Featured Research

from universities, journals, and other organizations

How the brain forms categories

Date:
October 19, 2012
Source:
Research Institute of Molecular Pathology
Summary:
Neurobiologists have investigated how the brain is able to group external stimuli into stable categories. They found the answer in the discrete dynamics of neuronal circuits.

Illustration. How the brain forms categories.
Credit: Image courtesy of Research Institute of Molecular Pathology

How do we manage to recognize a friend's face, regardless of the light conditions, the person's hairstyle or make-up? Why do we always hear the same words, whether they are spoken by a man or woman, in a loud or soft voice? It is due to the amazing skill of our brain to turn a wealth of sensory information into a number of defined categories and objects. The ability to create constants in a changing world feels natural and effortless to a human, but it is extremely difficult to train a computer to perform the task.

Related Articles


At the IMP in Vienna, neurobiologist Simon Rumpel and his post-doc Brice Bathellier have been able to show that certain properties of neuronal networks in the brain are responsible for the formation of categories. In experiments with mice, the researchers produced an array of sounds and monitored the activity of nerve cell-clusters in the auditory cortex. They found that groups of 50 to 100 neurons displayed only a limited number of different activity-patterns in response to the different sounds.

The scientists then selected two basis sounds that produced different response patterns and constructed linear mixtures from them. When the mixture ratio was varied continuously, the answer was not a continuous change in the activity patters of the nerve cells, but rather an abrupt transition. Such dynamic behavior is reminiscent of the behavior of artificial attractor-networks that have been suggested by computer scientists as a solution to the categorization problem.

The findings in the activity patters of neurons were backed up by behavioral experiments with mice. The animals were trained to discriminate between two sounds. They were then exposed to a third sound and their reaction was tracked. Whether the answer to the third tone was more like the reaction to the first or the second one, was used as an indicator of the similarity of perception. By looking at the activity patters in the auditory cortex, the scientists were able to predict the reaction of the mice.

The new findings that are published in the current issue of the journal Neuron, demonstrate that discrete network states provide a substrate for category formation in brain circuits. The authors suggest that the hierarchical structure of discrete representations might be essential for elaborate cognitive functions such as language processing.


Story Source:

The above story is based on materials provided by Research Institute of Molecular Pathology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Brice Bathellier, Lyubov Ushakova, Simon Rumpel. Discrete Neocortical Dynamics Predict Behavioral Categorization of Sounds. Neuron, 2012; 76 (2): 435 DOI: 10.1016/j.neuron.2012.07.008

Cite This Page:

Research Institute of Molecular Pathology. "How the brain forms categories." ScienceDaily. ScienceDaily, 19 October 2012. <www.sciencedaily.com/releases/2012/10/121019092933.htm>.
Research Institute of Molecular Pathology. (2012, October 19). How the brain forms categories. ScienceDaily. Retrieved March 5, 2015 from www.sciencedaily.com/releases/2012/10/121019092933.htm
Research Institute of Molecular Pathology. "How the brain forms categories." ScienceDaily. www.sciencedaily.com/releases/2012/10/121019092933.htm (accessed March 5, 2015).

Share This


More From ScienceDaily



More Mind & Brain News

Thursday, March 5, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Former NFL Players Donate Brains to Science

Former NFL Players Donate Brains to Science

Reuters - US Online Video (Mar. 3, 2015) Super Bowl champions Sidney Rice and Steve Weatherford donate their brains, post-mortem, to scientific research into repetitive brain trauma. Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
Alzheimer's Protein Plaque Found In 20-Year-Olds

Alzheimer's Protein Plaque Found In 20-Year-Olds

Newsy (Mar. 3, 2015) Researchers found an abnormal protein associated with Alzheimer&apos;s disease in the brains of 20-year-olds. Video provided by Newsy
Powered by NewsLook.com
This Nasal Treatment Could Help Ease Migraine Pain

This Nasal Treatment Could Help Ease Migraine Pain

Newsy (Mar. 2, 2015) Researchers gave lidocaine to 112 patients, and about 88 percent of the subjects said they needed less migraine-relief medicine the next day. Video provided by Newsy
Powered by NewsLook.com
How Facebook Use Can Lead To Depression

How Facebook Use Can Lead To Depression

Newsy (Mar. 1, 2015) Margaret Duffy of the University of Missouri talks about her study on the social network and the envy and depression that Facebook use can cause. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins