Monday, November 14, 2011

Music, The Brain and Education – Warren Duffer James, Montessori Life 17 no3 Summ 2005

Summary

Music is no longer bound by the limits of it source. The increase in recording technology has increased the amount of music a person can hear but has de-emphasized the needs for people to actively make music together. Making music together was an important activity in the past because your only option for listening was to play yourself or go to a concert, which was not always available. By making music as an activity, the line between performer and audience is blurred.

When performers play together, their brains process the same information at the same time. So essentially they are functioning as one brain while they are working together. Playing music by oneself is also beneficial as it activates different parts of the brain at the same time. Performing causes the brain to coordinate analysis of patterns with physical movement.

Fewer people are participating in acoustical performances but with the increased portability of electronic music players they are actually listening more. Because our society has changed the value of music from performance to electronic, should we re-evaluate how we teach music in schools?

First we need to identify music as organize sound. Then we need to accept that no one type of music is intrinsically better than another. Music is influenced on a cultural level and based on familiarity within a given style. Children however, are not predisposed to be able to understand one style of music over another. They can distinguish between many variances within our Western 12-tone scale, but it is only through exposure are that they are entrained to listen within our parameters. This repetition is of sounds is how the child’s brain learns to process music.

Music is brought into the classroom for a number of reasons. The more traditional reason is to train young people to become proficient performers, which is usually done by a specialist teacher in the music classroom. Another reason is the use of music to assist the brain in acquiring new information. In this case music is piped into the non-music classes in the hopes of increasing brain development. Finally, music can be brought into the classroom as a diversion or for entertainment factor.

Music engages the brain on multiple levels, especially training the brain to process information spatially. In order to support the statement that music can “make you smarter” we need to acknowledge that for any type of brain development it needs to be the “right” music for the “right” person. So what causes one child’s brain to light up will have no effect on another. We traditionally reference Mozart in affecting intelligence but in reality that is the implementation of our Western cannon.

When using music in the classroom there needs to be an emphasis on listening over hearing in context. Music played in the background just becomes noise that the brain will eventually filter out. However music illicits movement so active listening could also include a movement component. It is important to encourage movement and singing outside of the music class to create an active listening experience in which all can participate.

Active music making must be a part of our daily lives if it is to have any long-term effects. It needs to be inclusive of all students, genres, and other subjects. Students should be exposed to live performances as often as possible and encouraged to participate in music regardless of ability or performance anxiety. Music as background noise is not as effective as when students engage in singing and moving with the music. Teachers do not need to be leaders of music making, as the children should be interacting with the music on their own. Music in schools is not meant for a select group of people nor is it meant to “make children smarter”. It is meant to be enjoyed as a social activity and promote cohesion in the classroom.

Reflection

I see the influence of electronic music in my own classroom. When I ask my students how they listen to music their top answers are through personal music players and headphones. There is a disconnect from the social aspect of music making and as a result music becomes something which is only personal. When they get the opportunity to play as a group in an ensemble, a lot of them enjoy the group aspect of music making over the actual music they are playing. In this case we are not training elite musicians, rather we are creating a space where musical experience can occur.

I think an engaging teacher changes their learning goals based on the students readiness for the lesson. Sometimes I push my students to become proficient performers, but other times our goal is to have fun while playing an instrument. I do not think it is as segmented as the article makes it out to be. I do agree however, that students must be actively engaged in music and that we need to model this behaviour for them. If their brains are used to music being a constant background noise, we need to re-train them in a sense to actively listen and analyze music in the classroom.

I like how the article made the connection between music making and movement for brain development. I’ve noticed with my own students that when we clap, sing, and dance to the beat, they have a greater understanding of more complex rhythms. When they “feel” the groove we become better players collectively. I find the connection between movement, music, and brain activity interesting, and am going to try and incorporate it on a more social level in my classroom.

Sunday, November 13, 2011

Seeing Music?

Source: Schutz, Michael and Scott Lipscomb. "Hearing gestures, seeing music: Vision influences perceived tone duration." Perception 36 (2007): 888-897.

Summary
Michael Schutz and Scott Lipscomb created this study to settle the debate among percussionists: does the length of the striking gesture have any direct impact on the length of the resulting tone? They found that the stroke height used in playing a note on the marimba had no effect on the acoustic length of the note. However, gesture and visual information played a large role in the perceived length of notes, even when the acoustic properties between so-called "long" and "short" notes were indistinguishable. They concluded that "music is only music within the mind of the listener" and observed that effective musical performances must rely on both auditory and visual information. Performances heard in contexts such as recorded radio broadcasts and blind auditions rob "both the performer and audience of a significant dimension of musical communication."

Reflection
I was frequently reminded of this topic after hearing Michael Schutz speak at the Colloquy for Music Psychology and Neuroscience. As performers of any instrument, we need to consider every aspect of the musical performance from the audience perspective. While many pianists will protest at the notion that the piano is a percussion instrument, it is undeniable that the basic operation mechanisms of the the instrument are similar to those of some percussion instruments. Many issues of performance are based on the fact that piano tones decay immediately. For example, in passages where composers write a crescendo under a long held note, my students often have trouble imagining that the note is growing louder.

The solution to this is partly further development of the inner ear, but this type of phrasing could also be understood through the use of a physical gesture. I can remember the first time I encountered this problem as a student. My teacher asked me to sing the phrase, noticing how my physical gestures mirrored the character of the long note. This demonstration was very helpful when I returned to the piano; the way I used my breath and arms to conduct the note made it much easier to shape the long note at the piano.

Beyond the basic level of duration of notes, gesture can also enhance other musical events. While preparing for a concerto competition in which I performed the same concerto as three other pianists, I was advised to use physical gestures to set myself apart from the others. Rather than simply playing a quick passage note-perfectly, she guided me in using an arm motion that would assist in communicating the effect of soaring, both musically and visually. Of course, my performance had to be technically sound and expressive in order for these visual "extras" to have any effect.

There are those who would dismiss this approach as purely virtuosic and lacking in artistic depth. Indeed, without a solid performance, visual displays merely distract the audience. Yet the findings of this study clearly show that visual cues act as an aid to audiences, influencing the way in which we respond to auditory information. Perhaps what is needed is a fine balance of both audio and visual cues. "Virtuosos are masters at shaping the musical experience, which in this case means using visual information to accomplish that which is impossible 'in reality'."



Saturday, November 12, 2011

The structural neuroanatomy of music emotion recognition: Evidence from frontotemporal lobar degeneration


Reference:

Rohani, Omar, Susie M.D. Henley, Jonathan W. Bartlett, Julia C. Hailstone, Elizabeth Gordon, Disa A. Sauter, Chris Frost, Sophie K. Scott, and Jason D. Warren. "The structural neuroanatomy of music emotion recognition: Evidence from frontotemporal lobar degeneration." Neuroimage 2011, June 1; 56(3): 1814-1821.


http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3092986/?tool=pmcentrez



Summary:


Despite growing interest in the neurobiology of music, the brain mechanisms that are critical for processing emotion in music remain incompletely understood. Music is universal and highly valued for the powerful emotional responses it engenders: indeed, music activates brain circuitry associated with pleasure and reward and musical emotion judgments and brain responses are consistent amongst members of a musical culture. Certain music can specifically induce an intense arousal response in normal listeners, and this response is mediated by brain structures such as the amygdala and insula that have been implicated in other kinds of salient emotional stimuli. Deficits of musical emotion comprehension have been reported following focal damage of these same structures, located in the medial prefrontal and anterior temporal lobe.


Frontotemporal lobar degeneration (FTLD) is the name for a group of clinically, pathologically and genetically heterogeneous disorders associated with atrophy in the frontal lobe and temporal lobe of the brain. In the over 65 age group, FTLD is probably the fourth most common cause of dementia after Alzheimer’s disease, dementia with Lewy bodies and vascular dementia. Patients with FTLD frequently exhibit derangements of complex social and emotional behaviour. From a clinical perspective, investigation of musical emotion processing and its cerebral associations in FTLD has the potential to improve the understanding of the disease’s phenomenology, and the intrinsic network connectivity in the working brain.


A human brain showing frontotemporal lobar degeneration.


The idea behind this research was to investigate critical neuroanatomical associations of emotion recognition from music using FTLD as a disease model of brain network breakdown. The research included 26 patients with FTLD and 21 healthy control subjects with no history of neurological, or psychiatric illness. Recognition of four emotions (happiness, sadness, anger, and fear) from music, facial expressions and nonverbal vocal sounds was assessed using a procedure in which subjects were required to match each target stimulus with the most appropriate verbal emotion label in a four-alternative-forced-choice model. The music stimuli were short (approx. 11 s) non-vocal (orchestral and chamber) excerpts drawn from the Western classical canon and film scores. MR brain images were acquired in all FTLD patients at the time of behavioural testing, as well as voxel-based morphometry, a neuroimaging analysis technique that allows investigation of focal differences in brain anatomy.


On neuropsychological evaluation, patients with FTLD showed deficient recognition of canonical emotions (happiness, sadness, anger and fear) from music as well as emotional signals conveyed by facial and vocal expressions compared with healthy control subjects. Impaired recognition of emotions from music was specifically associated with grey matter loss in a distributed cerebral network including insula, orbitofrontal cortex, anterior cingulate and medial prefrontal cortex, anterior temporal and more posterior temporal and parietal cortices, amygdala and the subcortical mesolimbic system. This network of the brain is essential for recognition of musical emotion that overlaps with brain regions previously implicated in coding emotional value, behavioural context, conceptual knowledge and theory of mind. The study also found that amygdala damage was associated with impaired emotion recognition only from music, as opposed to emotion recognition of facial and verbal expressions.


Reflexion:


The ability that music has to affect and manipulate emotions and the brain is undeniable, and yet largely inexplicable. This research identified regions of the brain associated with music emotion recognition, including insula, orbitofrontal cortex, anterior cingulate and medial prefrontal cortex, anterior temporal and more posterior temporal and parietal cortices, amygdala, and striatum. Identifying the neural mechanisms of musical emotion helps us understand how the brain codes emotional value, and how emotional signals acquire meaning.


Following a similar idea, Petr Janata, associate professor of psychology at UC Davis' Center for Mind and Brain, mapped the brain activity of a group of subjects while they listened to music, and found that the region of the brain where memories of our past are supported and retrieved also serves as a hub that links familiar music, memories and emotion. His research may help to explain why music can elicit strong responses from people with Alzheimer's disease. The hub is located in the medial prefrontal cortex region — right behind the forehead — and one of the last areas of the brain to atrophy over the course of the disease.


In Rohani & al.’s study, subjects with frontotemporal lobar degeneration did not respond well to recognition of emotion in music, unlike Alzheimer’s patients in Janata’s study. This was caused by grey matter loss, including the medial prefrontal cortex region, which is linked to memories and emotion. Does memory affect music emotion recognition, or is it just contained in the same medial prefrontal cortex region as is emotion? How does music succeed in prompting emotions within us? And why are these emotions often so powerful?

Thursday, November 10, 2011

Images of Sonic Objects

Source:
Godøy, R. I. (2010, April). Images of sonic objects. Organised Sound, 15(1), 54-62. Cambridge University Press. Retrieved October 10, 2011, from Scholars Portal Journals
http://resolver.scholarsportal.info.myaccess.library.utoronto.ca/resolve/13557718/v15i0001/54_ioso

Summary:
Largely based on the theories of Pierre Schaeffer in his Traité des objets musicaux (1966), but also drawing on more recent evidence from the study of musical imagery and support from the theory of embodied cognition, Rolf Inge Godøy, Professor at the Department of Musicology, University of Oslo, argues that the “sonic object” is the most significant timescale of music with regard to human’s ability to form stable memory images of music (sonic images) from continuous sound.

First, Godøy gives some useful background information on musical imagery, which is defined as the “mental capacity for imagining musical sound in the absence of a directly audible sound source”. Placing musical imagery in the broader context of mental imagery, he explains that there is generally a “functional equivalence” between real-world perception and action and imagined perception and action. (For example, recalling the last verse of a song would take longer than the first verse because people usually scan through the song from the beginning.) Furthermore, neuroscientific research shows that mental imagery and real perception and action share much of the same neural substrate. Of particular interest in musical imagery is that auditory and motor imagery seem to be bidirectionally linked. (For example, when professional pianists listen to piano music, the motor areas of the brain are also activated. Vice versa, when the pianists see silent piano performance actions, they also mentally hear the music associated with those actions.) Then, putting musical imagery in the perspective of embodied cognition, which sees perception and cognition as intimately linked with sensations of movement, Godøy argues that body movements are integral to music and that sound-events should be “understood as included in some kind of gesture trajectory”.

All of the above background information helps to prepare the reader for Godøy’s ideas about the nature of sonic objects, which he defines as “holistically perceived fragments of sound, typically with durations in the 0.5 to 5 seconds range”. He justifies this timescale by citing research that shows that listeners can generally recognize salient musical features, such as style, rhythm, texture/timbre, modal/tonal features, and expressivity, within this 0.5 to 5 seconds range. He then points out that theories of memory support the idea of sonic objects as coherent chunks of sound that are perceived and imagined in the present moment (in a series of “now-points”). In this way, an entire piece of music is basically a chain of sonic objects perceived and imagined chunk-by-chunk, moment-by-moment. Godøy describes three types of sonic objects: 1) Impulsive, meaning abrupt attack followed by decay, 2) Sustained, and 3) Iterative, meaning a quick series of fluctuations (e.g. tremolo). Given the integral sound-gesture link in the embodied perspective, he remarks that the three types of sonic objects correlate well with impulsive, sustained, and iterative body gestures. And given the bidirectionality between motor and auditory imagery, Godøy believes the “kinematics and dynamics of sound-related actions can create images of sonic objects”, which carries the implication that action imagery can actually enhance musical imagery and, therefore, can potentially be applied in various contexts, such as musical practice, research, and education.

Reflection:
Though slightly difficult for me to digest, I still found this journal article quite fascinating. Having read a chapter titled “Imagined action, excitation, and resonance” by Godøy (2001) in a book called Musical imagery, which argues that “images of sound-producing actions… can enhance [the] capacity for imagining sonorous qualities” (p. 237), I was curious to find out if Godøy has written anything else on this subject more recently. As it turned out, he indeed has, and I chose this article because it offers more up-to-date information on musical imagery, a topic that I am deeply interested in.

First of all, I was not surprised at all to discover that auditory and motor imagery are linked; I can relate well to the experience of having the urge to move my fingers and “play along” when listening to other pianists performing pieces that I am acquainted with. Being a performer, I have absolutely no doubt that body movements are integral to musical experience. But Godøy’s suggestion that there is an important gestural component to sound would still have seemed a little strange to me had I not taken a course in conducting two years ago, which certainly made me much more aware of how gestures can accurately represent various sound qualities (with a lot of practice, of course).

What impressed me the most about this article was the fact that something as private and seemingly unobservable as imagery could be systematically studied and theorized upon so extensively. I think that Godøy backs up his argument about sonic objects convincingly. What I am primarily interested in, however, is whether action imagery would really prove effective in developing musical imagery in the context of mental practice, as his view implies. Up till now, I have rarely employed the strategy of mental practice myself. But I have always been taught that I must first know what kind of sound I want (in my “inner ear”) before I can experiment with various ways of pressing the keys that would get me closer to realizing that sound. So it seems to me that the music should come first and the action subservient to it. Nevertheless, I suppose that after some physical practice, the sound would become inseparable from the action associated with it, and, at this point, action imagery would be effective in bringing forth musical imagery. So perhaps one needs a certain amount of physical practice on a particular piece before action imagery can be used? Or maybe it would simply be best for one to start developing mental practice skills early on in one's training?

Reference
Godøy, R. I. (2001). Imagined action, excitation, and resonance. In R.I. Godøy, & H. Jørgensen (Eds.), Musical imagery (pp. 237-250). Exton, PA: Swets & Zeitlinger Publishers.

Wednesday, November 2, 2011

Memoirs of an Addicted Brain

Lewis, M. (2011), Memoirs of an Addicted Brain. A neuroscientist examines his former life on drugs. Doubleday Canada, www.randomhouse.ca
ISBN 978-0-385-66925-2


Recently, I heard Dr. Marc Lewis interviewed on CBC. He is a neuroscientist from U of T, now living and teaching in Holland. He was talking about his book Memoirs of an Addicted Brain, not fundamentally about music and the brain although Lewis has an undergraduate degree in music from Berkeley and is an avid sitar player. His personal story of drug addiction and his unusual way of describing the brain’s chemistry compelled me to buy the book. I couldn't put it down. Here is the link to the CBC interview. http://www.cbc.ca/thecurrent/episode/2011/10/10/addicted-mind 

Summary
In Memoirs of an Addicted Brain, Marc Lewis recounts his life as a drug addict. Originally from Toronto, he was shipped as a teenager to Boston to attend a boarding school. Homesick, bullied and missing the warmth and affection of his (extended) family, Lewis began to deal with his pain through cough syrup and alcohol.  He moved to Berkeley, California and became part of the LSD and heroin scene. Then, he joined his family in Malaysia and later Calcutta turning to opium. When he returned to Canada to become a psychologist, he stole drugs from medical clinics and was subsequently arrested. The book chronicles Lewis’ journey with drugs, addiction and healing. Lewis eventually recovered and became a professor of developmental psychology and then a researcher in neuroscience.

This extraordinary narrative is formatted around Lewis’ progressive drug addiction. Each chapter gives colourful and detailed explanation, intertwining  underlying emotional conditions with choices, as well as the prominent drug he was using at the time.  Lewis, an effective storyteller, distinguishes the effect of each drug on the brain: i.e. dextromethorphan hydrobromide (cough syrup), cannabinoids, LSD, PCP, heroin, opioids . The reader learns about brain structures, functions and locations in both healthy and drug-polluted brains. Lewis details healthy neurotransmission and then what happens when dopamine and serotonin are regulated  intrusively with addictive drugs. He relates the VALUE and THRUST feedback cycles, the neurological basis for cravings that can take hold in the mind and in the brain. Lewis shows the reader how the addict’s brain, fertilized by the emotional potency of repeated drug experiences, crystallizes synaptic connections, tightening, rigidifying, constraining the choices (Lewis, 2011).

Marc Lewis believes that addiction is a corrupted form of learning and warns that the extensive flexibility of our brains is not infinite. Synaptic sculpting, how learning occurs, uses up brain flexibility. He states that synaptic shaping is self-promoting and self-reinforcing and can be accelerated by strong emotions. Addictive drugs are addictive because of the strong emotions they release with meaning,  value and the narrowing in of how the world feels (Lewis, 2011).

Lewis admits that once addiction sets in, the brain never returns to the state that preceded it. He would counsel young people in this way:  Say no in a way that catches and takes hold. Pursue things that are real and have meaning rather than illusions and imagined values.

 Reflection
Memoirs of an Addicted Brain is a valuable resource for understanding neurochemistry and the impact of chemical invaders or mimics. Lewis gives a comprehensive yet accessible explanation of neurological structure, function and location. It was easy to visualize baselines and distortions because Lewis relayed the brain as a functioning neighbourhood with each part interrelated doing its specific task i.e. bridging, gate keeping and because he offered the neuroscientific information cumulatively within the context of his growing need for control.

It is a known fact that many musicians struggle with drug addictions. In fact, yesterday in the Ottawa Citizen, Phil Dwyer, saxophonist/pianist/composer candidly describes how he has struggled with serious addiction and mental health issues. http://blogs.ottawacitizen.com/2011/11/01/the-phil-dwyer-interview-part-iv

One friend who toured with a rock band for many years, admittedly said that the touring lifestyle got boring, predictable and there was lots of waiting around. Alcohol and drugs were a way of making it more bearable.  Music and drugs seem attached –at- the -hip in the rave culture. The dissociations or amplifications with reality may be potentiated through music. Certainly musicians of all genres have died of drug overdose.

Memoirs of an Addicted Brain makes me think about the relationship to music and addiction in another way. As music educators, how addicted do we become to “winning” the music competition. The craving feedback loop which is based on needing control and needing the fix may propel our choices – the wanting, the needing  for our own sake of feeling good and needing control - pushing children at a  young age to competitive, neurotic and even inappropriate goals without the care full nurturing, love, and magical experience of music’s aesthetic and spiritual draw. Do we become addicted to the applause of a performance?

Not for one moment did I need to point the finger at Lewis in his courageous autobiography. The neural activity spoke for itself and potentially lies in each one of us. Addiction is insidious, formed day by day, synaptic rut by synaptic rut,  with habits that are formed by personal choices, ultimately a result of what we deeply think about ourselves. We are all vulnerable.



Sunday, October 23, 2011

Your Brain on Improv

Source:

http://www.ted.com/talks/lang/eng/charles_limb_your_brain_on_improv.html

About the Speaker: Charles Limb is an Associate Professor, Otolaryngology, Head & Neck Surgery, and Faculty, Peabody Conservatory of Music. He combines his two passions to study the way the brain creates and perceives music. He's a hearing specialist and surgeon at Johns Hopkins who performs cochlear implantations on patients who have lost their hearing.

(http://www.ted.com/speakers/charles_limb.html)

Overview:

The idea that artistic creativity is a product of the brain has inspired Limb to explore the connections between the two. By having jazz musicians and rappers demonstrate their creativity through improvisation and free-style rapping while in an fMRI scanner, Limb is able to see activity in specific areas of the brain. Most of the experiments took place at Johns Hopkins University while some took place at the National Institute of Health.

Summary:

How is the brain able to be creative?

For this experiment, a 35-key MIDI keyboard designed with minimal interference was used in the fMRI scanner. MIDI signals from the keyboard were sent out through the interface and into the computer for analysis.

This study consisted of three experiments. All three experiments involved memorizing a piece and then improvising immediately afterwards. Brain activity (blood flow increase or decrease) was then observed and discussed.

The first experiment had professional jazz musicians memorizing a particular piece of music and then improvising the same piece using the same chord changes. The results showed an increase in activity in the medial prefrontal cortex (self-expression) while the lateral prefrontal cortex (self-monitoring) had a decrease in activity.

In the second experiment, Limb explored what brain activity occurs when musicians are “trading” music back and forth with a 12 bar blues piece. One jazz musician was in the fMRI scanner having a musical conversation with another musician, Limb himself, in the control room. The results showed that the musician’s Broca’s area, language area, as well as the brain area potentially connected to expressive communication were activated. These results provide some insight to the claim that music is a language.

The third experiment was to think about the connections between free-style rap and jazz. Free-style artists first memorized a rap written by Limb (control conditions). With the help of various cued words, the artists then created their own version of the rap. From a combination of four rappers’ brains, similarily to the previous experiments, language areas were shown to be active. However, when free-styling occurred, there was an increase in brain activity in the visual areas as well as cerebellar activity (i.e.motor coordination).

The connections between the brain and creativity are insightful, but because these results are preliminary, it is Limb’s hope that in the next few decades, we will be able to see more comprehensive studies that demonstrate this connection.


Response:

It really is amazing to think just how a jazz musician such as Keith Jarrett, can improvise on a piano for an entire concert. It is also interesting to see the results that one might expect when the participants are expected to improvise laying down in an fMRI scanner. Seeing the results of this preliminary study, the brain areas that are affected when performing a creative task, I am led to some questions for future studies.

1. What brain activity would occur if participants did not have a memorized piece, but were given a new piece to improvise?

2. What is the definition of creativity? For example, some people are able to think creatively almost immediately while others are able to be very creative with more time and thought. It would be interesting for researchers to consider this concern in their future studies.

As researchers try to find the root of creativity in the brain, I think about how this and future studies relate to children and creativity. Though the results are preliminary, the connections that are involved between the brain and creative tasks provide some insight into the pedagogical implications for music education. I look forward to hearing about these future studies.

A Larynx Area in the Motor Cortex: study dispels previous conclusions that laryngeal function generalized across lip, jaw and tongue areas of brain

Source: Brown, S., Ngan, E., & Liotti, M. (2008). A larynx area in the human motor cortex. Cerebral Cortex, 18, 837-845.


Have you ever wondered how your voice actually works? If you have, and looked into it, you will have discovered volumes of information on laryngeal function, aerodynamics, physics, and neurology to name a few. Vocal function is a field that has only recently come under the microscope, quite literally. Though Hipocrates speculated on the workings of the human voice as early as the fifth century BC, it wasn’t until Manuel García thought to shine a mirror down someone’s throat in 1854 that the living voice was seen in action. García presented his findings to the Royal Society of Medicine a year later. Voice medicine has been a slow and late bloomer compared to other specialties, but with increasing interest and new technologies there is unprecedented growth in a number of voice specialties. It’s no wonder than that neuroscientists have “answered the call” (vocally speaking) and begun exploring voice function where it really begins: in the brain.


Article Summary:

Until this study was concluded in 2008, it was widely believed that laryngeal control was spread across several areas of the motor cortex that corresponded to motor control of the articulators – the lips, tongue and jaw. This was based on the motor homunculus (pictured below), which was established by Wilder Penfield and others through neuro-stimulation in the 1930’s and 40’s.

The absence of a specific laryngeal centre in the brain is a pretty substantial thing when you get to thinking of the significance of phonatory communication to the human race. It is, after all, one of the most obvious evolutionary triumphs setting us apart from other species on this planet. Thus, Steven Brown of the McMaster Institute for Music and the Mind conducted a study of 16 individuals using fMRI imaging with a primary goal to define a somatotopic location for the larynx area.

This article described 4 of 6 oral tasks that the participants were asked to do while scanned. The tasks ranged from singing on a “schwa” vowel to performing glottal stops (ie. forced adduction of the vocal folds), lip protrusion and tongue movements. Each activity was done in a repeated pattern with breaks in between, this specificity requiring the subjects to attend a training session before their scan.

There were two principle findings in Browns analysis of the data gathered. First was that the peak activations in the motor cortex for glottal stops and those for phonation were nearly identical in all 16 subjects. This yields a strong argument that there is a common motor region underlying adduction (closing) and abduction (opening) and tensing/relaxing of the vocal folds – the major functions of the intrinsic musculature of the larynx. Brown refers to this general region as the larynx/phonation area (LPA) of the motor cortex. There was also activation in a superior temporal region known as “cortex of the dorsal Sylvian fissure at the parietal-temporal junction” (Spt). The Spt has been previously connected to audiomotor integration for vocal production, but Brown’s data revealed for the first time that this area could be activated in the absence of vocalization (during glottal stops), vocal imagery, or strong auditory stimulation – though Spt activity was significantly stronger during vocalization. It is unclear if the activity was due to auditory stimulation, increased laryngeal activity, or perhaps a combination of the two.

The second finding was that the human LPA is not ventral (in front of) the tongue area as was previously suggested in multiple sources. The LPA is actually located in a dorsal position (or behind) the tongue area and directly across from the lip area in all 16 subjects. Brown concludes that the human larynx area appears to have a novel localization next to the articulators and is much further away from the pharynx area than might be expected.


Reflection:

This was quite an ambitious read for me as I am in my first months of study of music and the brain. I was lead by my interest and investment in vocal function especially as it relates to vocal disorders. In the world of vocal disorders, nodes and polyps (physical abnormalities of the larynx) are what a singer often associates with voice disorders, however there are many vocal disorders that are neurological. Spasmodic dysphonia is one such disorder involving hyper function of the laryngeal muscles. Patients with spasmodic dysphonia deal with what seems to be a mis-firing of the larynx resulting in over adduction (too much closure) of the glottis. Sadly, this disorder has a fairly high incidence in professional voice users.

Though recent research into this disorder has shed some light on the cause (a problem in the feedback loop between the brain and organ with the dystonia), in many cases treatments only marginally restore function, and all treatments centre on the larynx instead of the brain. The most standard treatment is botulinum toxin injections (BOTOX) into the muscles that are spasming. These injections last about 4 months and often immobilize the muscles so much that singing isn’t possible. Other treatments include cutting the nerve to the voice box and attaching another nerve, changing the shape of the voice box, and speech therapy. Non of these treatments are particularly reliable from patient to patient.

Spasmodic dysphonia is just one example of several neurological disorders effecting the larynx. My hope is that Brown’s research will eventually lead to easier identification and diagnosis of neurologically based vocal dysfunction, and perhaps steer specialists toward treatments that include the brain.

Reading this article has helped me understand why the brain is left out of the treatment of these disorders and given me hope that the vocal specializations community is on the threshold of understanding the brain as it relates to vocal function in a whole new way.