Marshall Chasin

Marshall Chasin, AuD, is an audiologist and the Director of Auditory Research at the Musicians’ Clinics of Canada, Adjunct Professor at the University of Toronto (in Linguistics), Associate Professor in the School of Communication Disorders and Sciences at the Western University. He is the author of over 200 articles and 7 books including Musicians and the Prevention of Hearing Loss. Dr. Chasin has been the recipient of many awards over the years including the 2012 Queen Elizabeth II Silver Jubilee Award for service to Canada and the Canada 150 Medal in 2017. He has developed a new TTS app called Temporary Hearing Loss Test app.

Featured image for “Noise Cancellation Earphones and a Neat AuD Capstone Project”

Noise Cancellation Earphones and a Neat AuD Capstone Project

Marshall Chasin

I recall sitting in my very first audiology class in 1979 (when tuning forks had just been invented and all hard of hearing people were using wither body worn hearing aids or large tin horns in their ears) and the instructor was trying to explain the difference in calibration between using earphones (minimal audible pressure) and loudspeakers (minimal audible field)

Featured image for “And the Winner Is ….(Part 3)”

And the Winner Is ….(Part 3)

Marshall Chasin

If you have been reading earlier parts of this blog series, I had only promised to write a 2-parter. Well, here is part 3! The reason for this rogue insertion of yet another installment to this series is the number of emails that I have received about how hearing protection can actually be assessed using real ear measurement – hence,

Featured image for “And the winner is….(Part 2)”

And the winner is….(Part 2)

Marshall Chasin

In part 1 of this blog series, I had talked about a patient who had a relatively rare 3000 Hz noise (music) induced hearing loss notch and not the more common one at 4000 Hz or 6000 Hz. The ear canal resonance was at 2000 Hz as compared as opposed to the more common “average” of around 2700 Hz. The lower frequency

Featured image for “And The Winner Is….(Part 1)”

And The Winner Is….(Part 1)

Marshall Chasin

Whenever I fit hearing protection such as Musicians’ Earplugs, I verify the function using real ear measurement. Of course, in the design of Musicians’ Earplugs there is a correct assumption that the acoustic gain that is generated will offset the insertion loss caused by the occluding earmold. That is, if people have a 2700 Hz resonance due their outer ear,

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Emotion, Speech, and Music

Marshall Chasin

Rachel Hottle is the guest contributor to this week’s blog at HearTheMusic. Rachel is a fourth-year undergraduate at Swarthmore College in Philadelphia, Pennsylvania, where she is studying music and biology. This summer she is volunteering as a research assistant in the SMARTlab (Science of Music, Auditory Research, and Technology) at Ryerson University. She hopes to pursue graduate study in the

Glutamate, Adenosine, and our critical period of learning – part 3

Marshall Chasin

We are a bag of bio-chemicals mixed in with a lot of water and some other tissues and bone that give us structure. My waste-line may be a slim 34” at sea level, but over 35” at the top of Aspen Mountain- we are held together by atmospheric pressure, bones and other tissues- but what makes us go round are

Featured image for “Glutamate and Stress – Part 2”

Glutamate and Stress – Part 2

Marshall Chasin

I recall reading an article from 1983 in a then, new journal of the American Auditory Society, called Ear and Hearing. I remember showing it to my colleagues and commenting how silly it was and that they would publish anything, just to get an article to fill the pages of Ear and Hearing. Well, I was wrong! Ear and Hearing

Featured image for “Glutamate and How We Hear – Part 1”

Glutamate and How We Hear – Part 1

Marshall Chasin

Glutamate is the main neurotransmitter substance in the cochlea and auditory system that make it work. Neurotransmitter substances are the chemicals that live their lives in between neurons in the synapse that allow neurological impulses- inhibitory (IPSPs) and excitatory (EPSPs)- to proceed (and feedback) along the neural chain up to the appropriate center(s) of the brain. Names such as Dopamine and Serotonin

Impulse noise and music exposure

Marshall Chasin

Dr. Richard Price has probably done more than any one researcher to delineate the potentially damaging aspects of impulse noise on our auditory system. He did most of his work in the 1980s and 1990s at the U.S. Army Research Laboratory, but had continued to publish well after his military incarnation. Of course the military is concerned about minimizing the

Featured image for “Speech is not music… and music is not speech.”

Speech is not music… and music is not speech.

Marshall Chasin

I am always surprised by how the various hearing aid manufacturers lump the two words “speech” and “music” together in one sentence…. “Hearing aid X can help with speech and music, and can help you jump higher and run faster….”. Of course everyone knows that the last part is true and many of my hard of hearing clients can leap