hearing loss

Mammals lost the ability to recover from hearing loss

Noise-induced hearing loss (NIHL) is hearing decrease caused by loud sound. Evidences of NIHL include a history of exposure to loud sound and a hearing loss in a narrow range of frequencies, such as those from gunfire, power tools, explosions and night club music. The best, first option for protecting hearing is lowering the volume at the source of the sound.

Currently, hearing loss in mammals is permanent. While frogs, fish, and birds with hearing loss regain their hearing naturally, mammals lost that ability as much as 300 million years ago, and so far scientists have been unsuccessful in solving that problem.


NIHL can easily be prevented through the use of some of the most simple, widely available and economical tools. This includes but is not limited to ear protection (i.e. earplugs and earmuffs), education, and hearing conservation programs. Earplugs and earmuffs can provide the wearer with at least 5 to 10 dB SPL of attenuation. According to a survey by Lass, Woodford, C. Lundeen, D. Lundeen and Everly-Myers, which examined high school student’s attitudes and knowledge concerning hearing safety, 66% of the subjects reported a positive response to wearing hearing protection devices if educated about NIHL. Unfortunately, more often than not, individuals will avoid the use of ear protection due to embarrassment, lack of comfort, and reduced sound quality.

Hearing protection programs have been hindered by people not wearing the protection for various reasons, including the desire to converse, uncomfortable devices, lack of concern about the need for protection, and social pressure against wearing protection.


A systematic review of the effectiveness of interventions to promote the use of hearing protection devices such as earplugs and earmuffs among workers found that tailored interventions improve the average use of such devices when compared with no intervention. (Tailored interventions involve the use of communication or other types of interventions that are specific to an individual or a group and aim to change behavior). Mixed interventions such as mailings, distribution of hearing protection devices, noise assessments, and hearing testing are also more effective in improving the use of hearing protection devices compared with hearing testing alone.