Presbycusis
Presbycusis is a condition affecting the hearing of many adults. There are a variety of causes, including damage to structures of the middle and inner ear. The result is loss of hearing—not complete deafness, but difficulty in detecting certain sounds within the normal range of hearing. Use each numbered item as a required subheading
Explain how normal hearing occurs. Include in your discussion the following points:
How is sound transmitted from the environment outside the body to the inner ear? What structures are involved, and how do they transmit sound?
What happens in the inner ear (cochlea) when sound waves are converted to neural signals? How is sound frequency (pitch) processed?
2. Next, summarize the causes of presbycusis and explain how they will interfere with the normal processing of sound as outlined above.
Discuss one source of presbycusis involving a problem with the outer/middle ear.
Discuss one source of presbycusis involving a problem with the inner ear
3. Finally, describe what it might be like to have presbycusis. Include the following points:
If you have normal hearing now, how would your ability to converse with others be affected?
What activities that you now enjoy would be limited by this condition?
How would such a condition affect your work life?
Include the sub headings of: “Introduction”, “How Normal Hearing Occurs”, “Causes of Presbycusis”, “Having Presbycusis”, and “Conclusions”.
Introductory paragraph ending in a clear thesis statement
Sample Solution
Hearing depends on a series of complex steps that change sound waves in the air into electrical signals. Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum. The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear. These bones are called the malleus, incus, and stapes. The bones in the middle ear amplify, or increase, the sound vibrations and send them to the cochlea, a snail-shaped structure filled with fluid, in the inner ear. The auditory nerve carries electrical signal to the brain, which turns it into a sound that we recognize and understand.
