I keep a regular yoga practice. I mainly practice at home, since it's free to do there, but I also attend yoga classes regularly at a good studio. I tend to do yoga about two to three times a week. However, this past spring semester, I ended up only practicing once a week, at most. So, I got decently out of shape from what I'm used to and I ended up hurting my left hamstring, somehow. What sucked the most about this was that my left leg has always been more flexible than my right leg, while my right leg tends to be stronger, so I was usually able to do hand-to-foot pose and this one-legged arm balance with my left leg pretty easily, while I still struggled a little with the right. However, this summer, while I've been trying to nurse my left hamstring back to health, my sides have reversed. I'm still not able to do these poses, or others like them, with my left leg, but I've gotten them down with my right.
So just today, while I was practicing at home, I realized that I've been so careful with my left leg this past few months that I've actually let it become weak. I've stopped trying to engage the muscles on that leg as much because of the injury. Of course, this is not helping recovery at all, so today, I started forcing that leg to pull it's weight, and while my hamstring still isn't totally better, I actually got my full trikonasana on the left side back today and my hamstring feels better now than it has in a long time. I'm sure the more I focus on working the muscles on my left leg, the better it will get, and I will be back to my normal yoga practice pretty soon.
This little experience with my hamstring really reminded me of my vocal recuperation, probably because I had a conversation with another singer dealing with their own voice disorder just this week. See, the thing is, I was acting like my hamstring was still injured, even though it's been months since the actual injury. My hamstring is quite likely healed up, it's just healed tighter than it was before. Because of this tightness, I've been avoiding really using it in yoga, making modifications on the left side for any hamstring-intensive pose and just allowing my lunge on that side to kinda go out of form. In essence, I was allowing my muscle to stay weak just because I was still acting like something was wrong with it well after it was healed up. In an earlier post, I said I had a hard time learning to trust my voice after it was healed up, because I felt like my voice had betrayed me by being injured. But I've talked to a few singers out there dealing with injury who have the added issue of still feeling like their voice is injured even after therapy is completed and they're given a full bill of vocal health by their team. So they're still fighting with their voice and letting it do the wrong things because they still think it just doesn't "work right," even though it does. It's a mind game, isn't it?
What these injuries really do to us is force insecurity upon us, so naturally, our reaction is to defeat the insecurity. Attack it full on so that we can get past it as quickly as possible. But when this tactic burns out, as it often does for many people out there, we start to retreat into the insecurity, allowing it to defeat us and beat us down until we give up. This can lead to regret and perhaps even bitterness for so many of us, and maybe we find the fire to fight again and maybe we win, but what if we just changed our perspective of this insecurity? What if, instead of fighting, we decide to accept this weakness that has been thrust upon us and still decide to be kind to ourselves? And what if, by being kind to our whole new self, insecurity and weakness and all, we learn how to patiently and diligently work through our injury, not by forcing ourselves to be as we were before, but by moving toward being someone new and different because of this experience? What if all we need to do is realize that healing doesn't typically mean going back to how things were before, but it can mean becoming better than we were before?
I suppose saying I'll get back to my normal yoga practice is a bit of a lie, because before this injury, my right side was more inflexible than it is now. If my left side is restored to it's former, flexible state, my whole body will actually be more balanced than it was before this. Just like how, even if my voice is only better because of being healed and the glories of vocal technique, I'm a better, more joyful singer because there was a time when singing was taken away from me. So to all those out there recuperating from any injury: May recovery make us all stronger, more balanced, and more joyful; may we be kind to ourselves and patient with our injury as we build our strength back up; and may we all realize that we will never be the same...and that can certainly be a good thing.
New Voice, New Career
Thursday, July 26, 2012
Why yes I DO like school, thank you very much
There's a common statement I tend to hear from certain people when they find out that yes, I am going back to school for yet another graduate degree: "You must like school." This statement is always delivered with a bit of snark and a slight roll of the eye, and it is usually said by people who say they were "never good at the whole school thing." That phrase is almost always followed up with the person explaining how great their (insert job title with major company) is and that they get paid (insert regular hourly wage/typical management salary) and they never needed a degree to do it. The rather clear subtext to this exchange is thus: "You poor, nerdy sap. You must be in school because you're avoiding the real world. You should suck it up and just get a job like everyone else."
What I find the most interesting about these exchanges are the implicit assumptions that are made about people who seek additional degrees at all. The main assumption tends to be that anyone who gets a degree higher than a bachelor's or a second bachelor's is a "career student;" you know, someone who's just avoiding adult responsibility by staying in school as long as possible. I find this assumption interesting in light of two facts: The fact that I have been out of school for several years now and have been an independent adult through all of those years, and the fact that there are a lot of health/medical professions that require a graduate degree for licensure. I know I can't expect the general populace to know what requirements there are for certain professions, but why do some of these folks not drop the snark when I tell them that? Why not just trust that those degrees are required because there is a vast body of knowledge and many hours of training required to do the job effectively? People trust MDs are valid professional graduate degrees, so why not trust that physical therapists, occupational therapists, physicians assistants, audiologists, speech-language pathologists, etc., need advanced knowledge to effectively do their job?
But it's the implicit insult that really gets me: "Nerd." Now, I know that in today's society, the term "nerd" has been usurped to mean anyone who's really, really into pretty much anything and is not really seen as an insult anymore, but in this setting, it's intended as one. Perhaps there are just too many grad students out there who are intellectual snobs. Maybe these folks have encountered so many of those snobs that they get all defensive and mistakenly think someone with multiple degrees is automatically a snob. I can definitely sense a bit of insecurity from the other person in this exchange. Maybe they always wanted more out of life, but gave up on their dreams. Maybe they always struggled in school and felt inferior to a sibling or friend who always found school easy. Maybe they did well in school, but only because of a near-abusive "tiger mom," and so they hated school as much as they were good at it. As much as I believe insecurity is nothing to be ashamed of, I also believe personal insecurity is never a valid excuse for making another person feel like crap. I believe this as much as I believe that salaries and job titles do not define the intrinsic worth of another human being.
My reactions to these situations have never been the best. I usually end up explaining the good employment prospects and the typical starting salaries in the field, but this is in stark contrast to the belief I just stated above, isn't it? So I end up feeling put down, but also a little dirty for defending my life decisions based on their criteria of self-worth. The thing is, that is not my criteria.
So, after having one too many of these situations in the past, I have decided to arm myself with a response I can feel good about (which will be truncated in real life):
Why yes, I do like school. I like to learn. I enjoy broadening my mind and discovering new and exciting things that I never knew about before. I like the idea of helping forward the advancement of society and human knowledge through research. I like the pragmatic side of this new field, where I get to help an individual who is struggling with a disorder that keeps them from effectively communicating. I like school. I like that it is not only an avenue through which I can pursue my dreams and sharpen my mind, but it is also a safe place to learn, try, discover, fail, try again, and, ultimately, succeed. I like learning, and I like that I will continue to learn, grow, and develop throughout my life thanks to the mental training higher education has given me. With all the people in the world who use knowledge and education to keep others down, I like that I am becoming someone who will counter those greedy individuals, and who will use her knowledge and education to help others in need of it. I think education provides me with a value beyond just a salary and job title. It provides me with a sense of purpose and direction and the ability to accomplish my goals. Isn't that ultimately what we are all searching for?
What I find the most interesting about these exchanges are the implicit assumptions that are made about people who seek additional degrees at all. The main assumption tends to be that anyone who gets a degree higher than a bachelor's or a second bachelor's is a "career student;" you know, someone who's just avoiding adult responsibility by staying in school as long as possible. I find this assumption interesting in light of two facts: The fact that I have been out of school for several years now and have been an independent adult through all of those years, and the fact that there are a lot of health/medical professions that require a graduate degree for licensure. I know I can't expect the general populace to know what requirements there are for certain professions, but why do some of these folks not drop the snark when I tell them that? Why not just trust that those degrees are required because there is a vast body of knowledge and many hours of training required to do the job effectively? People trust MDs are valid professional graduate degrees, so why not trust that physical therapists, occupational therapists, physicians assistants, audiologists, speech-language pathologists, etc., need advanced knowledge to effectively do their job?
But it's the implicit insult that really gets me: "Nerd." Now, I know that in today's society, the term "nerd" has been usurped to mean anyone who's really, really into pretty much anything and is not really seen as an insult anymore, but in this setting, it's intended as one. Perhaps there are just too many grad students out there who are intellectual snobs. Maybe these folks have encountered so many of those snobs that they get all defensive and mistakenly think someone with multiple degrees is automatically a snob. I can definitely sense a bit of insecurity from the other person in this exchange. Maybe they always wanted more out of life, but gave up on their dreams. Maybe they always struggled in school and felt inferior to a sibling or friend who always found school easy. Maybe they did well in school, but only because of a near-abusive "tiger mom," and so they hated school as much as they were good at it. As much as I believe insecurity is nothing to be ashamed of, I also believe personal insecurity is never a valid excuse for making another person feel like crap. I believe this as much as I believe that salaries and job titles do not define the intrinsic worth of another human being.
My reactions to these situations have never been the best. I usually end up explaining the good employment prospects and the typical starting salaries in the field, but this is in stark contrast to the belief I just stated above, isn't it? So I end up feeling put down, but also a little dirty for defending my life decisions based on their criteria of self-worth. The thing is, that is not my criteria.
So, after having one too many of these situations in the past, I have decided to arm myself with a response I can feel good about (which will be truncated in real life):
Why yes, I do like school. I like to learn. I enjoy broadening my mind and discovering new and exciting things that I never knew about before. I like the idea of helping forward the advancement of society and human knowledge through research. I like the pragmatic side of this new field, where I get to help an individual who is struggling with a disorder that keeps them from effectively communicating. I like school. I like that it is not only an avenue through which I can pursue my dreams and sharpen my mind, but it is also a safe place to learn, try, discover, fail, try again, and, ultimately, succeed. I like learning, and I like that I will continue to learn, grow, and develop throughout my life thanks to the mental training higher education has given me. With all the people in the world who use knowledge and education to keep others down, I like that I am becoming someone who will counter those greedy individuals, and who will use her knowledge and education to help others in need of it. I think education provides me with a value beyond just a salary and job title. It provides me with a sense of purpose and direction and the ability to accomplish my goals. Isn't that ultimately what we are all searching for?
Friday, July 13, 2012
Physics of Sound Series: Harmonics and fixed strings and open-closed tubes, oh my!
So, we've got the vocal folds acting like a fixed string with multiple resonant frequencies called harmonics, but before we go further, I realized there was some terminology that I should go over. Remember how the actual sound wave produced from vocal fold vibration is far more complicated than that of a single string? That's mainly due to the motion of the lamina propria, but even single strings can produce complex sound waves. This is a wave pattern that is created from the interaction of multiple frequencies known as harmonics. If you have several, or even thousands, of simple sine waves that are harmonically related, you've got a complex periodic sound wave. Periodic means it still has a predictable pattern, as opposed to complex aperiodic waves, like white noise. But the linguistic signal contains both periodic and aperiodic waves. Periodic would be vocal sounds, like vowels; aperiodic would be like unvoiced consonants like /s/, and a combination of periodic and aperiodic happens during a lot of voiced consonants, like /z/. We're just going to focus on complex periodic waves for the purposes of understanding resonance more fully. Complex periodic waves can be broken down into their simple sine wave components by using something called a Fourier transform. We certainly won't go through the math for all of that, but just know that all complex periodic waves are made up of simple sine waves, and even though the vocal folds create a more complicated sound than a string does, we're going to continue with the string comparison cause I think it makes everything so much easier to visualize.
The thing about vibrating strings fixed at both ends is that they have a fundamental resonance of 2 times the length of the string. This just means that one-half of a wave can "fit" on a string at any given pass along the string. It also means that the string will vibrate at both even and odd harmonics of the fundamental. This can be represented mathematically if we use our knowledge of frequency = velocity divided by wavelength. In this basic case, we're going to consider velocity to be the speed of the wave being produced, and in the human voice, that speed is determined by the tension and mass of the vocal folds. So when the folds elongate, tension increases and mass decreases resulting in a high frequency of vibration (cool, huh?). And the wavelength, thanks to the half-wave resonator we're working with here, will be two times the length of the string (or folds). Using this equation and setting our speed at 340 meters per second, the approximate speed of sound at sea level, we can figure out the harmonics of a 1 meter string. The fundamental frequency would be 170 Hz, the first harmonic would be 340 Hz, the second harmonic would be 510 Hz, the third 680 Hz, the fourth at 850 Hz etc. This sound wave (up to the fourth harmonic) would sound like this:
The thing about vibrating strings fixed at both ends is that they have a fundamental resonance of 2 times the length of the string. This just means that one-half of a wave can "fit" on a string at any given pass along the string. It also means that the string will vibrate at both even and odd harmonics of the fundamental. This can be represented mathematically if we use our knowledge of frequency = velocity divided by wavelength. In this basic case, we're going to consider velocity to be the speed of the wave being produced, and in the human voice, that speed is determined by the tension and mass of the vocal folds. So when the folds elongate, tension increases and mass decreases resulting in a high frequency of vibration (cool, huh?). And the wavelength, thanks to the half-wave resonator we're working with here, will be two times the length of the string (or folds). Using this equation and setting our speed at 340 meters per second, the approximate speed of sound at sea level, we can figure out the harmonics of a 1 meter string. The fundamental frequency would be 170 Hz, the first harmonic would be 340 Hz, the second harmonic would be 510 Hz, the third 680 Hz, the fourth at 850 Hz etc. This sound wave (up to the fourth harmonic) would sound like this:
Now that we've compared the vocal folds to strings, what do we have to compare the vocal tract to? An open-closed tube! ...which is not that exciting at all. But what the vocal tract does is pretty darn exciting. Of course, the vocal tract itself can change it's shape for communication and such, but the open-closed tube is a good simplification of what the basic function of the vocal tract is. An open-closed tube is a quarter-wave resonator, as opposed to the half-wave resonator that the string up there is. So what does that mean? A quarter-wave resonator means that only a quarter of the wave can "fit" during one pass through the tube. So this resonator only vibrates at odd harmonics of the fundamental frequency. So, if we look at that 170 Hz frequency produced from that meter-long string up there, The open-closed tube resonating at this fundamental 170 Hz would have a length of 0.5 meters and the first harmonic would be at 510 Hz, the second at 850 Hz, etc. Notice something there? This tube is only resonating at even frequencies of the string up there. So what happens to the sound wave produced by that string as it passes through this tube? Well, it'll sound something like this:
File made with Audacity
Where did those other harmonics go? The tube ate them. No really! Well...it kinda-sorta did. See, the tube acts as a filter for that sound wave. Those missing frequencies, the ones that the tube won't resonate, are going to be filtered out due to destructive interference, while the frequencies the tube vibrates at are going to constructively interfere and exit the tube for us to hear. Yup, that's right. Without resonance, we wouldn't hear our own speech, much less a singer singing over an orchestra. Your voice is always resonating all of the time; it's just that opera singing requires a difference resonance than your speaking voice...obviously. We don't really sound like we're talking when we're singing, do we?
Now, I don't know about you, but I personally find the second audio file a little more pleasing than the first. The first one is objectively "richer," in the sense that it has more harmonics, but the second one subjectively sounds "richer" to me. I'm not really sure why, but I suspect it has something to do with the fact that I am physiology wired to find the sound of the human voice important, as are you, and so perhaps I also find sounds from an open-closed tube more pleasing? (And if you didn't find this to be true, you're really messed up! Just kidding.) And where this "pleasing" association would occur in the brain, I'm not sure. But I know my brain is associating the second file with a richer sound that I happen to find more pleasing, because the first sound has more harmonics in it for sure...I would know; I inputted the frequencies myself! But if you played those two tones for me without my knowing about the harmonic structure, I would assume the second one has more harmonics. The brain sure is one crazy organ, amirite? Of course, I digress, but this is an example of some of the stuff people are trying to figure out in terms of how we listen, pick out, and associate the speech signal into meaning in our lives all day long. It's some cool stuff, for sure. Perhaps I'll learn an answer to that soon and will update you guys.
Now, in a stationary tube, the harmonics are pretty fixed, but lucky for us, our vocal tract can change shape, length and configuration to produce a lot of different sounds. By changing it's shape, the vocal tract filters the same sound source differently, producing all of the different sounds we make in our languages and then some. Conveniently for us, it seems to do this pretty much on auto-pilot most of the time, like when we're speaking, or how the vocal tract lengthens when our voice drops in pitch (the larger cavity will resonant at lower frequencies and shorter at higher). The shape the tract takes determines which frequencies are amplified and which ones are dampened out. And this sets us up quite nicely to talk about formants next time, doesn't it?
Resources:
Raphel, L. J., Borden, G. J., Harris, K. S. (2007). Speech science primer: Physiology, acoustics, perception of speech (5th ed.). Philadelphia, PA: Lippincott Williams & Williams.
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