Chapter 1. Hearing: From Vibration to Sound

Short Description

Hearing is an important aspect of communication and survival in animals and humans.

Long Description

The human auditory system contains highly evolved, complex mechanisms that allow us to detect and interpret information that is carried through sound waves. In this program, students learn about the various components of the auditory system, how hearing works, and what causes hearing loss.

David Myers explains that sound waves are simply the jostling of molecules making contact. He uses the analogy of people bumping into one another while moving through a stadium tunnel to describe this process. These sound waves enter the ear, initiating a motion that then vibrates the cochlea and sends impulses to the brain.

The process of these impulses reaching the brain begins when hair cells in the cochlea are electrically charged, causing an impulse that fires a neuron to the brain. Barbara Shinn-Cunningham adds that vibrations in the air are actually linked to vibrations of the hair cells, influencing the tone and frequency of the sound we hear. Two streams of auditory processing occur in the auditory cortex, which tells our brain what to do with the impulse coming in.

Our auditory system is fragile and can be easily damaged. Hearing loss caused by heredity, illness, or injury is the result of cell death and is irreversible.

Questions