceive, and discriminate sound, the last two achieved from the inner ear (cochlea) to the auditory cortex.

3. Hearing losses

and adults alike [6, 7].

spectral selectivity.

hearing thresholds.

3.1. Noise-induced hearing loss

with a daily sound source [4, 5].

Over the centuries, man has advanced in a number of ways, but this progress has also

Hearing Loss at High Frequencies and Oxidative Stress: A New Paradigm for Different Etiologies

http://dx.doi.org/10.5772/intechopen.76325

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Exposure to high levels of sound pressure (noise), both professionally and at leisure, can cause irreversible hearing loss, which is often progressive when an individual remains in contact

Increased life expectancy means age-related hearing loss (presbycusis) has become more com-

The emergence of new drugs has led to the cure of numerous hitherto lethal diseases; however, the ototoxic effect of certain medications causes hearing loss and leaves sequelae in children

Chronic kidney disease (CKD), which has multiple etiologies, can evolve with progressive hearing loss, representing yet another disability for kidney patients and compromising their quality of life. Moreover, the use of certain drugs for patients with CKD may worsen auditory

These hearing disorders exhibit a sensorineural pattern due to the sites affected, which vary from the cochlea to the auditory cortical regions, with a preference for high sound frequencies. However, high-frequency damage is a starting point, and 4 kHz is seen as the border between

Assessment of the physiopathological model of these hearing losses shows that oxidative stress occurs under all the aforementioned conditions and emerges as a new paradigm that more deeply connects characteristic acoustic aspects common to all of them. The real reason for which hearing loss arises, preferentially and usually around 4 kHz, is not fully understood, but there may be a common point in molecular and physiopathological terms that leads to this

Starting with a model that considers oxidative stress, we will discuss each of the hearing loss conditions influenced by excess free radicals and expressed by an increase in high-frequency

Excessive exposure to noise induces sensorineural hearing loss resulting from damage to cochlear and neural structures in the inner ear, denominated NIHL. NIHL can be temporally classified into two types: hearing loss induced by chronic noise and acute acoustic trauma. Chronic NIHL is a hearing deficiency caused by continuous exposure to high levels of sound pressure that exert an average of 90 dBA, for eight hours a day, over several years or more [4], whereas acute acoustic trauma is hearing loss caused by short exposure to excessively loud

introduced lifestyle habits that sometimes cause new risk factors for hearing loss.

mon and is one of the most prevalent chronic diseases worldwide.

function and be an aggravating factor for hearing loss [8].

frequencies that often remain preserved and those affected.

sounds (100–150 dBA, decibel weighting curve A) [9].

Human hearing perceives sounds ranging from 20 Hz to 16 kHz, and exhibits tonotopy from the cochlea to the auditory cortex, such that hearing frequencies are recognized in an organized manner along the auditory pathway. Under certain conditions that lead to hearing loss, initial and selective damage may occur at certain sound frequencies. This pattern of selective damage can be observed in a number of pathological conditions whose physiopathological foundation may be based on an oxidative stress model. Among these conditions are noiseinduced hearing loss (NIHL), age-related hearing loss (presbycusis), ototoxic hearing loss, and hearing loss associated with chronic kidney disease (CKD).
