More than meets the ear in successful cocktail party conversations

March 5, 2008

Just picture the scene: you’re at a cocktail party, talking to someone you would like to get to know better but the background noise is making it hard to concentrate. Luckily, humans are very gifted at listening to someone speaking while many other people are talking loudly at the same time. This so-called cocktail-party-phenomenon is based on the ability of the human auditory system to decompose the acoustic world into discrete objects of perception.

It was originally believed that the major acoustic cue used by the auditory system to solve this task was directional information of the sound source, but even though localisation of different sound sources with two ears improves the performance, it can be achieved monaurally, for example in telephone conversations, where no directional information is available.

Scientists led by Holger Schulze at the Leibniz-Institute for Neurobiology in Magdeburg, and the Universities of Ulm, Newcastle and Erlangen have now found a neuronal mechanism in the auditory system that is able to solve the task based on the analysis of the temporal fine structure of the acoustic scene. The findings, published in this week’s PLoS ONE, show that different speakers have different temporal fine structure in their voiced speech and that such signals are represented in different areas of the auditory cortex according to this different time structure.

By means of a so-called winner-take-all algorithm, one of these representations gains control over all other representations. This means that only the voice of the speaker to whom you wish to listen is still represented in the auditory cortex and can thus be followed over time. This predominance of the representation of one speaker’s voice over the representations of all other speakers is achieved by long-range inhibitory interactions that are first described by Schulze and colleagues using functional neurophysiological, pharmacological and anatomical methods.

The findings provide a deeper understanding of how the parcellation of sensory input into perceptually distinct objects is realised in the brain, and may help to improve the auditory experience of hearing aid wearers at cocktail parties.

Citation: Kurt S, Deutscher A, Crook JM, Ohl FW, Budinger E, et al (2008) Auditory Cortical Contrast Enhancing by Global Winner-Take-All Inhibitory Interactions. PLoS ONE 3(3): e1735. doi:10.1371/journal.pone.0001735 (www.plosone.org/doi/pone.0001735)

Source: Public Library of Science

Explore further: Researchers discover hidden brain pathways crucial to communication

Related Stories

Researchers discover a biological marker of dyslexia

February 19, 2013

(Medical Xpress)—Though learning to read proceeds smoothly for most children, as many as one in 10 is estimated to suffer from dyslexia, a constellation of impairments unrelated to intelligence, hearing or vision that make ...

Why can’t I learn a new language?

July 8, 2008

Adults, even the brightest ones, often struggle with learning new languages. Dr Nina Kazanina in the Department of Psychology at the University of Bristol explains why.

Taking up music so you can hear

August 17, 2009

Anyone with an MP3 device -- just about every man, woman and child on the planet today, it seems -- has a notion of the majesty of music, of the primal place it holds in the human imagination.

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. ...

Cow embryos reveal new type of chromosome chimera

May 27, 2016

I've often wondered what happens between the time an egg is fertilized and the time the ball of cells that it becomes nestles into the uterine lining. It's a period that we know very little about, a black box of developmental ...

Shaving time to test antidotes for nerve agents

February 29, 2016

Imagine you wanted to know how much energy it took to bike up a mountain, but couldn't finish the ride to the peak yourself. So, to get the total energy required, you and a team of friends strap energy meters to your bikes ...

0 comments

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.