The Mudcat Café TM
Thread #104378   Message #2203560
Posted By: Amos
27-Nov-07 - 08:06 PM
Thread Name: BS: Random Traces From All Over
Subject: RE: BS: Random Traces From All Over
RECREATING THE WORLD INSIDE YOUR HEAD. The first use of
individualized virtual-reality sounds in a functional MRI (fMRI)
environment to reproduce a naturalistic acoustic experience for
studying brain function might provide a better explanation of the
*cocktail party* effect-the process by which we try to make sense
of a conversation at a crowded party even as several other potentially
distracting conversations proceed at the same time. New brain scans
using fMRI are helping researchers to understand how the brain
segregates objects in space when a person hears, but not necessarily
sees, multiple sources of sound. At Kourosh Saberi's
(saberi@uci.edu) lab at the University of California, Irvine, human
subjects are exposed to several sounds.

Sometimes the sounds come from different locations near the subject, while sometimes several sounds come from a single location. When looking at fMRI scans
showing areas of enhanced blood flow, which provides 2-mm-resolution
maps of brain activity, the U.C. Irvine scientists report two main
results.

First, no specific brain region accounts exclusively for
identifying auditory motion, in contrast to the visual cortex which
does have specific motion-sensing regions.

And second, spatial auditory information seems to be processed in a neural region,
called the Planum Temporale, in a way that can facilitate the
segregation of multiple sound sources.

(ASA meeting talk 2aPP8,
http://www.acoustics.org/press/)