In Brief: The cocktail party problem

January 4, 2011

People can identify a repeating sound in a noisy room, but only when the noise includes mixtures of distinct distracting sounds, according to a study published this week in the Proceedings of the National Academy of Sciences.

Sound researchers have pondered this so-called "cocktail party problem," which underlies the ability to focus on a specific, unfamiliar sound.

To determine how the parses sound seemingly effortlessly, Josh H. McDermott and colleagues presented listeners with a synthesized audio recording that resembled everyday sounds, such as spoken words and animal .

When the target sound was presented with one other sound, the listeners heard the mixture as a single sound and were unable to identify the target correctly.

However, when the target sound was presented repeatedly, mixed with a distinct distracting sound each time, the listeners developed an impression of the repeating target and identified it in the mixtures.

Further, the listeners' ability to recognize the target sound depended on the number of different mixtures in the audio recording, not the number of times the target was presented.

Hence, the authors suggest, the auditory system detects sounds based on patterns of time and frequency, such as might be produced by feet pounding on pavement or by branches swaying in the wind, and interprets the patterns as sound sources.

Explore further: Brain center for 'sound space' identified

More information: "Recovering sound sources from embedded repetition," by Josh H. McDermott, David Wrobleski, and Andrew J. Oxenham, Proceedings of the National Academy of Sciences, January 2010.

Related Stories

Brain center for 'sound space' identified

September 19, 2007

While the visual regions of the brain have been intensively mapped, many important regions for auditory processing remain terra incognita. Now, researchers have identified the region responsible for a key auditory process—perceiving ...

How does the human brain memorize a sound?

June 3, 2010

Sound repetition allows us to memorize complex sounds in a very quick, effective and durable way. This form of auditory learning, which was evidenced for the first time by French researchers from CNRS, ENS Paris, and Paris ...

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

( -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.