Answer the following questions:

• What is the normal range of human hearing, and how does this range change with age?
• Human ear can perceive frequencies anywhere from 20 Hz (lowest pitch) to 20 kHz (highest pitch). Each sound lower than 20 Hz remains qualified as infrasound’s, although some animals (ex. mole-rat, or elephant) are hearing them. Similarly, all sounds above 20 kHz are qualified as ultrasounds, but there are sounds for a cat or a dog (up to 40 kHz) or for a dolphin or a bat (up to 160 kHz). (Pujol, 2018)
• Age-related hearing loss, or presbycusis, is the slow loss of hearing that occurs as people get older. Tiny hair cells inside your inner ear help you hear. They pick up sound waves and change them into the nerve signals that the brain interprets as sound. Hearing loss occurs when the tiny hair cells are damaged or die. The hair cells DO NOT regrow, so most hearing loss caused by hair cell damage is permanent.
• There is no known single cause of age-related hearing loss. Most commonly, it is caused by changes in the inner ear that occur as you grow older. Your genes and loud noise (from rock concerts or music headphones) may play a large role.
• The following factors contribute to age-related hearing loss:
• Family history (age-related hearing loss tends to run in families)
• Repeated exposure to loud noises
• Smoking (smokers are more likely to have such hearing loss than nonsmokers)
• Certain medical conditions, such as diabetes
• Certain medicines, such as chemotherapy drugs for cancer. (Josef Shargorodsky, 2018)

• Why is it that younger people can hear high-pitched ringtones but older people cannot? How is this used to the advantage of younger people (e.g., when choosing cell phone ringtones)?
• The study revealed that when young adults are in a loud environment – such as a rock concert – their brains become less sensitive to relatively quiet sounds. This allows the listener to hear the relevant sounds (like a guitar riff) better without being distracted by irrelevant sounds. However, as a person ages, researchers found that older listeners become over-sensitive to sounds, hearing both quiet and loud sounds without the ability to ignore or tune out irrelevant auditory information. Without the ability to reduce sensitivity to irrelevant sounds, the individual experiences hearing challenges. “When the sound environment is loud, the brain activity in younger adults loses sensitivity to really quiet sounds because they’re not that important,” Herrmann said. “Whereas older individuals still stay sensitive to these relatively quiet sounds, even though they’re not important at the time.” “It’s a fundamental property of the auditory system to be able to adjust really fast to any environment a person goes into. If you cannot do that anymore, then in each situation your auditory system might be a little off. This means older individuals may be easily distracted and overwhelmed by sounds, or find them too loud,” Herrmann explained. (Marie-Élaine Lagrois, 2018)
• What happens to the human eye as a person gets older? Consider what happens to the ability to perceive images at different distances when the lens becomes more rigid. How might a person with myopia benefit from changes with time?

• How do the changes in smell and taste interact? Discuss the different types of taste. Are there any specific tastes that are relatively preserved with age? Do food preferences change with one’s ability to taste different things? How does this impact food choice?

References

Josef Shargorodsky, M. M. (2018, November 04). Age-related hearing loss. Retrieved from U.S. National Library of Medicine: https://medlineplus.gov/ency/article/001045.htm

Marie-Élaine Lagrois, I. P. (2018, Febuary 13). Neurophysiological and Behavioral Differences between Older and Younger Adults When Processing Violations of Tonal Structure in Music. Retrieved from Frontiers in Neuroscience : https://www.frontiersin.org/articles/10.3389/fnins…

Pujol, R. (2018, 06 06). HUMAN AUDITORY RANGE. Retrieved from JOURNEY INTO THE WORLD OF HEARING: http://www.cochlea.org/en/hear/human-auditory-rang…

Younger and older people respond differently to sound. (2019, June 04). Retrieved from Hear it: https://www.hear-it.org/younger-and-older-people-r…