Question

Which of the following is true of rate coding along the basilar membrane?

1) Rate coding occurs for frequencies greater than 500 Hz.
2) The basal end of the basilar membrane shows the greatest movement to a frequency of less than 200 Hz.
3) Lower frequencies are coded by rate of firing that is cued to the movement of the apical end of the basilar membrane.
4) Cochlear implants can be used to signal frequencies up to 20,000 Hz.
5) Rate coding is due to volleys of neurons that fire in sequence.

Answer 1

Different regions on the basilar membrane respond to different frequencies of sound waves. Lower frequencies are coded by the rate of firing of hair cells at the apical end of the basilar membrane. Cochlear implants can signal frequencies up to 20,000 Hz.

Step-by-step explanation:

The hair cells on the basilar membrane are sensitive to different frequencies of sound waves. The basal end of the basilar membrane responds best to high frequencies, while the apical end responds best to low frequencies. Therefore, lower frequencies are coded by the rate of firing of hair cells that are cued to the movement of the apical end of the basilar membrane.

Cochlear implants can be used to signal frequencies up to 20,000 Hz, which is the range of sound that human ears can detect. However, rate coding along the basilar membrane is not due to volleys of neurons firing in sequence, but rather the specific activation of different hair cells along the membrane as a result of the frequency of the sound waves.