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 determi
|Contact: Abby Vogel Robinson|
Georgia Institute of Technology Research News