Cold Spring Harbor, N.Y. Just as we visually map a room by spatially identifying the objects in it, we map our aural world based on the frequencies of sounds. The neurons within the brain's "hearing center"the auditory cortexare organized into modules that each respond to sounds within a specific frequency band. But how responses actually emanate from this complex network of neurons is still a mystery.
A team of scientists led by Anthony Zador, M.D., Ph.D., Professor and Chair of the Neuroscience program at Cold Spring Harbor Laboratory (CSHL) has come a step closer to unraveling this puzzle. The scientists probed how the functional connectivity among neurons within the auditory cortex gives rise to a "map" of acoustic space.
"What we learned from this approach has put us in a position to investigate and understand how sound responsiveness arises from the underlying circuitry of the auditory cortex," says Zador. His team's findings appear online, ahead of print, on October 17th in Nature Neuroscience.
Neuronal organization within the auditory cortex fundamentally differs from the organization within brain regions that process sensory inputs such as sight and sensation. For instance, the relative spatial arrangement of sight receptors in the retina (the eyes' light-sensitive inner surface) is directly represented as a two-dimensional "retinotopic" map in the brain's visual cortex.
In the auditory system, however, the organization of sound receptors in the cochlea the snail-like structure in the ear is one-dimensional. Cochlear receptors near the outer edge recognize low-frequency sounds whereas those whereas those near the inside of the cochlea are tuned to higher frequencies. This low-to-high distribution, called 'tonotopy,' is preserved along one dimension in the auditory cortex, with neurons tuned to high and low frequencies arranged in a head-to-tail gradient.
"Because sound is intrinsically a one-dim
'/>"/>
| Contact: Hema Bashyam bashyam@cshl.edu 516-367-6822 Cold Spring Harbor Laboratory Source:Eurekalert |
Related biology news :
1. Jefferson scientists deliver toxic genes to effectively kill pancreatic cancer cells
2. Scientists identify novel inhibitor of human microRNA
3. Argonne scientists peer into heart of compound that may detect chemical, biological weapons
4. MU scientists go green with gold, distribute environmentally friendly nanoparticles
5. Scientists identify gene that may contribute to improved rice yield
6. Scientists discover why a mothers high-fat diet contributes to obesity in her children
7. MU scientists see how HIV matures into an infection
8. Earth scientists keep an eye on Texas
9. Thinking it through: Scientists call for policy to guide biofuels industry toward sustainability
10. Scientists identify a molecule that coordinates the movement of cells
11. Scientists Find new migratory patterns for Mediterranean and Western Atlantic bluefin tuna
| Copyright © 2003-2012 Bio-Medicine. All rights reserved. ABOUT | CONTACT US | DISCLAIMER | PRIVACY POLICY | TERMS AND CONDITIONS |  |