Tag Archives: pitch

Quick Review: How Music Works

Posted on by

I like reading about music so I recently thought I would take a chance with a recently published book by British physicist John Powell: How Music Works: The Science and Psychology of Beautiful Sounds, From Beethoven to the Beatles. A few thoughts about this text which is intended for a general audience:

1. One of the key things this text tries to do is explain why we have the music structure today that we do. So he includes explanations about musical modes that developed in history (of which we use two today, one the major scale and one the minor scale) and how instruments, like the harp, can be configured to produce notes.

2. One of the most interesting things to me in this book was the fact that agreement about modern notes didn’t happen until a conference in 1939. Before that, an A in Leipzig and an A in Paris might not be the same sound. It wasn’t until this conference that a particular frequency (A = 440) was set so that all instruments could be set to the same pitches. And even then, Powell suggests choosing this particular frequency occurred not because it is a better sound but rather because it is somewhere in the middle and seemed good. To think that the sounds we know today are really a social construction is intriguing.

3. There are number of little discussions that a reader might find interesting about perfect pitch, the physics of sound versus noise, how we can rate sound intensity (and he does not like the decibel system), and whether there are certain keys that are happier or sadder (the conclusion: no, they all share the same patterns of notes).

4. While I enjoyed a number of these shorter discussions, I wonder whether someone with limited or no musical knowledge could take much from this book. At various points, Powell suggests one doesn’t need to know how to play or read music to understand the discussions but I think it would be difficult. To his credit, Powell does suggest that anyone of any age can learn music – yes, it takes time (and he invokes Gladwell’s rule of 10,000 hours needed for expertise) but he suggests the idea that some people are musical and others are not does not hold water.

Overall, a book with some interesting points. The discussion bogs down in places and may be difficult for those with little music knowledge but it is an interesting start in considering how music is made.

The curveball as optical illusion

Posted on by

It is amazing to me the amount of stories I’ve seen over the years about how the curveball works. According to new research, the “break” the batter sees may just all be an optical illusion:

Yet as the ball nears home plate, the batter observes a sudden jump in its trajectory, the notorious “break.” A new study in PLoS ONE argues that the discrepancy between the physics and the perception of the curveball may be all in the mind — or, more specifically, an optical illusion created by the batter’s eyes and brain.

The human visual system dedicates more of its resources to processing images in the center of our field of view than in our peripheral vision. Larger numbers of photoreceptors and retinal ganglion cells in the fovea — the center part of our eyes — help produce extremely high-res, three-dimensional static images. And as the images processed by our retinas head to the brain, larger numbers of neurons in the visual processing centers (lateral geniculate nucleus and primary visual cortex) are responsible for helping make sense of what we see when looking at something straight on as compared to out of the corner of our eye.

During a very small pilot study, Arthur Shapiro’s team created a computer simulation to determine how the motion of a curveball could create an optical illusion as it skates across our entire visual field. If the observers tracked a spinning gray disc while directly looking at the falling object, it moved as intended. But if people tracked the spinning disc out of the corner of their eye — in their peripheral vision — discs that dropped straight down appeared to fall at an angle, while discs that followed a smooth arc as they descended seemed to plunge straight down.

Fascinating. So how do baseball players hit a curveball – are they able to compensate for this optical illusion and still swing in the right place? Also, could there be players who are less affected by this optical illusion, thus explaining why some are better fastball vs. curveball hitters?