Friday, 27 January 2017

A Tale of Two Sight-Readers



Aria is 10 years old, and has been studying piano with me for many years. She’s small for her age, with a shy, soft voice and a wry sense of humour. At her lesson, I test her note-naming and find it, to be perfectly frank, abysmal. We continue on with the lesson, and start work on a new piece, Beethoven’s Ecossaise in G Major. I ask her to sight-read the right hand part, and she peers at the music, figuring out what the first note is. Then she plays through the first line of music fairly well, doing an excellent job considering her terrible performance at note-naming. However, in the second bar, there is an interval of a seventh. She misreads the second note of the interval, ending up playing the end of the phrase a step too low.

Despite not knowing her notes very well, Aria is a half-decent sight-reader because she mostly reads by interval, simply going up or down one note (a step) or two (a skip) as the music indicates. Larger intervals are harder to read, so she sometimes makes mistakes with these, and reading over a line break is much more difficult because it’s hard to see the vertical relationship between the notes when they are on different lines.

Leonard, 9 years old, arrives for his lesson with a cheerful smile. He has been learning The Silent Moon by Nancy Telfer, but when he plays it for me, he quickly runs into trouble, hitting a wrong note in the second phrase. He can hear it too, and restarts the phrase, this time landing on a different wrong note in the same place. I notice that Leonard is not looking at the music; he is watching his fingers. Despite the fact that the music book is open on front of him, he is playing from memory, searching for the notes by ear. I’m concerned about his ability to read the music, so I test his note-naming using stack of flashcards. Leonard names the notes quickly and easily, so I open up his sight-reading book to a simple exercise. Before he plays it, I ask him to look at the music and tell me how many times the melody moves by a skip instead of step. He puzzles through the music and incorrectly tells me there are three skips in the melody. In fact, there is only one.

These two students use entirely different strategies for reading music. Leonard does well at reading by note, while Aria’s strength is reading by interval. Strong sight-readers combine the two strategies. What you might not realize is that the two different strategies use entirely different parts of the brain.

When we read music, the visual information travels from the eyes to the visual cortex at the very back of the brain. The visual cortex receives that information and then passes it on to other regions of the visual cortex that process that information, sorting out contours of the things we see, how they’re oriented in space, if they’re moving, what colour they are, and how bright. The brain needs to do two main things with all this information: It has to answer the question “what am I seeing?” and it has to answer the question “what should I do with what I’m seeing?”

To answer these two questions, visual information is processed through two very different pathways in the brain, known as the ventral stream (vision for perception) and the dorsal stream (vision for action). 

Dorsal stream (red arrow) and ventral stream (blue arrow) of visual processing. Image courtesy of "BodyParts3D, © The Database Center for Life Science licensed under CC Attribution-Share Alike 2.1 Japan."


The ventral stream, which involves the temporal lobe of the brain, has long been known as the “what” stream, since it is the pathway we use to recognize and name the things we are seeing. It is this pathway that we use for note-naming. Imagine we see a note on the first space of the treble staff. In the ventral stream, what we see match up the image of what we see with pictures we have stored in memory, and this is how we know to name that note as a F. This is how we recognize what we see, leading to a conscious perception of what we are looking at, and a conscious understanding of what we see. In music reading, we use the ventral stream for note-naming, recognizing musical symbols and understanding their meaning, for conscious pattern recognition, and for naming chords.

It’s this ventral stream that is a weakness in Aria’s sight-reading. She has a hard time naming individual notes, so finding the correct note to play at the beginning of a line or after a large interval is difficult. Leonard, on the other hand, has a strong ventral stream, but on its own it is not enough to make him a good sight-reader. He also needs to have a strong dorsal stream.

The dorsal stream, which involves the parietal lobe, directly relates what we see to the actions that are required. The parietal lobe plays an important role in spatial perception, and so this pathway processes the spatial aspects of what we’re looking at, and matches it up with our knowledge of what to do with that object. This activates the correct movement. In music reading, we use the dorsal stream to know what movements to make to play straight-forward patterns, to know how far to reach for each interval, to make the correct hand shapes for chords. The dorsal stream automatically converts well-known visual cues into movements.

This is why Aria, who is terrible at note-naming, can sight-read music pretty well. Her dorsal stream does a good job of reading intervals and telling her what finger movements she should make. Leonard, on the other hand, tries to rely on his ventral stream for reading music. He can name the notes well, but he doesn’t easily translate the written notes into how he should move his fingers.

How do I help these two students? It’s not enough to just hand them a sight-reading book and tell them to go practice. Aria needs to practice note-naming specifically:  matching up notes on the staff with their names. In addition, she should practice playing individual notes on the piano. Flashcards are a good tool here. Leonard has different needs:  he should practice reading intervallically. An excellent resource for this is The Sight Reading Drill Book by Barbara Siemens, which systematically introduces intervals and chord patterns, and encourages the student to read by interval and by hand shape rather than by note-naming, strengthening the dorsal stream of visual processing. Siemens describes this approach by saying, “It’s a mind-finger thing. I think sometimes you have to try to bypass that naming thing and just do it intuitively. Which means you have to drill it enough.” As an experienced piano teacher, Siemens saw a need in her own students for intervallic sight-reading practice. “Because you don’t have time to think of notes as you’re going.  The name thing is just attaching a tag to something that should go intuitively.”

Every student has different strengths and weaknesses. This is true even within a single skill such as sight-reading. As a teacher, it’s important that I remember that and use different approaches to bolster students’ abilities and help them achieve their musical goals.

References

Goodale, M.A. (2011). Transforming vision into action. Vision Res. 51, 1567–1587.

Goodale, M.A. (2013). Separate visual systems for perception and action: a framework for understanding cortical visual impairment. Developmental Medicine & Child Neurology 55, 9–12.

Goodale, M.A., and Milner, A.D. (1992). Separate visual pathways for perception and action. Trends in Neurosciences 15, 20–25.

Ungerleider, L.G., and Mishkin, M. (1982). Two Cortical Visual Systems. In Analysis of Visual Behaviour, (Cambridge, Mass.: MIT Press), pp. 549–586.

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