Blog post by Christopher Berg on "Virtuosity Unveiled"

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Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by David Norton » Sat Nov 18, 2017 1:49 pm

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by Ramon Amira » Sat Nov 18, 2017 5:07 pm

This is interesting, but as with many analogous essays is of dubious value from a practical standpoint. To try to incorporate scientific theory, mathematical studies, and even medical aspects - neurology, etc., and minutely detailed analyses of physical movements, into pedagogy, can be worse than useless - it is unlikely to have any beneficial effect but is very likely to have a detrimental effect.

I am reminded of the fable of the centipede who decided to figure out how he walked with all those legs. "Let's see . . . first I move leg #32 forward, then #59 on the other side, then . . ." After a while of this he couldn't walk at all.

Yehudi Menuhin, one of the greatest prodigies and virtuosos ever, after forty years or so of performing decided to analyze his technique. After a long period of study and analysis and revision, he suddenly found he could hardly play properly any more. He then had to undo the damage he had done by trying to apply precisely the approach advocated by Berg.

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by guitarrista » Sat Nov 18, 2017 6:42 pm

The main idea of this essay about latency is useful in general, especially if one does not know that there is roughly 100ms latency between the brain giving a command and the muscles contracting to execute it. Also useful is the discussion of the consequence of that in terms of playing at fast tempi which necessitates executing "motor programs" - i.e. a set of motions without getting sensor feedback for each individual motion as there is no time for the feedback to arrive and influence the next motion in the set - and then the discussion about chunking.

However, I think Berg makes a crucial logical error when he equates the prescription in traditional methods to not move a finger until the last possible instant with not giving a command to move the finger until the last instant". This precipitates his entire critique of the recipes in traditional methods which is the bulk of the essay.

And yet there is no inconsistency in the teaching methods at least as he quotes from them - not lifting the finger to move until the last possible instant DOES NOT MEAN waiting to think about moving the finger until that instance - instead the thinking of moving comes about 100ms before that; all one has to do with a student is emphasize that distinction to prevent misinterpretation.

In fact, you can easily find videos of concert level guitarists thinking about the move before it happens - focus on the face and eyes of the guitarists before any positional shifts happen - notice how s/he glances at the new position a bit before the move is initiated - that is the external clue for us of them thinking about the move a bit before it actually happens. Watch how consistently this happens (they do not have to glance in order to think about the move, so not glancing in advance does not mean they are not thinking in advance - however it just so happens that it is a consistent "tell" that we the audience can observe).

BTW, this latency is the reason behind calling for a false start at track events when someone starts moving in a time less then 0.1s from the moment the gun fired (0.1 s = 100ms). Athletics has accepted that 100ms cutoff and are assuming that anyone reacting faster than that is not really reacting to the gun but to their own timing trying to get an unfair advantage.
Last edited by guitarrista on Sun Nov 19, 2017 9:33 pm, edited 2 times in total.
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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by Ramon Amira » Sat Nov 18, 2017 7:36 pm

guitarrista wrote:
Sat Nov 18, 2017 6:42 pm
The main idea of this essay about latency is useful in general, especially if one does not know that there is roughly 100ms latency between giving a command to the brain and the muscles contracting to execute it.
This idea might be interesting, but I don't see how it is useful. Does anyone suppose that while a musician is actually playing he is going to think about or calculate latency? In milliseconds no less. There simply is no practical application of all this information.

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by Jack Douglas » Sat Nov 18, 2017 8:38 pm

I’m not a professional musician but I did take a speed reading course many years ago and his premise about speed in many ways is like the speed reading course I took and makes a lot of sense. The speed reading method I used was one in which by exercises eliminated speaking a word as it was read and only looking at a word. The concept was that silently speaking a word takes far longer than the eye and mind can recognize a word. So the practice routine included flipping pages very fast trained the eyes and mind to recognize a word without repeating it to oneself. Night after night I practiced with children’s books and one evening it came together. I picked up a new action/thriller I had just bought and used it to do my page flipping practice and then proceeded to speed read the entire book in time it took to flip the pages as fast as I could.
So, I suspect the technical aspect of speed reading can be utilized by musicians to play fluently at very fast speeds, but will require the elimination of solfegging or other silent speaking of individual notes.
Since I am strictly a hobbyist This May be way off base, but I see a connection.
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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by Ramon Amira » Sat Nov 18, 2017 10:11 pm

Not analogous.

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by Jack Douglas » Sun Nov 19, 2017 12:06 am

Ramon Amira wrote:
Sat Nov 18, 2017 10:11 pm
Not analogous.

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Why?
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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by Rasputin » Sun Nov 19, 2017 1:25 pm

Ramon Amira wrote:
Sat Nov 18, 2017 7:36 pm
guitarrista wrote:
Sat Nov 18, 2017 6:42 pm
The main idea of this essay about latency is useful in general, especially if one does not know that there is roughly 100ms latency between giving a command to the brain and the muscles contracting to execute it.
This idea might be interesting, but I don't see how it is useful. Does anyone suppose that while a musician is actually playing he is going to think about or calculate latency? In milliseconds no less. There simply is no practical application of all this information.

Ramon
I think the problem goes deeper than that. I was reminded of an experiment by W. Grey Walter I had read about - here is Dan Dennett's account of it:

"Grey Walter performed his experiment with patients in whose motor cortex he had implanted electrodes. He wanted to test the hypothesis that certain bursts of recorded activity were the initiators of intentional actions. So he arranged for each patient to look at slides from a carousel projector. The patient could advance the carousel at will, by pressing the button on the controller. (... this was a free decision, timed only by an endogenous rise in boredom, or curiosity about the next slide, or distraction, or whatever.) Unbeknownst to the patient, however, the controller button was a dummy, not attached to the slide projector at all! What actually advanced the slides was the amplified signal from the electrode implanted in the patient's motor cortex.

One might suppose that the patients would notice nothing out of the ordinary, but in fact they were startled by the effect, because it seemed to them as if the slide projector was anticipating their decisions. They reported that just as they were "about to" push the button, but before they had actually decided to do so, the projector would advance the slide - and they would find themselves pressing the button with the worry that it was going to advance the slide twice!"

There may be differences between that situation and ours, but it is not safe to assume that the command to move the fingers is really given when we think it is, or that the latency runs from that time.
guitarrista wrote:
Sat Nov 18, 2017 6:42 pm
... I think Berg makes a crucial logical error when he equates the prescription in traditional methods to not move a finger until the last possible instant with not giving a command to move the finger until the last instant". This precipitates his entire critique of the recipes in traditional methods which is the bulk of the essay.

And yet there is no inconsistency in the teaching methods at least as he quotes from them - not lifting the finger to move until the last possible instant DOES NOT MEAN waiting to think about moving the finger until that instance - instead the thinking of moving comes about 100ms before that; all one has to do with a student is emphasize that distinction to prevent misinterpretation.
Grey Walter's findings suggest that our perception of when commands are given is already calibrated for that, in which case this approach would be adjusting for the same thing twice. In other words it could be that we already perceive the command to be given at the exact moment of execution, as Berg assumes, even if the motor control program has actually been initiated before that. I'm also thinking that there there's quite a long series of processes here, and we have to be careful about what latency we are talking about. Each process is obviously going to take some time, so it does depend on what we consider to be the start and end points. I am not sure how analogous the starting gun example is, because that is not the same series - the trigger is external and has to be processed before we even get to the initiation of the motor program - so if that latency is 100ms, the latency we are concerned with may well be less.

In general I think we live in the middle of a chain of command with subsystems working away in the dark above and below us. I think our movements are likely to be most skilful when we stay where nature has put us and don't try to take over jobs which those subsystems are specialised to do.

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by guitarrista » Sun Nov 19, 2017 6:37 pm

Rasputin wrote:
Sun Nov 19, 2017 1:25 pm
I am not sure how analogous the starting gun example is, because that is not the same series - the trigger is external and has to be processed before we even get to the initiation of the motor program - so if that latency is 100ms, the latency we are concerned with may well be less.
It is the same concept of latency, but the number value of 100ms is just a coincidence.

First, that 100ms or 200ms that Berg quotes is some average value; there is variability around it as well as differences in values between older and newer studies; I've seen more recent studies summarized as 40-100ms latency (for the brain signal-to-muscle-twitch part).

Second, the athletics number aims to address the minimum as a threshold rather than represent the average.

Third, the athletics number incorporates the time for receiving and processing the signal as a sound, as you point out.

Air pressure waves travel time (assume about 1 metre between the loudspeaker right behind the athlete and his/her head) is about 30 ms. This part is the same for all athletes on the track. Processing the air pressure fluctuations as sound in the brain takes on average about 30 ms also (20-50). This leaves about 40 ms as the brain-to-muscle activation latency which is the minimum recorded latency. Therefore anyone showing a reaction time of less than 100ms is assumed to be reacting not to the gun but to their own timing.
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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by Rasputin » Sun Nov 19, 2017 7:24 pm

guitarrista wrote:
Sun Nov 19, 2017 6:37 pm
Air pressure waves travel time (assume about 1 metre between the loudspeaker right behind the athlete and his/her head) is about 30 ms. This part is the same for all athletes on the track. Processing the air pressure fluctuations as sound in the brain takes on average about 30 ms also (20-50). This leaves about 40 ms as the brain-to-muscle activation latency which is the minimum recorded latency. Therefore anyone showing a reaction time of less than 100ms is assumed to be reacting not to the gun but to their own timing.
Makes sense - thanks for the clarification. So the figure we are mainly concerned with is somewhere between 40ms and 200ms, representing the chain from brain signal to muscle activation, and it seems that the command is perceived to be given at some point during that window, but we don't know when. I think I'm with Ramon in thinking that this is interesting but not of much direct help in terms of getting better.

The one thought I had is that it might give us some guidance on what to practise as a gesture and what to practise as individual movements. I've posted elsewhere that I'm not convinced you are practising tremolo until you reach a speed where pima (or whatever you are using) is a single gesture rather than individual finger movements. I thought perhaps the threshold was reached when ma / am becomes a compound stroke, but it occurs to me reading this thread that it could be do with chunking. I don't suppose that the 40-200ms figure is the relevant one, because the chunking threshold is the speed at which you have to send the next signal out before you've received feedback from the last one - so presumably we would need to double the figure. If you think that the impression we are looking to create with tremolo starts when there is about 125ms between notes and realistically goes up to maybe 80ms between, there may be some people out there who can do it as individual movements, and for them the start slow and gradually speed up approach may work.

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by guitarrista » Mon Nov 20, 2017 7:14 pm

Rasputin wrote:
Sun Nov 19, 2017 7:24 pm
The one thought I had is that it might give us some guidance on what to practise as a gesture and what to practise as individual movements. I've posted elsewhere that I'm not convinced you are practising tremolo until you reach a speed where pima (or whatever you are using) is a single gesture rather than individual finger movements. I thought perhaps the threshold was reached when ma / am becomes a compound stroke, but it occurs to me reading this thread that it could be do with chunking. I don't suppose that the 40-200ms figure is the relevant one, because the chunking threshold is the speed at which you have to send the next signal out before you've received feedback from the last one - so presumably we would need to double the figure. If you think that the impression we are looking to create with tremolo starts when there is about 125ms between notes and realistically goes up to maybe 80ms between, there may be some people out there who can do it as individual movements, and for them the start slow and gradually speed up approach may work.
I few more thoughts on this.

I personally dislike using the single gesture/compound [single] stroke terminology because I see it as potentially confusing matters. What that is referring to is conscious versus subconscious control; however when we execute a series of movements subconsciously they are still individual (i.e. not synchronous but separated in time) movements, just not individual conscious movements.

The conscious-subconscious control and chunking discussion would be more interesting and potentially fruitful for students. The latency bit is only peripherally related. BTW I am not sure we can say sending the next signal after getting feedback necessitates doubling the 40-200ms figure - feedback would not travel back the same way. Visual or auditory feedback would take as little as 15-25ms. Tactile probably more however it would have started as soon as the fingertip touches the string which is before the sound is created.

What does that imply for studying tremolo? I think slow perfect practice in order to enable chunking ami, and pami evenness, then brief fast(er) playing of a few pami cycles to test-drive chunking but also to condition fast movements. The slow bit of practice will happen at faster tempos with time naturally because of skill internalization and amalgamation; this implies the forced gradual ramp-up with a metronome is less useful as a study technique than it may seem.
Last edited by guitarrista on Mon Nov 20, 2017 11:20 pm, edited 1 time in total.
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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by mainterm » Mon Nov 20, 2017 10:12 pm

Jack Douglas wrote:
Sun Nov 19, 2017 12:06 am
Ramon Amira wrote:
Sat Nov 18, 2017 10:11 pm
Not analogous.

Ramon
Why?
because you play guitar with your fingers, not your eyes. this fact significantly weakens the relatedness of speed reading techniques. maybe you can dial in a stronger connection vis-a-vis sight reading or score reading generally.

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by Rasputin » Mon Nov 20, 2017 10:15 pm

guitarrista wrote:
Mon Nov 20, 2017 7:14 pm
I personally dislike using the single gesture/compound [single] stroke terminology because I see it as potentially confusing matters. What that is referring to is conscious versus subconscious control; however when we execute a series of movements subconsciously they are still individual (i.e. not synchronous but separated in time) movements, just not individual conscious movements.
Yes, the distinction exists at the level of unconscious initiation of the motor program, and at the level of conscious command, but not usually at the level of the muscles. We live at the level of conscious command, so I still think there is a place for it - we just have to remember that at some point in the chain, it is broken down into individual tasks.

If the compound ma stroke is due to mechanical interdependence between those fingers, rather than any latency issue, then it seems to be a case of the movement being compound even at muscular level. It's probably more complex than that, because a controlled compound ma stroke may involve holding a back a bit, but in principle I think there is such a thing as a compound movement at muscular level.

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by mainterm » Mon Nov 20, 2017 10:16 pm

I'm trying to picture myself saying to a student:

"I see you are hitting a fluency barrier, so let's start talking about how to transcend latency"

I'm sure there's a student out there that needs this nomenclature to succeed as a learner, but I haven't heard of or met them :)

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Re: Blog post by Christopher Berg on "Virtuosity Unveiled"

Post by guitarrista » Tue Nov 21, 2017 4:48 pm

Rasputin wrote:
Mon Nov 20, 2017 10:15 pm
guitarrista wrote:
Mon Nov 20, 2017 7:14 pm
I personally dislike using the single gesture/compound [single] stroke terminology because I see it as potentially confusing matters. What that is referring to is conscious versus subconscious control; however when we execute a series of movements subconsciously they are still individual (i.e. not synchronous but separated in time) movements, just not individual conscious movements.
Yes, the distinction exists at the level of unconscious initiation of the motor program, and at the level of conscious command, but not usually at the level of the muscles. We live at the level of conscious command, so I still think there is a place for it - we just have to remember that at some point in the chain, it is broken down into individual tasks.
I think where we differ is when you say "not usually at the level of the muscles". The motor program is still a series of separate commands driving separate muscles or muscle bundles in some memorized and internalized sequence; hence I don't like it being called a single gesture or stroke. As an easy example, consider fast i-m alternation at tempo 150x4 or faster. Even if you are convinced that the flexor muscle activation is the same command for both i and m (I don't since we have individual control over these fingers, but let's skip over that), there is an alternation of flexor, extensor, flexor, extensor for each i-m-i-m set, done subconsciously at that speed. ("Passive return" is not fast enough to accomplish the finger reset for its next stroke at that speed). Or perhaps I've misinterpreted your view on this.
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