Monday, August 6, 2018

What’s the real value of hearing aids?

“Well,” said the new hearing aid user as he drew a deep breath, “my hearing loss cost me three friendships that I know of, a strained relationship with my wife, two grandchildren who think I don’t understand them, boredom at church, and lost interest in attending get-togethers.” After a reflective pause, he added: “Sure I invested some money to get these hearing aids... but it doesn’t compare with what it cost before I got them!”

It’s true; hearing aids are not a low-cost investment.  But when you consider what hearing loss has or can cost you, the investment pales in comparison.  In this article I will cover the four main areas of life that untreated hearing loss can dramatically impact. 

Typically, the people you live with are also affected by untreated hearing loss. So it’s no surprise that patients and their spouses often report that even a mild hearing loss can put strain on a marriage.  When everyday conversation becomes a little difficult, the television becomes too loud and one person is asking for repetition, blaming the misunderstanding on the other’s mumbling, even the most loving couples will get frustrated.  The person with the loss doesn’t recognize the gradual changes in hearing and their spouse has had to alter their normal conversation style to compensate for the other’s hearing loss.  In most cases, today’s hearing technology and implementing some basic communication strategies will remedy daily life frustrations for both of you.

If family members are noticing that you’re having trouble hearing, it’s a good bet that your friends are too.  You may notice that you are straining to hear conversations on the golf course or playing bridge.  You may “fake it” by nodding when you really didn’t understand what was being said, or laugh at the punch line of a joke that you didn’t hear.  The authenticity of the relationship starts to shift.  A change in hearing seems to be a taboo subject for many people.  If a friend does mention something about your hearing, consider it’s true. If someone has the capacity to show this concern, they are a caring friend.  If misunderstandings from hearing deficits become the joke of the day, handle it with grace… you may laugh as well, but the true message is, your hearing is not keeping up with the rest of your life; it’s time to measure your hearing abilities.  

When you have a reduction in hearing, more effort is needed to follow conversations in background noise and at some point the amount of effort to understand becomes too taxing.  Without even knowing it, the change in your hearing will cause you to change your lifestyle as you start reconsidering dinner invitations, parties and other outings.  Going out to dinner, enjoying a party, sporting event, movie or interest group doesn’t seem like as much fun when you can’t follow conversation.  Often, I hear people say they don’t enjoy certain groups anymore, only to discover that it really is about their communication breakdown not a lack of interest in the group itself.  Untreated hearing loss leads to isolation, negativity, and depression. Ultimately, what makes life worth living are the relationships we have. 

We all know that your brain is what works your body parts.  So what works your brain?  One thing that stimulates your brain is the sound that is received through your ears.  If your hearing decreases, so does the stimulation to your brain.  Hearing typically decreases at such a gradual rate that you barely notice it, if you notice it at all.  The longer you wait to treat hearing loss, the more difficult it is for your brain to use the information it receives.  Recent studies show a correlation in cognitive decline and untreated hearing loss. Most people get their eyes and general health monitored annually.  When was the last time you had your hearing checked?  Get it done today…there is no substitute for healthy hearing. 

At Gilliom Audiology we offer complimentary hearing checks.  We encourage you to bring a loved one with you; it’s important that they are part of your diagnosis and treatment process.

So what are hearing aids really worth?  Your relationships?  Your health?  Your lifestyle?  It’s your decision.

Monday, July 2, 2018

Aging Before My Time


“It’s really making me age before my time.”

A short while back a new patient said: “It’s really making me age before my time”, and I thought about the images of “age” as he perceived.  His definition of age meant manifesting traits that made him seem older or breaking down. I understood – he was having a harder time keeping up with his life because of his hearing. 

Age is just a number.  It marks time. As an adult, your lifestyle doesn’t necessarily have to be defined by your age – if your health allows, at any age you can dance a jig or sit in solidarity. You can socialize with friends and family or you can be a loner in quiet. I have a five year old patient and I have a 104 year old patient.  The need to be connected to sound and life is just as important for both.  My job is to make sure that change in your hearing doesn’t change the way you live your life.

Many view hearing loss as a sign of aging and if they acknowledge the change they are acquiescing to a shortcoming. I wonder how many felt that way when they got their reading glasses or perhaps those people simply stopped reading.  Not likely.  More than 50% of those with hearing loss are under the age of 50.  When I was a young girl, I would have said 50 was old…but now at nearly 50, it’s just a number, and I am one of the 50% with hearing loss.  Just like me, this patient did not want changes in his hearing to lead to a decline in personal relationships, activities, and even cognitive processing.  Regardless of the number of years you have lived on earth, if you have a desire to stay connected, involved, independent and confident, you owe it to yourself to get your hearing evaluated and treat the changes in your hearing so that you can keep up with YOUR LIFE.

“There is a fountain of youth; it is your mind, your talents, the creativity you bring to your life and the lives of the people you love.  When you learn to tap the source, you will truly have defeated age.” – Sophia Loren.

For more information about hearing health and hearing aids in Jacksonville, FL visit our website at www.gilliomaudiology.com

Monday, June 4, 2018

The Sounds of Summer! Fun or Dangerous?


The Sounds of Summer!

As we immerse ourselves in summer fun and activities it's important to remember the things that keep us healthy and enjoy all of our summers to come.  We covered this topic on our facebook page (Visit us on facebook!) and posted our weekly Florida Time Union article on our practice website.  Here's the gist: there are so many things that we don't consider could damage our hearing.  It's our goal to provide you with the information you need to keep hearing healthy.  What is too loud?  How can I gauge a decibel level?  What can I do to protect my hearing?  We'll be happy to answer these questions for you!

Continued exposure to noise of 85 dB or louder, over time, will harm your hearing.  Noises above 90-95 dB can only be tolerated for a very short amount of time.  So what is 85 dB?  Let’s put this into perspective:  average conversation speech is between 55-65 dB, a washing machine or busy traffic is between 75-85 dB, while a hair dryer is about 95 dB and a chainsaw is between 100-115 dB.

Fret not!  You can protect your hearing AND enjoy the sounds of summer!  There are so many hearing protection devices available these days from disposable ear plugs to noise cancelling ear muffs and even custom fit ear molds for things like hunting and music.  Most of these don't completely mute all sound, they just bring the sound down to an acceptable decibel range. 

You can read this complete article as well as others on the editorials page of our website.

Blogs, Ads, Articles and more are written by the caring hearing staff at Gilliom Audiology, P.A. in Jacksonville and Jacksonville Beach, FL.  Providing doctoral level hearing care including: hearing test, hearing aids, hearing aid accessories, ear wax removal, and much more! 

Monday, April 2, 2018

Who? Where? Why? When?


A couple of years ago I went to a new optometrist to get a much needed prescription for progressive lenses.  I had been procrastinating - telling myself that it just wasn’t bad enough, and that I could still read “okay”. In all honesty, the first pair of progressive lenses was not successful.  The lenses were too small for an adequate field of vision.  So I waited for months to finally try again.  It made me think of many people who come to my office with the same thoughts about their hearing. I asked the optometrist a multitude of questions about his educational background, how long he thought my new lenses would work for me before I had to get new ones, how long it would take me to adjust to the progressive lenses, etc. He took his time with me explaining every step and educating me about the health of an eye and the natural progression of reduced focal length and need for more light. As a hearing care provider, I encounter similar questions about the ear and hearing. It is imperative that hearing care providers are educated and take time with you to answer your questions and concerns about your hearing loss, treatment options, and realistic expectations about your overall hearing. In the next few paragraphs, I will answer a couple of questions that are posed to me on a daily basis.



What is the difference between an audiologist and a hearing instrument specialist? In the State of Florida, all newly licensed audiologists (post 2008) must have graduated with a doctoral degree with a major emphasis in audiology and pass a demanding national competency examination. In addition to graduate school, audiologists must complete a residency or fellowship year as part of their training. In comparison, a hearing instrument specialist must complete a minimum six month hearing aid specialist training program, have a high school diploma or equivalent, and pass the International Licensing Examination.

Audiologists in Florida will hold a masters degree in the science of hearing or a doctoral level degree. An Audiologist is a professional who specializes in evaluating and treating people with hearing loss. Audiologists have special training in the prevention, identification, assessment, and non-medical treatment of hearing disorders. By virtue of their graduate education, professional certification, licensure, and training, audiologists are the most qualified professionals to perform hearing tests, dispense and fit hearing devices and refer patients for medical treatment or evaluation. 



How will I know when it is time? If you are like me with my glasses, I figured it was just natural to start having more problems reading the fine print I would just get by for a while longer. I stopped by the drug store to buy “readers” but with my current vision problem, the “readers” just magnified my blurry vision. So I stopped reading books at night because it was just too difficult and my eyes would tire. Ironically, I had changed my lifestyle because I didn’t want to “change.” I find that individuals with hearing reduction have also begun to change their lifestyle so that they don’t have to “change.” Unlike vision, your hearing affects everyone around you. In fact, because your hearing changes gradually, you are usually the last to “figure out” you really do need enhancement for your hearing. You don’t realize that you have begun to compensate by turning the television louder, relying on your spouse to clarify the restaurant specials, changing your entertainment preferences to ones that have less background noise, etc. You may have developed compensatory skills that have been finely tuned such as tuning one person in and the other one out, repeating what you think you heard to confirm its accuracy, making educated guesses, etc. These are all excellent skills to acquire, but they will not solve all your hearing problems. Like it or not, we all change. On average, our hearing begins to noticeably change in our 60’s.  Some people have a head start to this natural change from noise exposure like recreational firearms, work environment, or genetics.  Even health issues like diabetes and vascular disease accelerates hearing changes.  It is really simple. If you or someone in your family suspects that you aren’t hearing as well as you used to, get your hearing tested. 

As I write this, I know that my new lenses are keeping me in the game. Now, I experience change as an integral part of maturation; not a threat to who I am, or an acquiescence to self-perceived shortcomings. Change is a constant and the time is always NOW. If you are making changes to compensate for a reduction in your hearing, subtle or grand, the time is now. You monitor your vision, your blood pressure, your physical health with no second thoughts …now is the time to start monitoring your hearing.  Don’t miss out on the sounds of your life.

~ Dr. Nancy Gilliom, Ph. D.

Monday, March 5, 2018

Prolonged Exposure to Loud Noises





Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf




Noise-Induced Hearing Loss Alters Brain Responses to Speech


DECIBEL DIAGRAM b
Image courtesy UT Dallas: Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders.
Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds.
Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD).
Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.
Dr. Michael Kilgard
Michael Kilgard, PhD
“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”
To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.
Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.
In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.
In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.
“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”
The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.
The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
http://www.hearingreview.com/2013/12/researchers-find-significant-improvement-for-tinnitus-sufferers-with-vns/
http://www.hearingreview.com/2011/01/nih-research-rebooting-the-brain-to-stop-tinnitus/
Source: UT Dallas
- See more at: http://www.hearingreview.com/2014/08/noise-induced-hearing-loss-alters-brain-responses-speech/#sthash.pUUSNSG1.dpuf
DECIBEL DIAGRAM b
Noise-Induced Hearing Loss Alters Brain Responses to Speech
Published on August 4, 2014

Dr. Michael KilgardImage courtesy UT Dallas:

Regular exposure to sounds greater than 100 decibels for more than a minute at a time may lead to permanent hearing loss, according to the National Institute of Deafness and Other Communication Disorders. Prolonged exposure to loud noise alters how the brain processes speech, potentially increasing the difficulty in distinguishing speech sounds, according to neuroscientists at The University of Texas at Dallas (UT Dallas). In a paper published in Ear and Hearing, researchers demonstrated for the first time how noise-induced hearing loss affects the brain’s recognition of speech sounds. Noise-induced hearing loss (NIHL) reaches all corners of the population, affecting an estimated 15% of Americans between the ages of 20 and 69, according to the National Institute of Deafness and Other Communication Disorders (NIDCD). Exposure to intensely loud sounds leads to permanent damage of the hair cells, which act as sound receivers in the ear. Once damaged, the hair cells do not grow back, leading to NIHL.


“As we have made machines and electronic devices more powerful, the potential to cause permanent damage has grown tremendously,” says Michael Kilgard, PhD, co-author. “Even the smaller MP3 players can reach volume levels that are highly damaging to the ear in a matter of minutes.”

To simulate two types of noise trauma that clinical populations face, UT Dallas scientists exposed rats to moderate or intense levels of noise for an hour. One group heard a high-frequency noise at 115 dB, inducing moderate hearing loss. A second group heard a low-frequency noise at 124 dB causing severe hearing loss. For comparison, the American Speech-Language-Hearing Association (ASHA) lists the maximum output of an MP3 player or the sound of a chain saw at about 110 dB and the siren on an emergency vehicle at 120 dB. Regular exposure to sounds greater than 100 dB for more than a minute at a time may lead to permanent hearing loss, according to the NIDCD.

Researchers observed how the two types of hearing loss affected speech sound processing in the rats by recording the neuronal response in the auditory cortex a month after the noise exposure. The auditory cortex, one of the main areas that processes sounds in the brain, is organized on a scale, like a piano. Neurons at one end of the cortex respond to low-frequency sounds, while other neurons at the opposite end react to higher frequencies.

In the group with severe hearing loss, less than one-third of the tested auditory cortex sites that normally respond to sound reacted to stimulation. In the sites that did respond, there were unusual patterns of activity. The neurons reacted slower, the sounds had to be louder, and the neurons responded to frequency ranges narrower than normal. Additionally, the rats could not tell the speech sounds apart in a behavioral task they could successfully complete before the hearing loss.

In the group with moderate hearing loss, the area of the cortex responding to sounds didn’t change, but the neurons’ reaction did. A larger area of the auditory cortex responded to low-frequency sounds. Neurons reacting to high frequencies needed more intense sound stimulation and responded slower than those in normal hearing animals. Despite these changes, the rats were still able to discriminate the speech sounds in a behavioral task.

“Although the ear is critical to hearing, it is just the first step of many processing stages needed to hold a conversation,” Kilgard says. “We are beginning to understand how hearing damage alters the brain and makes it hard to process speech, especially in noisy environments.”

The work was funded through a grant from NIDCD. Other UT Dallas researchers involved in the study were co-author Margaret Fonde Jonsson, PhD, Amanda Reed, PhD, Tracy Centanni, PhD, Michael Borland, Chanel Matney, and Crystal Engineer, PhD.


The Hearing Review featured Dr Kilgard’s earlier work (along with other colleagues at UT Dallas, including Drs James & Susan Jerger, Ross Roeser, Emily Tobey, Aage Moller, Linda Thibodeua, George Gerkin, Jackie Clark, and Anu Sharma) in an October 2002 article. Other HR articles related to  research by Dr Kilgard can be accessed at:
Source: UT Dallas