However, they specialize in different combinations of tones. Some respond to pure tones, such as those produced by a flute, and some to complex sounds like those made by a violin. Some respond to long sounds and some to short, and some to sounds that rise or fall in frequency.
Other neurons might combine information from these specialist neurons to recognize a word or an instrument. Sound is processed in different regions of the auditory cortex on both sides of the brain. However, for most people, the left side is specialized for perceiving and producing speech. Damage to the left auditory cortex, such as from a stroke, can leave someone able to hear but unable to understand language. See how discoveries in the lab have improved human health.
Read More. For Educators Log in. Also In Hearing. Music: A Full Brain Workout. A typical day finds him reviewing results from experiments involving human brain imaging, particularly functional magnetic resonance imaging, or fMRI. This line of research has revealed that the human auditory cortex contains neurons that respond selectively to music -- not to speech or environmental sounds. This work has shown that sound processing in the auditory cortex happens in stages, beginning with the analysis of low-level features, such as loudness and pitch.
That processing proceeds step-by-step into higher-level features, such as the source of the sound production for example, whether the sounds are produced by speech and the identity of the person or thing producing the sound. McDermott's team has also developed an artificial neural network that can recognize sound and music. The network can identify words in speech and genres of music with the same accuracy as a human subject. Because the researchers can "look under the hood" of the software to see how it handles information at every stage of processing, they can compare each stage with the functions of the auditory cortex, as imaged with fMRI.
This comparison has shown that certain stages in auditory processing in the computer program are similar to those performed by the brain. Vibrations from the stapes push on the oval window, and set up pressure waves in the fluid-filled cochlea, the snail-shaped inner ear that contains the organ of Corti. In the organ of Corti, vibrations are finally transformed into electrical energy by cells known as hair cells stereocilia.
The tiny hair cells lining the cochlea are stimulated by different frequencies. For example, many people with hearing loss have high-frequency hearing loss, making it harder to hear high-pitched sounds.
This means the hair cells responsible for detecting high frequencies are damaged. While less common, some people have low-frequency hearing loss or mid-range hearing loss. These hair cells translate the vibrations from sound waves into electrical impulses that then travel along a complex pathway of nerve fibers to the brain.
Note: Hair cells play a vital role in your hearing. Blasting hair cells with noise is akin to trees in a hurricane, struggling to remain standing. Sound processing likely occurs in both the cochlea and the brain, Dr. But most of the neurological processing of sound occurs in the brain, he says. Brain cells, known as sensory neurons, transmit the sound information to various areas of the brain, including the thalamus, temporal lobe, and auditory cortex, the National Institutes of Health explains.
These are known as the auditory pathways. The auditory pathways process and decode sounds, turning them into something meaningful, like a question, a honking horn, or music. They also help distinguish between nearby, important sounds and less vital background sounds, as well as processing the direction and location of sounds. Many parts of hearing work directly in concert with the vestibular, or balance system, which is located nearby, within the semicircular canals of the inner ear.
How exactly your brain works when it comes to sound is still being explored by researchers. For example, tinnitus , or ringing in the ears, is still poorly understood, even as common as it is. Anything that obstructs the transmission of sound can lead to issues, Dr. Here, the types of hearing loss , and where the problem starts within the process:.
Hearing aids can be transformative for people with hearing loss. Fundamentally, they allow you to hear—but hearing aids are associated with other benefits as well, such as overall better health and improved quality of life, reduced loneliness, and even decreased risk of falls. To the extent that you can, protect your hearing, avoiding loud sounds and dealing with health-related problems that could affect your hearing in a timely manner.
Madeleine Burry is a Brooklyn-based freelance writer and editor. She's written about health for several online publications, including Women's Health, Prevention, Health, Livestrong and Good Housekeeping.
You can follow her on Twitter lovelanewest. Read more about Madeleine. Side Menu. Assistive listening devices Amplified phones Captioned phones Hearing aid compatible phones TV hearing aid and listening devices FM systems Alerting devices.
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