Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study reveals neural basis of rapid brain adaptation

23.11.2010
You detect an object flying at your head. What do you do? You probably first move out of the way -- and then you try to determine what the object is. Your brain is able to quickly switch from detecting an object moving in your direction to determining what the object is through a phenomenon called adaptation.

A new study in the Nov. 21 advance online edition of the journal Nature Neuroscience details the biological basis of this ability for rapid adaptation: neurons located at the beginning of the brain's sensory information pathway that change their level of simultaneous firing.

This modification in neuron firing alters the nature of the information being relayed, which enhances the brain's ability to discriminate between different sensations -- at the expense of degrading its ability to detect the sensations themselves.

"Previous studies have focused on how brain adaptation influences how much information from the outside world is being transmitted by the thalamus to the cortex, but we show that it is also important to focus on what information is being transmitted," said Garrett Stanley, an associate professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

In addition to Stanley, Coulter Department research scientist Qi Wang and Harvard Medical School Neurobiology Department research fellow Roxanna Webber contributed to this work, which is supported by the National Institutes of Health.

For the experiments, Stanley and Wang moved a rat's whisker to generate a sensory input. Moving whiskers at different speeds or at different angles produced sensory inputs that could be discriminated. This sensory experience is analogous to an individual moving a fingertip across a surface and perceiving the surface as smooth or rough. While the whiskers were being moved, the researchers recorded neural signals simultaneously from different parts of the animal's brain to determine what information was being transmitted.

"Neuroscientists know a lot about different parts of the brain, but we don't know a lot about how they talk to each other. Recording how neurons are simultaneously communicating with each other in different parts of the brain and studying how the communication changes in different situations is a big step in this field," said Stanley.

The results from the experiments showed that adaptation shifted neural activity from a state in which the animal was good at detecting the presence of a sensory input to a state in which the animal was better at discriminating between sensory inputs. In addition, adaptation enhanced the ability to discriminate between deflections of the whiskers in different angular directions, pointing to a general phenomenon.

"Adaptation differentially influences the thalamus and cortex in a manner that fundamentally changes the nature of information conveyed about whisker motion," explained Stanley. "Our results provide a direct link between the long-observed phenomenon of enhanced sensory performance with adaptation and the underlying neurophysiological representation in the primary sensory cortex."

The thalamus serves as a relay station between the outside world and the cortex. Areas of the cortex receive and process information related to vision, audition and touch from the thalamus.

The study also revealed that information the cortex receives from the thalamus is transformed as it travels through the pathway due to a change in the level of simultaneous firing of neurons in the thalamus. The researchers found that the effect of adaptation on the synchrony of neurons in the thalamus was the key element in the shift between sensory input detection and discrimination.

"There is a switching of the circuit to a different function. The same neurons do two different things and switch quickly, in a matter of seconds or milliseconds, through a change in the synchronization across neurons," explained Stanley. "If we think of the neurons firing like members of an audience clapping hands, then the sound of the clapping becomes louder when they all clap together."

In the future, the techniques used in this study may be valuable for probing the effects of brain injury on this pathway and others, as a variety of different diseases and disorders act to change the degree of synchronization of neurons in the brain, resulting in harmful effects.

This project is supported by the National Institutes of Health (NIH) (Award No. R01NS48285). The content is solely the responsibility of the principal investigator and does not necessarily represent the official view of the NIH.

Abby Vogel Robinson | EurekAlert!
Further information:
http://www.gatech.edu

More articles from Studies and Analyses:

nachricht Multi-year study finds 'hotspots' of ammonia over world's major agricultural areas
17.03.2017 | University of Maryland

nachricht Diabetes Drug May Improve Bone Fat-induced Defects of Fracture Healing
17.03.2017 | Deutsches Institut für Ernährungsforschung Potsdam-Rehbrücke

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short

23.03.2017 | Life Sciences

Researchers use light to remotely control curvature of plastics

23.03.2017 | Power and Electrical Engineering

Sea ice extent sinks to record lows at both poles

23.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>