Eggermont (2008) reported brain plasticity is a desirable adaptive trait, as it allows recovery from injury, life-long learning, and adaptation to changing environments.

Although human brains are usually “mostly plastic” during the first 20 years, Eggermont noted the auditory cortex demonstrates plasticity across the life-span in response to acoustically based changes such as hearing loss (how the brain is changed by listening to acoustic stimuli through impaired and altered ears), as well as wearing hearing aids and cochlear implants. In other words, plasticity invoked changes occur secondary to the occurrence of hearing loss as well as to the introduction of amplification.

Additionally, Eggermont reports long-term exposure to moderately loud sounds (even those which do not cause hearing loss) change the cortical tonotopic map. Eggermont provides evidence that plastic changes to the auditory cortex can occur in the absence of behaviorally relevant acoustic stimuli, and in children--a long-lasting absence of auditory stimulation can arrest cortical development. Eggermont reports sound is, indeed, an important factor for the organization and functioning of the auditory cortex in adults as well as in the developing child.

For More Information, Recommendations and References:
Eggermont, JJ (2008): The Role of Sound in Adult and Developmental Auditory Cortical Plasticity. Ear & Hearing. December, 2008, Vol 29, No 6.