Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.

Wednesday, July 24, 2019

Meaning in music

As someone fascinated by neuroscience, language, and music, you can imagine how excited I was to find some new research that combined all three.

A link sent to me by a loyal reader of Skeptophilia describes a study that is the subject of a paper in Nature Neuroscience last week with the rather intimidating title "Divergence in the Functional Organization of Human and Macaque Auditory Cortex Revealed by fMRI Responses to Harmonic Tones."  Written by Sam V. Norman-Haignere (Columbia University), Nancy Kanwisher (MIT), Josh H. McDermott (MIT), and Bevil R. Conway (National Institute of Health), the paper shows evidence that even our close primate relatives don't have the capacity for discriminating harmonic tones that humans have -- that our perception of music may well be a uniquely human capacity.

"We found that a certain region of our brains has a stronger preference for sounds with pitch than macaque monkey brains," said Bevil Conway, senior author of the study.  "The results raise the possibility that these sounds, which are embedded in speech and music, may have shaped the basic organization of the human brain."

Monkeys, apparently, respond equally to atonal/aharmonic sounds, while humans have a specific neural module that lights up on an fMRI scan when the sounds they hear are tonal in nature.  "These results suggest the macaque monkey may experience music and other sounds differently," Conway said.  "In contrast, the macaque's experience of the visual world is probably very similar to our own.  It makes one wonder what kind of sounds our evolutionary ancestors experienced."

[Image is in the Public Domain]

It immediately put me in mind of tonal languages (such as Thai and Chinese) where the same syllable spoken with a rising, falling, or steady tone completely changes its denotative meaning.  Even non-tonal languages (like English) express connotation with tone, such as the rising tone at the end of a question.  And subtleties like stress patterns can substantially change the meaning.  For example, consider the sentence "She told me to give you the money today?"  Now, read it aloud while stressing the words as follows:
  • SHE told me to give you the money today?
  • She TOLD me to give you the money today?
  • She told ME to give you the money today?
  • She told me to GIVE you the money today?
  • She told me to give YOU the money today?
  • She told me to give you the MONEY today?
  • She told me to give you the money TODAY?
No two of these connote the same idea, do they?

I'm reminded of how the brilliant neuroscientist David Eagleman describes the concept of the umwelt of an organism:
In 1909, the biologist Jakob von Uexküll introduced the concept of the umwelt.  He wanted a word to express a simple (but often overlooked) observation: different animals in the same ecosystem pick up on different environmental signals.  In the blind and deaf world of the tick, the important signals are temperature and the odor of butyric acid. For the black ghost knifefish, it's electrical fields.  For the echolocating bat, it's air-compression waves.  The small subset of the world that an animal is able to detect is its umwelt... 
The interesting part is that each organism presumably assumes its umwelt to be the entire objective reality "out there."  Why would any of us stop to think that there is more beyond what we can sense?
So tone, apparently, is part of the human umwelt, but not that of macaques (and probably other primate species).  Perhaps other animals include tone in their umwelt, but that point is uncertain.  I'd guess that these would include many bird species, which communicate using (often very complex) songs.  Echolocating cetaceans and bats, maybe.  Other than that, probably not many.

"This finding suggests that speech and music may have fundamentally changed the way our brain processes pitch," Conway said.  "It may also help explain why it has been so hard for scientists to train monkeys to perform auditory tasks that humans find relatively effortless."

I wonder what music sounds like to my dogs?  I get a curious head-tilt when I play the piano or flute, and I once owned a dog who would curl up at my feet while I practiced.  Both my dogs, however, immediately remember other pressing engagements and leave the premises as soon as I take out my bagpipes.

Although most humans do the same thing, so maybe that part's not about tonal perception per se.


The subject of Monday's blog post gave me the idea that this week's Skeptophilia book recommendation should be a classic -- Konrad Lorenz's Man Meets Dog.  This book, written back in 1949, is an analysis of the history and biology of the human/canine relationship, and is a must-read for anyone who owns, or has ever owned, a doggy companion.

Given that it's seventy years old, some of the factual information in Man Meets Dog has been superseded by new research -- especially about the genetic relationships between various dog breeds, and between domestic dogs and other canid species in the wild.  But his behavioral analysis is impeccable, and is written in his typical lucid, humorous style, with plenty of anecdotes that other dog lovers will no doubt relate to.  It's a delightful read!

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]


  1. When I was in college, I helped a friend who studied why frogs and toads responded to certain pitches. Only when you were precise would their behavior be stimulated. I practiced to pitch match, as vocal ear training. The ears of Anuans were a thin membrane with a weight in the middle (like a tuned drum). Six decades on, I'd love to know what's been discovered since.

  2. Oh and in teaching songwriting I used your example of stressing different words to underline meaning with melody and rhythm. Fun stuff.