beau's blog

Recently I’ve gotten pretty interested in some of Brian Ferneyhough’s ideas about music, especially what he has to say about his use of rhythm, duration and time. I have misgivings about a lot of his work, but I’ve become fond of Bone Alphabet, a piece for seven percussion instruments of indeterminate sound where adjacent instruments must not be of the same family. There’s an article by Steven Schick about the process of learning Bone Alphabet, which took him a maybe-not-totally-justifiable nine months. To get it right he cut up the score and pasted it on to graph paper so he could see the rhythms more clearly, did quite a bit of math to understand the polyrhythms, memorized stickings measure by measure, and other such feats of dedication and devotion. The result was, interestingly, a feeling of being deeply situated within his body. He talks quite a bit about the importance of bodily movement to the piece, mentioning at one point that an audio recording alone would not really convey the work. Here’s a good excerpt (Schick 1994):

My method of actually learning the piece involved first cutting out each bar and gluing it on graph paper so that I could better calculate rhythmical relationships. Then I made all decisions regarding sticking and mallet choice and memorized them before going on to the next measure. The advantage to this approach was that, by memorizing as the first and not the last step in the process, I could more quickly embed the material I was learning in the realm of physical gesture. As a result, from the first instant the piece became a theatrical arena where physical gesture was not the simple by-product of performance, but an integral part of a growing interpretive point of view. The instrument became a kind of stage for the enactment of, in Ferneyhough’s words, “a theatre of the body.”

Ross Karre has recorded his interpretation of Bone Alphabet and put it on YouTube. Unfortunately embedding is disabled, so to view it you’ll have to follow these links:

• Bone Alphabet by Brian Ferneyhough 1/2
• Bone Alphabet by Brian Ferneyhough 2/2

And, finally, a couple of quotes from Ferneyhough to round this all out. From his essay Duration and rhythm as compositional resources:

Whilst the impulse-structure and its audibility are clearly variably perceptible in concrete compositional situations, I maintain that enough of a correspondence is maintained in the middle to long term to enable the flow of space/density ratios demonstrated capable of carrying the main weight of formal organization. According to this principle, degrees of compression, distortion, convergence or mutual interference are calculable in respect of the degree to which the sense of clock time is supported or subverted by the specific tactility of impulse density setting the ‘inner clock’ of a particular metric space.

—

As always in the discussion of matters artistic, it is not the clear-cut cases which prove most pertinent, but the ill-defined and fluctuating ‘grey zones’ where a given rhythmic phenomenon may be called on to assume multiple functional roles.

References:

• Schick, S. (1994) Developing an Interpretive Context: Learning Brian Ferneyhough’s Bone Alphabet. Perspectives of New Music, Vol. 32, No. 1: 132-153
• Ferneyhough, B. “Duration and rhythm as compositional resources.” Collected Writings Eds. Boros, J.; Toop, R. Harwood Academic Publishers, 1995.

I’ve come to the mind-reading issue at an interesting time. Recently, Nikos Logothetis published an article called What we can do and what we cannot do with fMRI. It’s a fascinating paper, and numerous blogs picked up on it. The best summary comes from Mind Hacks and is ominously entitled The great fMRI smackdown cometh.

About the application of pattern-classification techniques (e.g. MVPA) to fMRI data, Logothetis says the following:

In humans, fMRI is used routinely not just to study sensory processing or control of action, but also to draw provocative conclusions about the neural mechanisms of cognitive capacities, ranging from recognition and memory to pondering ethical dilemmas. Its popular fascination is reflected in countless articles in the press speculating on potential applications, and seeming to indicate that with fMRI we can read minds better than direct tests of behaviour itself. Unsurprisingly, criticism has been just as vigorous, both among scientists and the public. In fact, fMRI is not and will never be a mind reader, as some of the proponents of decoding-based methods suggest, nor is it a worthless and non-informative ‘neophrenology’ that is condemned to fail, as has been occasionally argued.

A lot of this has to do with how one defines “mind-reading,” and whether or not what’s being read is low-level (e.g. the orientation of a visual stimulus) or high level (e.g. the presence of a mental state). There are numerous examples of papers which exploit fMRI data to erroneously support what I would call very high-level conclusions about human behavior, such as whether or not subjects have anxiety regarding Mitt Romney. (This and many other such studies are handily refuted by The Neurocritic, who also had some interesting commentary on Logothetis’s paper.) However, I think the study by Kay et al. on the identification of novel, real-world images suggests that, at lest for low-level, sensory information, fMRI might be quite the mind-reader indeed. There’s a good editorial in Science by Greg Miller which has, I think, a pretty balanced view of things, resorting to neither abject pessimism nor fanciful speculation.

The risk I think Logothetis and others are pointing out is that inferring a mental state from brain imaging data puts one on pretty shakey ground. I think this is especially true for studies which don’t take into account distributed patterns of brain activation, but even pattern-classification based studies need to be very careful about making the leap to state attribution. Just because we can say, in a sense, that there is a hierarchy inside a rhesus macaque’s brain that differentiates between cats and dogs, we can’t necessarily say that the monkey knows what a dog is and that it has a degree of similarity to a cat equal to X. It’s possible that the observed hierarchical organization might be completely unconscious.

Logothetis gets specific about his reservations regarding pattern classification techniques:

Such multivariate analyses or pattern-classification-based techniques (decoding techniques) can often detect small differences between two task or stimulus conditions—differences that are not picked up by conventional univariate methods. However, this is not equivalent to saying that they unequivocally reveal the neural mechanisms underlying the activation patterns.

And he’s right. But the strength of pattern classification of fMRI data is not that it can reveal underlying neural mechanisms, nor that it can simply detect small differences between patterns of activation (cheating past the spatial resolution limit, basically), but that it allows us to evaluate the similarity of patterns of activiation based on a variety of arbitrary criterea. It’s not cool because it gets us closer to some underlying machinery, it’s cool because it lets us talk about similarity and difference of patterns of activation in a quantitative way. This has surprising power.

References:

• Logothetis, N.K. (2008) What we can do and what we cannot do with fMRI. Nature 453:869-78.
• Kay, K.N.; Naselaris, T; Prenger, R.J.; Gallant, J.L. (2008) Identifying natural images from human brain activity. Nature 452: 352-356.

A fantastic YouTube video has been making the rounds. It’s a cockatoo named Snowball dancing to The Backstreet Boys. It’s all kinds of awesome, but it’s also one of, if not the first, totally conclusive demonstration of an animal enthusiastically entraining its movements to rhythmic sound. Here’s the bird:

Aniruddh Patel got on the case, did some experiments and wrote a paper on the cockatoo. He concludes that, while it’s confined to a relatively small range of tempos and isn’t particularly reliable, the dancing bird is basically for real. The paper is a great read. Its final sentence is oddly touching:

It will be interesting to determine whether the range of tempi to which Snowball can synchronize is expanded when dancing with a partner.

Here’s the paper:

• Patel, A.D., Iversen, J.R., Bregman, M.B., Schulz, I., & Schulz, C. (in press). Investigating the human-specificity of synchronization to music. In: Proceedings of the 10th International Conference on Music Perception & Cognition (ICMPC10), August 2008, Sapporo, Japan. M. Adachi et al. (Eds.), Adelaide: Causal Productions.

More videos on Patel’s publications page.