Washington, DC  3.16.9

Sounds sometimes behave so strangely....

As William Butler Yeats once asked, 

Thanks to alert reader (and rock star and Pnosis's website designer) Knox Bronson, now we have the answer to a cognate question:

How can we know the difference between the spoken and sung word?

Turns out, we cannot.

A paper entitled the Speech-to-Song Illusion by Deutsch, Lapidis and Henthorn, of the Department of Psychology of the University of California, San Diego presented at the 156th Meeting of the Acoustical Society of America:

reports the first formal investigation of a striking illusion: A spoken phrase is made to be heard convincingly as sung rather than spoken, and this perceptual transformation occurs without altering the signal in any way, or adding any musical context, but simply by repeating the phrase several times over. The illusion is surprising, as it is generally assumed that whether we perceive a phrase as spoken or as sung depends on the physical characteristics of the sound.

The phrase occurs in a sentence in the opening commentary of the compact disc Musical Illusions and Paradoxes (Diana Deutsch, 1995). When you listen to this sentence in the normal way, it appears clearly to be spoken – as indeed it is. Yet when you play a phrase that’s embedded in it several times over, a curious effect emerges: At some point, instead of appearing to be spoken, the phrase appears to be sung.

Now here again is the exact same sentence as you just heard . You will probably find that it begins by sounding as speech, just as before. But when you come to the phrase that had been repeated, it suddenly appears to burst into song.

LISTEN: Sound Demo 2.

An extraordinary, and even hypnotic, rendition of the power, or perhaps powerlessness, of the human mind:

And here are the reproductions of all 11 subjects, digitally mixed together so that they are played as a chorus. (A small amount of reverberation has been added, but otherwise the sounds are exactly as they were recorded.)

LISTEN: Sound Demo 4.

Brava, Professors Deutsch and company!