The Giants of Audiology: Interview with Marshall Chasin, AuD

Welcome to this Week in hearing in our special series titled Giants in Audiology. Hello, I’m Bob Traynor, your host for this episode. Today. My guest is Dr. Marshall Chasin, a Canadian audiologist from Toronto, Canada, who has become the Canadian Musician’s Audiologist. And he tells me that he has a black belt in karate and kung fu and plays several instruments, including the clarinet, the guitar and actually the radio as well. Thanks so much for being with us today, Marshall. Well it’s my pleasure, Bob. So, before we begin, let me read Dr. Chasin’s. Dr. Marshall Chasin, head of Audiology at Musicians Clinics of Canada, and is an adjunct professor at the University of Toronto and Western University in Ontario, Canada. Dr. Chasin holds a Bachelor of Science degree in mathematics and linguistics from the University of Toronto and a Master of science degree in audiology and speech sciences from the University of British Columbia. He further has the AuD from the University of Arizona Health Sciences Center. He’s the author of 200 articles and eight books, including Music and Hearing aids, that is out through Plural Publishing in San Diego. he’s a featured columnist in Hearing Review. His column is titled Back to Basics and also the developer of an. Interesting app for iPhones and so on, that he’ll hopefully tell us a little bit about called Temporary Hearing Loss Test. Dr. Chasin has received numerous awards, including, if I pronounced this correctly, Marshall. The 1991 Eve Kassirier Award for Speech and Audiology Canada. The 2004 Professional Leadership Award from the Audiology Foundation of America, 2009 President’s Award from the Canadian. Academy of Audiology and something that sounds pretty important to me. The 2012 Queen Elizabeth II Silver Jubilee Award. Also the 2013 Jos Millar Award for the British Society of Audiology and the 2017 Canada 150 Medal. Thanks again so much for being with us here today, Marshall. And I think where we want to start with this whole thing is, where did this all begin? We all have those important things that happen to us when we’re like, even little kids and so on. So maybe you could tell us a little bit about where the beginnings were and a little bit about how some of these things began to develop up. Well, I started, unlike most people in this field, not having heard anything about audiology. I was in grad school. I still had not heard of audiology. I didn’t know what they did or even what the word meant. I thought they worked in stereo shops. I had no sense of audiology. But when I was growing up, I, like a lot of kids, didn’t particularly do well or like school in the earlier years. I couldn’t read and write until I was three or four. I was very delayed in that respect. I was the youngest in the family. That tends to happen, especially if you born near the end of the year, where everyone else in the class is up to a year, almost a year older than you are. But I did excel at mathematics, and I recall one or two or one of the earlier years being told that I scored in the top several students in the school board in mathematics and mathematical reasoning. Of course, that sense, it doesn’t really happen or arithmetic. And I guess that continued on for a little while. I gradually did better years later on. I a little bit more mature as a student, I guess, but I always was more biased towards the sciences rather than the arts. Actually, that may have been a little bit, because what dad, I think, was an engineering physicist and then then maybe some of the art sayings came from mom with her continuous quoting of Shakespeare, as we talked about in the past. So that is true. My mother. Didn’t have any formal education beyond high school at that time. It wasn’t thought that girls would go to school, at least her family, which is unfortunate, but she would quote Lady Macbeth even from a very early age. She just loved Shakespeare and loved some of the poetry and the prose from the previous century. So I was inundated with that from a very early age. My father, of course, was a scientist. He was an engineering physicist. And after World War II, he started working in various locations. And actually, in the 1960s, he decided that he had enough of engineering physics, and he retired as the vice president of a large financial organization. Using the same techniques and same technologies as a physicist only apply to the economic field. Cool. I guess then, because of that. orientation. You were kind of a very young mathematical wizard. I don’t know if I was a wizard, but certainly math came very easy to me, and I always enjoyed math. Actually, I kind of joked that when I was very young, my mother would tell me bedtime stories of acoustics. In fact, I wrote a little bit about that. If you go to my website, www.musiciansclinics.com, then go over to publications and scroll all the way down to the bottom. We have five or six humorous articles. One of them is about the bedtime stories my mother used to tell me when I was very young about earmold acoustics and hearing aid acoustics. Now, oh it wasn’t really I could have made that up, but it could have happened. Yeah. But also high school found you as a pretty good swimmer as well, from what I understand. I did take up swimming. Very early. I teach so well, so that was pretty easy. I became a lifeguard in my high school time and later a swimming instructor, and I actually carried that on all the way through undergraduate university. And I think the last time I taught swimming was my final year of undergraduate, so that’s always been a nice summer job, part time job, off to the side. I know it sounds very I apologize, but I was the president, the typical president of the chess clubs, and I did very well. I had a fairly good rating in the Canadian Chess Federation at that time, certainly not at Mastery’s level, but it was quite high. Well, that kind of goes along with the mathematics, I think, Marshall, because chess is a very complex, strategic kind of a game and many of us would like to be at least reasonable at chess, because now, we might not have thought it was so cool in high school, because. We all wanted to be the quarterback on the high school football team. However, these days that’s quite a fabulous skill for strategic implementation. So you decided to take up some karate, I think, as a teenager as well. Well, not as a teenager, actually, karate I never took up until I was in my mid 40s. And I was the chauffeur for my son who wanted to take up karate. He was eleven or twelve at the time. And I would sitting in the waiting room while he was having karate lessons, I would peek in there, I could do that. And so I started to train about three or four months after he had started. And our sensei that’s the karate instructor was always very careful about not pairing us together and occasionally during sparring sessions here together. And I’m still nursing a broken rib on my left hand side because of a wonderful pic by son gave. But usually we weren’t here together when he. At university age, he actually took off and he didn’t know other trains in karate, but I’ve continued it since my early 40s, so I’ve been a black belt in the last 15-20 years. Karate and kung fu, a little bit of judo and some weapon work as well. Well, I hope that we’ll only end up being in situations where we have academic fights rather than other kind of things. So that was learning to all our colleagues out there, don’t mess around with Marshall because he knows the Marshall-Arts. Very good. Thank you. As if I’d never heard that joke before. Oh, I bet you have. All the time. I’m only authorized to beat up five year old kids because the seven year olds, they come after you, so I’m not that good. So also about that time, you picked up the guitar as well. Yeah, in high school, I picked up the guitar. It’s one of those instruments you could teach yourself. And I remember. Down one day and learning the twelve chords that are necessary to learn how to play the guitar. And you can do a lot with even three or four chords, seven by twelve. And so I started to play the guitar. Of course, in junior high school high school I was in the band playing the clarinet and they are different instruments, of course they have major differences between them. Clarinet is not the coolest thing to play at a party whereas Car kind of is more cool to play at a party. You could also sing along with guitar and you can’t sing along with a clarinet. I thought it was pretty good as a clarinet player but whenever the opportunity arose my music teacher would always shove me one clarinet section back. So second clarinet, third clarinet I think Beethoven has something called the Egmont Overture three piece. It has four clarinet part. And guess who got to play 4th clarinet? I think the fifth clarinet they are in. Hallway in the cloak closet with washing down the hall. So I guess the writing was on the wall that I wouldn’t be the best clarinet player, but I enjoy it, and actually, I play it to the state. I’d rather pick up my clarinet than my guitar. And probably a little bit of Benny Goodman and some of those other things going along with that clarinet playing. I’m sure not as good as Benny Goodman. but I already saw these great lineup players. 1940s and 30s were wonderful. Maybe about 1/10th their skill level. Well, so that’ll be a good thing for some party sometime to see how well, we put out a record with Benny and we listened to Marshall play at Clarinet, but I understand, too, like, in high school, your mathematics skills were pretty amplified as well. Yeah, I was the typical nerd who went into all the math contests and tried to solve these. Unusual problems that we used to have. I remember there was a time where I solved an unsolvable conjuncture. Of course, I was very naive, and I thought I had solved it. And I did solve part of it. I remember my math teacher being quite impressed. But when I got to university and took real math, I realized that I’d already solved the easy part and only a small fraction of it, but it was start, and it kind of gave me the positive reinforcement to continue on with math. Math is not the type of field we go into lightly. We have to really kind of be dedicated to it in order to do those constant math problems. Some of the concepts in math are a little bit abstract, I think is a better way of saying it than anything else. But I enjoy it. Was a wonderful way of spending high school. I wasn’t a complete nerd in high school. Well, I was, but not a complete nerd. I was on the swim team as well. Breaststroke and. Front freestyle, which is front brawl. I didn’t do very well, but again, I was cool enough to be on this one team. Oh, from there you moved on to the University of Toronto for your undergraduate studies? Yeah, I think it was a given that I would go to the University of Toronto. My father had gone there, one of my sisters had gone there. It was just assumed that I would go there. And they did have a very strong mathematics department at that time. Unfortunately, it was the mid 70s where most of the professors english was not their first or second or sometimes third language. And so most of my professors spoke German. Some were from Switzerland. And I remember, for some strange reason, always doing better in those courses where we had Swiss German professors. Something about their language, their speech, I just loved listening to it. You’d walk in and you say, we will now study. these equations enjoyed, and there’s just something musical about his voice, and you just listen so intently. And so a lot of the courses that could be difficult otherwise. I had some wonderful teachers, at least in some courses. And let’s see. And you even ended up with a mathematics and linguistics orientation at Toronto. So kind of a combination of both of those things. Nowadays, my background probably would be called cognitive sciences linguistics, but back then, it was just called mathematics and linguistics. So I did take a fair number of linguistics courses in my undergraduate. My preference is and always has been phonetics and a bit of phonology, but mostly phonetics. I’m a great lover of the movie my fair lady, based on shaw’s book pygmalion, and I view myself a little bit. Professor Higgins. Not that I try to teach Eliza Doolittle how to speak better for class of her society but I liked the rhythm of language and the rhythm of speech and in fact, in mathematics most of my orientation was towards algebra formal algebra. Now, in mathematics we call the normal algebras. A linguist might call them a syntax and interestingly enough, even though that was my interest I took my fair share of syntax courses. But I think my passion was always speech patterns or phonetics or sound patterns. And when it came to graduate after four years, I had three options I could go into teachers college and become a high school math teacher but it was the late seventy s and nobody’s hiring math teachers. But I could have seen myself as a math teacher with my career. I could have gone into my master’s of Mathematics and. I received a full scholarship into mathematics. But at that time, all the great math problems were being solved by non mathematicians. So there’s something called the four color conjecture. It’s really easy to prove three color conjecture. It’s trivial to do the five color conjecture, but the four color conjecture and you have a map with four adjacent colors that are not the same, that are not the same color side by side does not prove it. Now, this is actually a very important conjecture in practicality when we schedule. So, for example, I have to take an exam on Tuesday. Well, I can take the exam on Tuesday because I’m taking this course, which is an exclusion of another course that I was not allowed to take. And so maybe they’ll put that other course at the same time. So this way the schedule would mean that you wouldn’t have two courses at the same time. By that time, in the late seventy s, all the big math problems such as the four color conjecture were being solved by the upstarts from down the hall, in the computer science department, and it wasn’t very elegant. They did it and they proved it, but it wasn’t very elegant. So I saw the writing of the wall. So my third option was to do my master’s of linguistics, which I did choose to do. I was intending to look at formal algebras, formal syntaxes. But then very quickly I realized that my passion was more acoustic phonetics than anything else. In fact, when I went to linguistics department, I wrote quite a few computer science programs. We used to call it programming. Now, I know they call it coding, but in the day we used to call it programming. And I wrote a text editor to parse a language, do a syntactic analysis. My thesis was actually a simulation. I wrote of the vocal cavity and the nasal track. And I was able to develop a numerical analysis of the vocal tract. So I was able to change the dimensions and the parameters into. At certain outputs and how they would differ. That actually became part of my master’s thesis when I did linguistics. And I also understand in Canada, you guys have some interesting kinds of requirements for degrees, and there was a French requirement that was required for the master’s program, too, right? Indeed. And that is the case in linguistics to the state. But certainly in the knew that my future as a PhD. Would be impossible because I did not know two other languages other than english, and that was a requirement. The linguistics department had accepted mathematics as one of my languages, which was very nice. But although my reading French isn’t too bad, my speaking and writing french not the best. Well, it’s actually very poor. And I tried to pass the french language requirement. I didn’t, and I knew there. The writing was on the wall. So I started to look elsewhere, knowing that my advanced degree in linguistics at that time in Canada would have been problematic. My Latin wasn’t too bad, actually, and I could have used that. But I don’t think Latin was acceptable as a modern conversational form of Latin at that time. Actually. Most of my Latin is self taught, but my writing reading of Latin wasn’t too bad, actually. So I guess I could have found that. But I was looking around, and my graduate advice said, had you ever heard of audiology? And I said, I don’t want to look in the stereo shop. I just didn’t know when audiologists was. Well, I have to tell you, that used to be here. When someone would ask me, what do you do? I would say, I’m an audiologist. And they would say, well, what kind of stereos do you sell? Because so that was kind of a common thread that went thread what an audiologist was. Early on, I would say. In the 70s, we maybe had 30 or maybe 40 audiologists in my entire country, with the majority of them being American trained. We did have several Canadian three or four, actually Canadian programs, but we never had an undergraduate in communication disorders. So I never had the opportunity to take any speech language pathology or audiology courses in the undergraduate other than the linguistics courses, reception courses I normally took, and courses that I guess would be called speech language pathology, such as language acquisition, but we never encased it into an undergraduate communication disorders program. So when I was in graduate school, one of my graduate classes suggested audiology. I looked into it, and actually it looked really interesting. It was a nice combination between the arts and the sciences. It was a people field, so I knew I would be sitting in front of a computer screening the rest of my life like I would be, let’s say, in. Math, mathematics. And so I applied to actually several programs I do in the States. And they trimmed me down. I had a straight date. I don’t know why they trimmed me down to this day. And I usually razz them. So I have to ask Goldstein that I did along the line. He’s no longer with us. Oh, I know. But I did mention to him and beet some over beers one day, and it was very positive statement. But they did accept me at the University of British Columbia on the other end of the country, in the west side of the country. And for the first time I saw mountains and ocean, something I’d actually never seen before. Toronto is a relatively flat environment. We do have certain hills, but the hills are 30 or 40ft tall. One of the things that I think develops many of us in many areas is that some of us don’t come from traditional speech and hearing programs. We bring some of the skills that we obtain. From other areas, impose those into the communication disorders, speech and audiology kinds of areas. What happens is that you take a lot of those things and present them into the profession, which gives the unique perspective and some of the things that you’ve written about over the last number of years. But I understand that while you were at the University of British Columbia, you used to kind of play the guitar in the park and things like that to make a couple of bucks as all of us have to do during graduate school, doing something. Well, it is true funding is not high priority program that I was in, but I had saved up, of course, and my parents helped me a bit. I did have to play guitar in. Stanley park, which is their big park there. I wasn’t very good, but you only need to know two or three songs for people move on, and if you stuck around, you started to tell them math jokes, and they moved along rather quickly, so it was an easy thing to do. I also tutor a lot of undergraduate statistics, a lot of accounting students. Interestingly, my name got around for accounting students. I tutored them in statistics so they could pass their requirement of statistics. So I was able to play around outside of audiology. Audiology was kind of interesting. The University of British Columbia program back then was a little bit unusual. It wasn’t clinical, it wasn’t research. It was theoretical. And actually, I kind of liked that. And that’s one of the reasons I chose it. So I didn’t really get to push anybody an audiometer until well into my second year, which had to do some placements. And giving the background as a theoretical background. The framework before I even got to read about the research I think was very important. Also many of the classmates came from different fields. I went to school with someone that came from chemistry. There was someone from Old English well, she didn’t survive but that’s not because her background in Old English but it was a very varied background. Getting back to your question. In fact, to this day if you look at some of the people in our field that have really been a lot such Mead Killion for example, Mead also went through mathematics and he only discovered audiology in the late seventy s and with Laura Bilber at Northwestern University and prior to that he was mathematician Eddie Belcher who invented multi Bank compression that we use today is a lot Bill Cole who Is one of the fathers of real ear measurements and engineering, brings his knowledge base to our field. In fact, Mead Killion was the inventor of the insert earphones that are now the field. He was responsible for much of the miniaturizations that made hearing aids smaller, and again, that came from outside of our field, as well as some concepts in hearing aid fitting, too, and understand that Mead, as well as Robyn Cox were kind of in addition to your mentors at British Columbia. They were some pretty strong mentors for you in the development of some of the things that you have come to present to the field at this point. Well, First University of British Columbia, actually, I have many mentors per se. They tolerated me somewhere, afraid of me. But regardless, I did get three. And I think I did thank them for the wonderful overview education that I received there. But when I was there, there was an article that came out a monograph. It came out in 1979 by Robyn Cox. I’d never heard of Robyn Cox before. And it was a wonderful monograph about ear mold acoustics. And it occurred to me when reading it that the computer simulations that I was doing my graduate of linguistics of a particular human vocal tract were using the same laws of physics as the ear mold acoustics or room acoustics or even musical instruments. And so I read and reread and read again. That 1979 autograph. It’s not very long. It’s only about 30 or 40 pages. But I got in contact with Robyn Cox, who’s at that point in University of Memphis this and we opened up a dialogue. This is before the Internet, so this was by letter. I know that’s the old fashioned way of doing it. By letter education. I would send out some computer cards to her. We used to do all our programming on computer cards back then, and I would send her stuff down. She would look at it, not really understand what I was getting at some point, but she was always very supportive and very nice. Also in 1979, something else happened. Mead Killion published the first part of his thesis. Actually, it was in his thesis, but I actually didn’t publish until ’81, when I graduated, about to graduate, and I think it was in the journal of speech and hearing research. And when Mead Killion did his PhD in audiology. He did it in two parts. One was the electrical part, one was the acoustical part. Well, the acoustical part was published in 1981, just as I was graduating. And he essentially did developed a whole series of ear molds. And we expanded the field of ear mold acoustics dramatically at time. And we had bell molds with filters in them with means. 8CR, which stands for a band without 8000 resonance, 8000 Hz. So the mold itself would give you a flat or etymotic response. That was very interesting at that point, but I did notice he made a mistake in his calculations and I wrote off a little letter to and showed him as a snot nose kid just graduating. He made a little mistake and he said no, I didn’t make a mistake, but we don’t want to have exactly a 3000 Hz resonance. We want to have a little bit off and these are other reasons. He was of course talking about something called … but I didn’t know what that was at that time. But he was always very positive with me, very supportive to this day. I wrote a book very recently last year called Music and Hearing aids. And Mead was nice enough to direct forward of that book. So he’s always been very good about kind of helping me get back on track. I veered off track or helped to publicize things when I was on track on those few patients. I’m sure Mead appreciated the fact that you had much more of an orientation toward mathematics than the rest of us would have had. That most audiologists don’t have quite that mathematical orientation. And Mead has always been to all of us, I think, very tolerant of our weaknesses in some areas. That is a strength for you, where you guys could have actual intellectual conversations and the rest of us would say, oh, that sounds really neat, that sounds really interesting. And not having half of a clue of what the background was, only actually what the result might have been. But after your experience at the. British Columbia. You took a position at the Canadian Hearing Society. It was an opportunity to go back home, visit my parents, my family 3000 miles away. I think we think in terms of kilometers, so I had to convert miles. Just that. That’s why I stepped into a little bit there. But, yeah, I got a job at Canadian Hearing Society. It was an excellent first job. I had a wonderful boss, Tanny Nixon, who allowed me the flexibility to do really what I wanted to do. On one hand, I had to learn the ropes. I think anybody can move out of school. It’s a good idea to work with someone else for a period of time to learn the ropes, to see how things are really done, to see some of the subtle things that come up. And then after several years, or four or five years you could be being, in your own mind at least as a master audiologist where you can go up in your own and hopefully allow your patients to get the best services and most reasonable. Services. The Canadian Hair Society is more of a rehabilitative place rather than medical place. But of course, we did work closely with physicians of that time, so I did learn a lot of the ropes. I also learned a lot of stuff I had never thought about before. So, for example, Canadian Hearing Society was always advocating for service. They weren’t necessarily in favor or means any particular point of view. And I remember one of my professors at the University of British Columbia said, well, we’re going to talk about sign language, manual communication, total communication, oral communication, oral, spelled both ways oral and A-U-R-A-L. And by the time you graduate, you’ll have a prep. Well, by the time I graduated, I didn’t have a prep. I just didn’t really know. I could see advantages of all different ways. And when I hit the Canadian Hearing Society at that time, there was a lot of stress with sign language and total communication, and I kept. seeing a lot of Deaf people, capital D- Deaf who are culturally Deaf. I took quite a bit of sign language as well. But also the reason why the Canadian Hearing was so pro total communication and sign language was not that they were necessarily pro that, but there were just not enough services for that. And so it was important to them to provide services to the community. And it was a very interesting place. In my last two years at the Canadian Hearing Society, I was on a federal grant on health promotion where my main role was to go around to whoever would listen to me, schools, tertiary nursing units, nursing homes, other residential care facilities, and just talk. hearing and hearing loss prevention. And so I did get a lot of experience talking to groups and finding out what works and what doesn’t work you can’t use. Big giant words that people aren’t not familiar with the jargon. And I’ve actually I actually use that in my terminology today. Certain words I would never use are words on obviate. You know, they look at you and say, what does that mean? So it was a great opportunity at the Canadian Hearing Society. And in 1985 I met I went out, my oldest was born, CJ, and I wanted to spend more time with her, which I did, and it was a very good year. I was finding that I could work really about one or two days a week total and make as much as I did at the haering society as full time as a salary. So I never ahd a lot of chance to spend with my daughter. And then a year later I was getting a little bored, I must admit, and she would get a little bit more independent. And I ran into this gentleman named John Chong, another mentor of mine. John is a very interesting gentleman. He’s. Electrical engineer got tired of that when into medicine. Medicine john, at age 13 or 14, was already a concert pianist and had already reached the highest levels of piano training in Canada. We’d call it the associate degree ARCP. And he did come down, unfortunately, with carpal tunnel syndrome. So he no longer play like Chopin. And so he had to go across the hall to the composing department of the Conservatory of Music. And so he learned how to compose rather than perform, just due to his physical injury. When he was in med school, he ended up with being internal medicine or received those under internal medicine. But his specialty is actually musicians injuries. And earlier on, he wanted to set up something called In Musicians Clinic to solve some of these or address some of these musician injuries. And this was 1986, and he asked me to, come along for the ride. Initially I said no, because if you have electrical engineer or a lawyer or musician is a fine lawyer. Is that difficult? You really have to your audiology. I think all of our colleagues will agree that musicians are a difficult component of the hearing impaired population and it takes special kind of orientation. And of course, the engineers are right there as well. The person who comes in and says, I think if you tweak this at 1553Hz I think I’m going to be okay. That kind of a person. So, yes, they’re that difficult group. And that’s why I said no. But he’s bigger than I was. And he got me a little bit drunk and said, okay, I’ll come out and look at it and see what we could do. And the first patient I saw was a really interesting patient. He had come in initially with rest and arm problems. He was a violinist. Sawing away at the violin. but he also had tinnitus in his left ear. Of course, he’s holding your noise generator by his left ear. To make a long story short, I was hooked. I found that the solutions and the forms of assessment that were reasonable that I could do as an audiologist were exactly everything I’d ever learned in audiology. So you had to know about critical bandwidth, real acoustics reception issues, and how the cochlea functions of what we knew at that time about tinnitus, which was, of course, before Joshua Bobson Hazel’s 1993 publication. So tinnitus masking was quite rudimentary, but every element of what we learned in school was very useful. And of course, as I said before, the acoustics or the laws of acoustics of a vocal track are the same laws of acoustics we learn in our little acoustics class. And it’s the same acoustics that we see in musical instrument. So to describe musical instruments or to understand what they’re hearing with their own musical instrument. It’s those same laws of ear, mold, room acoustics, or vocal fact acoustics that we can apply. And I actually have been part of the Musicians Clinics of Canada since the mid 80s. Even today, I see certain things. Interestingly enough, there was a bit of a change going on. And the musicians clinic in the 1980s and 1990s, a lot of it was physical injuries, overuse symptoms, so that a drummer would come in and he would be hitting too hard on a rim shot or a high hat, and he would have wrist and arm problems. And I recall one person in particular who read it in its Modern magazine. Modern drummer which is in existence today. I’m a . You have to wear hearing protection. So he went out and got his father’s industrial strength EAR foam plugs and started to put them on. And it lessened. Level of his playing, but it took off so many monitoring cues of his drum kit and so specifically his rim shot. So he started hitting harder on the rim shot than he needed to because he couldn’t hear it very well. And that resulted in wrist and arm problems. Well, the solution was to fit him with the proper type of ear plug, one of the flat, uniform earplugs of the air, the ER, in that case, ER-25, made by a manufacturer called Etymotic Research, Mead Killion’s company. And it gave him a better monitoring ability of his instrument at the same time, gave him sufficient hearing protection, and his wrist and arm problems went away. So there are some interactions between physical injuries and monitoring the what an audiologist can do. Recently, however, most musicians that we see at the musicians Clinic he specialists are stress related. Now, I think we’ve had two or three generations of students over the last 40 years almost grow up on knowing that. Have to wear hearing protection. They now learn about school, whether it’s at college or level. They have to learn about hearing protection and other health concerns that a musician may have. But most musicians nowadays are on the gig economy, whether they’re street performers or musicians or whatever, and they play in the park, whatever. The successful musician that in ridiculous economy may only make $16,000 a year. And in most large cities like Toronto, that’s below the poverty line. So there are major stresses on musicians nowadays that perhaps we didn’t have as much in the 1980s or 1990s. Inflation has really, especially the rents and the cost of housing and food has really skyrocketed of late, and many musicians don’t know where their next skill will come from or whether they can be rent on a certain month. So you can’t look at a musician and just. Look at the hearing in isolation. You have to look at the All Be. And so a lot of what we do at the Musicians Clinic is stress reduction. Now, in the 1960s, for those of you that remember the 1960s, there was big ads in the newspaper. You remember the 1960s, big headlines saying, Stress the Big Killer. And they were referring to how stress can affect your heart, your lungs, your kidney, your liver. But of course, it didn’t say anything about hearing. But actually, in 2009 and another article of 2010. So more than a decade, a year a decade ago, not in the audiology journals and in the cell biology journals, the mechanism for how stress may affect your auditory system came out, and it turns out that high levels of stress move that your adrenal glands will emit cortisol, a stress hormone. Through a complex biochemical process, your cortisol gets into the brain and creates high. Levels of glutamate. Glutamate, we know, is one of the important neurotransmitter substances in our hearing mechanism. And it turns out that high levels of glutamate, whether it’s caused by loud noise or caused by stress, is identical at the smallest molecular level, and in both cases, calcium ions rushing into a cell, starting or beginning the depolarization or cell death process. So it turns out that people that are very stressed could have things like tinnitus. Now, these are people not with the hearing loss, not like you expect a 70 or 80 year old person to have maybe the tinnitus, but I’m talking about a 19 year old or 20 year old young musician just starting out with a lot of stresses after his life. And they have very high levels of cortisol in their body, for good reason. In at least in North America, musicians are not well respected and certainly are not well paid, but they have high levels of cortisol. Reading high levels of Glutamate and they come in tinnitus. So a lot of what I do now is to resolve the tinnitus, not just using masking perpetuation, not acknowledging that it’s an increase in central gain, as it would be with other forms of tinnitus, but more importantly, stress reduction techniques. And now Canada marijuana is legal and that can be useful, although are going to get involved with this. I know that 38 states in the United States have some degree of legality of marijuana as well, depending on their policies. But marijuana is made with two things the THC, which is the Stoning agent. And there is no benefit to that. There never has been any research benefit with Stoning agent, the THC, but there is a lot of research suggesting that the CBD or the Cabinoid can be very useful at suppressing tinnitus, suppressing stress, helping sleep deeper and longer. Which has positive effects. And there’s research also done by one of the physicians, musicians clinics of Canada, Dr. Kath Patrell, that showed that high levels of cannibinoidal CBD and that’s why we call it CBD, high levels of CBD of 30 or 40. Milligrams per dose, but very, very low levels of THC the Stoner agent, let’s say less than 2.5 milligrams per dose, can be very, very useful for many people. So many of my young musicians have this CBD that help maybe in the form of an oil, perhaps, that they take before they go to bed. That helps them sleep deeper. Sleep longer. And their overall stress level is lower. So audiology is kind of bordering now, more so than ever before. On the pharmaceutical side of things, at least in Canada, it is with CBD. There are so many chemical ear muffs as well. Coming down. Pipeline that we’re getting into otoprotectants. But of course, with those, you have to be very careful because it’s the dose that matters. So I can talk about NAC LNAC, for example, which has been known for years and years and years with all sorts of people. I can suggest that they try NAC, but unless I tell them what the dosage of NAC it’s problematic. Too much is no good. Too little is no good. There’s usually a sweet spot. And so, as the research comes out about these otoprotectants, these chemical earmuffs, these pharmaceuticals, that can be very useful. There’s an article, actually, that’s a headline article in this month Canadian Audiologist. And for those that don’t know my many roles, I’m the editor in chief of Canadianaudiologist.ca. It’s one word and it’s free, and it’s the official publication of the Canadian Academy of audiology. And if you listen to this, after the current issue is no longer there, go to past issues and pull it up by someone named Colleen LaPrel. Colleen is a true giant in our field, and she’s in the University of North Texas in Dallas, and she’s written a wonderful article for us about pharmaceuticals and how that can mitigate future hearing loss, and not just hearing loss, the things that go along with hearing, the genetics and other negative things as well. You mentioned some things about the Canadian audiologist, but I know you’ve been extremely active in the development of audiology across Canada, and particularly with the Canadian Academy of Audiology. The Canadian Academy of Audiology started about 18 years ago by now, just shortly after the but much after the American Academy of, and I think thank them because it was some of the people like Dr. Jim Jerger. Of the American Academy of Audiology that is very instrumental in helping us get the Canadian version off the ground. The Canadian Academy of Audiology as my journal, I’ve alluded to. We do have annual conferences. We have many position and policy papers, and the papers are very high level and very well thought out. So we, we have even though over the counter hearing aids has not yet hit Canada and may never hit Canada, we do have a well thought out, well considered opposition papers on that topic. We’re looking at ones on the, relationship if any, between cognition and untreated hearing loss, which there’s, according to recent achieved results from Dr. Frank Lin from Johns Hopkins University. There hasn’t been much of a relationship it doesn’t show much of a relationship between cognitive decline and hearing loss other than hearing better will help you think. Better. That is true, but we have position papers on that. So the Canadian Academy of Audiology has been very supportive of those endeavors. Within the Canadian Academy of Audiology, as I said, we do have many departments, many wings that have various orientations such as vestibular group, we have a small growing CAPD group. We have a larger application group. That seems to be my interest as well. We don’t have as large of musicians at hearing loss performing artists and hearing loss prevention as I would like to see. But I think you’ll see that in the future. Well, what you’ve also done is with the American Academy of Audiology as well, ah, giving us some orientation and probably using those mathematics and linguistic skills to kind of hope focus us in. Maybe a little bit different direction and so on. Well, it is true. Over the years I have given many talks for the various conferences of the American Academy of Audiology and have written in some of their journals and their magazine Audiology Today. One of the topics that I have presented there several times which was I think, well received is not what you formally think of audiology or you would think of audiology, but you wouldn’t necessarily put it together. But I’ve done a lot of work and written book chapters on how you fit hearing aid differently to different languages. Now you have to analyze what is important about languages. There has been a little bit of work on that in the past tonal languages with having more low frequency applications. So you might have program one for English and program two for, let’s say, Chinese, which is a total language. Well, the tones are very. Meaningful. And they’re always on the lower frequency, either vowels or nasals. In both cases, they’re dissonant the lower frequency sounds. And so at an enhanced low frequency bandwidth of the frequency response, the Chinese versus English might be very useful. I extended that to something beyond the phonetic level. I’ve gone to the level the morphing, and also the level of sentence. So, for example, there are many languages around the world that are restricted by consonant vowel. Consonant vowel structure. Hawaiian, Japanese being another one of them. In Japanese, even if they borrow a word like McDonald’s into their language, they impose the morphology of Japanese onto it. So McDonald’s having two consonant side by side is a no no. So they would call Macono Bolo lottos if I said that correctly. Or handbag is another example. And no dobago, where you never have two consonants side by side in that language. Well, what that means, though, in terms of compression, is that you want to ensure that the compressor has a very quick release time compared to English, a much faster release time. So a required adjacent consonant, which might be of a lower sound level, has sufficient Audibility in the system. So that could be one of the other changes. Another change will be at the sentence level. So English being a subject verb, object language, we have objects at the end of our sentences, and we always run out of air at the end of the sentence anyway. It’s quieter. But if we have an object, especially a proper noun name john saw. Mary. It gets louder. But most languages, if we don’t have a noun or proper noun or object at the end of a sentence, it gets very quiet. So you take. Languages that are subject object verb oriented, such as, again, Japanese, Korean, Armenian, Turkish it goes on and on. There are many, many languages, languages that have that characteristic. They have very quiet levels at the end of a sentence. So when we talk about sufficient gain for soft level inputs, we’re not just talking about for soft speech, but we’re talking about sentence final speech in these languages. And so these languages would meet more gain soft level inputs on their compressor. Have we set them up then for English? So if we had a bilateral Marshall, I even see now some of the hearing aid software is actually asked some questions about are is this total? What language is the individual speaking? Almost. There’s a couple of other manufacturer software that seem to do that now. That is true, and that’s because of my work and my working with them. So you don’t have to really listen to what I just said or understand what I just said. But you said you’re Turkish and we’re automatically giving you more gain or soft level inputs being sentenced bible inputs. So that’s some of the stuff I present mostly at the American Academy Audiology have written about them. There’s actually one thing that something very interesting that just happened earlier this morning. I have written in the past about musical roads. Now, this isn’t really Audiology 101. Before Audiology 101, this is something that Junior High School, where high school kids can do the calculations once they take their first science course about the physics of sound. There are musical roads all over our world where grooves in the pavement are drilled into or parked into roads. Yeah, and I think you just did this for the Munich airport, as I recall. Exactly. These are cars going 100 or in the state, 60 miles an hour. And it plays a certain song. And so the Munich airport goes to the We’re October Fest celebration. And there’s a pathway now that leads from terminal one to terminal two at the Munich airport, where you could drag your bag, your wheels over a pathway and going four or 5 or 3 miles an hour, your own little walking speed. And as you drag your CP’s over, it plays Unprocessed or Roll Out the Barrel song. Roll out the barrel today. That sounds like something from Munich for sure, particularly with the October Fest and all their famous kind of beer halls and that kind of thing, you know. And and I think some of our first interactions was, I think, at one time at the at the Tinnitus meeting in Iowa, but. But probably the place we got to know each other a little more was when we were all partners in the Hearing Health & Technology Matters group. There were nine of us that were all involved in that. Many of us had our own little blogs and so on. And yours is still going and going rather well. But HHTM has been kind of a part of all of us at one time or another. Oh, most definitely. I do. Thank HHTM. Hearing Health Matters. Hearing health and technology matters. That’s what you have to ask for. It’s HearingHealthMatters.org You can get to them. But every week, or in my case, I’ve slowed down a little bit, I apologize. Every month I have another contribution, but there are contributions about busy issues. Gael Hannan has written wonderful articles about what it’s like to be a consumer of hearing aids. I, of course, have one called Hear the Music. Which is all about music and music related things. There are historical articles on there. There’s current events in our hearing aid industry at it’s a wonderful organization and for years every week we’ve come out with a new blog and it’s still going strong today and subscribe to that through an RSS feed and it’ll come to your, in many cases, new blogs. There was also a review of many patents that are found in that field. Just so many different aspects that people build and when we decided to move on from ownership there, Kevin Liebe has taken that that HHTM to a new level as well and also added the This Week in Hearing component to it, which I think kind of. Brings things into almost a different component of the new Holly had, Holly Hosford-Dunn, who hustled all of us to kind of put this together, I think did a fabulous job of organizing this. And that, of course, Wayne Staab was involved with that as well. Now, I understand that said, can you tell us a little bit about the tinnitus? Not the tinnitus, but the temporary threshold shift application that you set up that you have organized about ten years ago? I thought of the concept that wouldn’t be interesting instead of to be able to measure a TTS a temporary threshold shift. Now, of course, the practicing reality, you have your hearing tested. You have to go away someplace to have some music or some noise exposure. And very quickly after have your tested second time. And the difference. Between the first and second time being a measure of your temporary threshold shift. I thought, well, wouldn’t it be nice to have an app for that? And so I developed an app called Temporary Hearing Loss Test App and it’s available both on Android and iOS. Although I must admit, currently there’s a glitch in the background programming of it that I have to we do an update only working on older operating systems. Now, it’s not, unfortunately, currently available, but that will change shortly. But the idea behind it is that you listen to your phone and you play a 6000 Hz signal either to earphones or just normally with the loud speaker in a certain location and you reduce the volume. It’s no longer audible. So you find your threshold of hearing before at 6000. Go and do whatever it is that’s noisy, musically or otherwise. And then you come back and you hit a button, says test hearing again and same 6000 Hz signal comes off and you can release it with a little spear that you hand drag with finger and you find the softer sound and then it calculates the difference between the before and the measure of TTS. Now, temporary threshold shift is not necessarily, I shouldn’t say necessarily not an indicator of permanent threshold shift. I know that people throughout the 1970s and 80s, such as Dixon Ward had spent their entire lives, academic lives trying to find relationship between temporary hearing shift, temporary hearing loss that we all experience from time to time and future permanent hearing loss. There is no loan relationship. But one thing that we did find is that in order to have a permanent hearing loss down the line, you have had to have had some temporary hearing loss before at some point. So it can be used. in that sense that it has to be a precursor, not necessarily a predictor out. And so if you found with this TTS app, the temporary hearing loss test app, that there was no measurable and no significant TTS, then you knew that that location was not potentially damaging. You didn’t have the maximum dose. It means, of course, you have to watch yourself address the week. If you did go to a rock concert on Friday night, that’s cool and wear it thoroughly. Just don’t load your lawn on Saturday or Sunday. You get someone else to do it for you. But if you did have significant amounts of temporary threshold shift, that was an indicator that next time you’re in that army you should be wearing hearing protection. And then it links back to our musiciansclinics.com website to give you certain strategies to protect your hearing loss going forward. Well, I think that would be quite helpful to young musicians as they begin some of their career as well as some of the seasoned veterans. Now, as we begin. To kind of wind out our discussion Here. Marshall, how do you see the future of the profession? Maybe not just in canada, but the profession as a general overall view? I’m actually very positive about our profession. I know I’ve been in 40 years, so Think That I’d be a little bit Jaded here and there. And there are certain things that can be a little bit Problematical, such as the advent of over the counter hearing aids that many Audiologists, in order to make their rent and their salary, have had to refer to dispensing hearing aids as well or other accessories. And there are other financial pressures that probably Would not have been an issue years and years and years ago. But I think that Audiology is such a wonderful place to be because it’s at the crossroads of engineering, mathematics. Linguistics, psychology, perception. There’s not one field I can think of, really, where audiology doesn’t touch upon. I think people with a degree or training in audiology do so many things. I’ve done quite a bit of forensic work, for example, where I’m using much of what I learned in Audiology 101. I still run a full clinic, full offices, and I’m very busy seeing patients. There’s something about seeing a patient diluting a kid into stopping crying so that you could do a full auditory test so they’ll be happier about it and may want back for follow up five weeks later. I like working with musicians. I do see my share of non musicians as well. And the reality of the situation is that I probably see my share of other people in order to pay the bill so that I can see the musician. You do? Spend inordinated or disapproportionate amount of time working with musicians, but it’s worth it and someone’s got to do it. And I would say that how I view a musician or how I look musician can really only be made possible because I know everything I know from audiology, from how I was trained. So I see the teacher of audiology as very positive. I think the schools of audiology, at least in Canada, well subscribed to but it’s very difficult to get into these fields. I think that the majority of people that do graduate work for many, many years in this field and they’re very happy about it and they want to go to work at the end of a long day. With me, it’s 40 years later, plus four years later, I still enjoy going to work every single day. Yeah, I think that the I miss the most about patients is that not only do you see the easy patients, but. See the difficult ones, you see the ones in the middle, and you see the whole future of everything. And anyway, I certainly want to thank you for being with us today, Marshall, and enlightening us on how a mathematician and that a linguist can actually teach us a lot about how to maybe work with these musicians, but in addition to working with our regular patients. So again, thanks so much for being with us this week. My yet has been Dr. Marshall Chasin, audiologist at the Musicians Clinics of Canada and also a columnist in the Hearing Review, HHTM and a number of other places. I would encourage you to review some of his materials because they can enlighten all of us. Thank you for being with us today and. Thank you, Marshall, for being with us at This Week in Hearing. Thank you so much, Bob. Thank you, everyone. Have a nice day.