Email Print Share

"Perceptible Difference" -- The Discovery Files

The Discovery Files
Audio Play Audio
The Discovery Files podcast is available through iTunes or you can add the RSS feed to your podcast receiver. You can also access the series via AudioNow® by calling 641-552-8180 on any telephone.


Results of a new study involving macaque monkeys suggest that speech and music might have shaped the human brain's hearing circuits. Using functional magnetic resonance imaging (fMRI), researchers monitored the brain activity of macaques and healthy human volunteers and how it responded to harmonic sounds, or tones. Humans were more sensitive to pitch, a key component of speech and music, than were the macaques.

Credit: NSF/Karson Productions

Audio Transcript:

Do you hear what I hear?

I'm Bob Karson with the Discovery Files, from the National Science Foundation.

You're playing one of your favorite jams for your macaque monkey and he's like, "meh." Before you think he's lost touch, you might wanna check a multi-institution study on macaques' perception of sound and how it's processed in their brains compared to human brains.

To measure brain responses in both, fMRI or functional magnetic resonance imaging was used, to scan for activity in certain areas of the brain as it happens. Various sounds were played two ways: Example a normal macaque call: (Sound effect: sound :03) Then the team digitally removed the tonal qualities of the same sound. (Sound effect: sound :03)

Result: The brains of the humans were much more responsive to the pitch quality of the calls than were the brains of the macaques themselves. Humans showed a stronger preference and sensitivity for sounds with pitch -- the kind of sounds we hear in speech or music -- suggesting those sounds may have shaped the development of the human brain's hearing circuits. The monkeys may see what we see, but they seemingly do not hear what we hear and may experience music and other sounds differently.

Guess that means your macaque won't be complaining that your singing sounds (Sound effect: monkey screech) "pitchy."

"The discovery files" covers projects funded by the government's National Science Foundation. Federally sponsored research -- brought to you, by you! Learn more at nsf.gov or on our podcast.

 
General Restrictions:
Images and other media in the National Science Foundation Multimedia Gallery are available for use in print and electronic material by NSF employees, members of the media, university staff, teachers and the general public. All media in the gallery are intended for personal, educational and nonprofit/non-commercial use only.

Images credited to the National Science Foundation, a federal agency, are in the public domain. The images were created by employees of the United States Government as part of their official duties or prepared by contractors as "works for hire" for NSF. You may freely use NSF-credited images and, at your discretion, credit NSF with a "Courtesy: National Science Foundation" notation. Additional information about general usage can be found in Conditions.

Also Available:
Download the high-resolution JPG version of the image. (66.6 KB)

Use your mouse to right-click (Mac users may need to Ctrl-click) the link above and choose the option that will save the file or target to your computer.

MP3 icon
NSF podcasts are in mp3 format for easy download to desktop and laptops, as well as mobile devices capable of playing them.