Featured Research

from universities, journals, and other organizations

Cracking The Brain's Numerical Code: Researchers Can Tell What Number A Person Has Seen

Date:
September 25, 2009
Source:
Cell Press
Summary:
By carefully observing and analyzing the pattern of activity in the brain, researchers have found that they can tell what number a person has just seen. They can similarly tell how many dots a person has been presented with, according to new research.

By carefully observing and analyzing the pattern of activity in the brain, researchers have found that they can tell what number a person has just seen. They can similarly tell how many dots a person has been presented with, according to a report published online on September 24th in Current Biology, a Cell Press publication.

These findings confirm the notion that numbers are encoded in the brain via detailed and specific activity patterns and open the door to more sophisticated exploration of humans' high-level numerical abilities. Although "number-tuned" neurons have been found in monkeys, scientists hadn't managed to get any farther than particular brain regions before now in humans.

"It was not at all guaranteed that with functional imaging it would be possible to pick this up," said Evelyn Eger of INSERM in France. "In the monkey, neurons preferring one or the other numerosity appear highly intermixed among themselves as well as with neurons responding to other things, so it might seem highly unlikely that with fMRI [functional magnetic resonance imaging] at 1.5 mm resolution—where one voxel contains many thousands of neurons—one would be able to detect differences in activity patterns between individual numbers. The fact that this worked means that there is probably a somewhat more structured layout of preferences for individual numbers that has yet to be revealed by neurophysiological methods."

The researchers presented ten study participants with either number symbols or dots while their brains were scanned with fMRI. They then used a multivariate analysis method to devise a way of decoding the numbers or number of dots people had observed.

Although the brain patterns corresponding to number symbols differed somewhat from those for the same number of objects, the numerosity of dot sets can be predicted above chance from the brain activation patterns evoked by digits, the researchers show. That doesn't work the other way around, however.

At least for small numbers of dots, the researchers did find that the patterns change gradually in a way that reflects the ordered nature of the numbers—allowing one to conclude that 6 is between 5 and 7, for instance. In the case of digits, the researchers could not detect that same gradual change, suggesting that their methods are not yet sensitive enough or that digits are in fact coded as more precise, discrete entities.

The methods used in the new study may ultimately help to unlock how the brain makes more sophisticated calculations, the researchers say.

"With these codes, we are only beginning to access the most basic building blocks that symbolic math probably relies on," Eger said. "We still have no clear idea of how these number representations interact and are combined in mathematical operations, but the fact that we can resolve them in humans gives hope that at some point we can come up with paradigms that let us address this."

The researchers include Evelyn Eger, INSERM U562, Gif/Yvette, France, NeuroSpin, Institut d'Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a` l'E´ nergie Atomique, Gif/Yvette, France, Universite´ Paris-Sud, Orsay, France; Vincent Michel, NeuroSpin, Institut d'Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a` l'E´ nergie Atomique, Gif/Yvette, France, Universite´ Paris-Sud, Orsay, France, Parietal Team, Institut National de Recherche en Informatique et en Automatique (INRIA) Saclay-Iˆle-de-France, Orsay, France; Bertrand Thirion, NeuroSpin, Institut d'Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a` l'E´ nergie Atomique, Gif/Yvette, France, Parietal Team, Institut National de Recherche en Informatique et en Automatique (INRIA) Saclay-Iˆle-de-France, Orsay, France; Alexis Amadon, NeuroSpin, Institut d'Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a` l'E´ nergie Atomique, Gif/Yvette, France, Laboratoire de Resonance Magnetique Nucleaire, Gif/Yvette, France; Stanislas Dehaene, INSERM U562, Gif/Yvette, France, NeuroSpin, Institut d'Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a` l'E´ nergie Atomique, Gif/Yvette, France, Universite´ Paris-Sud, Orsay, France; and Andreas Kleinschmidt, INSERM U562, Gif/Yvette, France, NeuroSpin, Institut d'Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a` l'E´ nergie Atomique, Gif/Yvette, France, Universite´ Paris-Sud, Orsay, France.


Story Source:

The above story is based on materials provided by Cell Press. Note: Materials may be edited for content and length.


Journal Reference:

  1. Evelyn Eger, Vincent Michel, Bertrand Thirion, Alexis Amadon, Stanislas Dehaene, and Andreas Kleinschmidt. Deciphering Cortical Number Coding from Human Brain Activity Patterns. Current Biology, 2009; DOI: 10.1016/j.cub.2009.08.047

Cite This Page:

Cell Press. "Cracking The Brain's Numerical Code: Researchers Can Tell What Number A Person Has Seen." ScienceDaily. ScienceDaily, 25 September 2009. <www.sciencedaily.com/releases/2009/09/090924123306.htm>.
Cell Press. (2009, September 25). Cracking The Brain's Numerical Code: Researchers Can Tell What Number A Person Has Seen. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2009/09/090924123306.htm
Cell Press. "Cracking The Brain's Numerical Code: Researchers Can Tell What Number A Person Has Seen." ScienceDaily. www.sciencedaily.com/releases/2009/09/090924123306.htm (accessed October 23, 2014).

Share This



More Computers & Math News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Chameleon Camouflage to Give Tanks Cloaking Capabilities

Chameleon Camouflage to Give Tanks Cloaking Capabilities

Reuters - Innovations Video Online (Oct. 22, 2014) — Inspired by the way a chameleon changes its colour to disguise itself; scientists in Poland want to replace traditional camouflage paint with thousands of electrochromic plates that will continuously change colour to blend with its surroundings. The first PL-01 concept tank prototype will be tested within a few years, with scientists predicting that a similar technology could even be woven into the fabric of a soldiers' clothing making them virtually invisible to the naked eye. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Internet of Things Aims to Smarten Your Life

Internet of Things Aims to Smarten Your Life

AP (Oct. 22, 2014) — As more and more Bluetooth-enabled devices are reaching consumers, developers are busy connecting them together as part of the Internet of Things. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Google's Inbox Is The Latest Gmail Competitor

Google's Inbox Is The Latest Gmail Competitor

Newsy (Oct. 22, 2014) — Google's new e-mail app is meant for greater personalization and allows users to better categorize their mail, but Gmail isn't going away just yet. Video provided by Newsy
Powered by NewsLook.com
Free Math App Is A Teacher's Worst Nightmare

Free Math App Is A Teacher's Worst Nightmare

Newsy (Oct. 22, 2014) — New photo-recognition software from MicroBlink, called PhotoMath, solves linear equations and simple math problems with step-by-step results. 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

 

Space & Time

Matter & Energy

Computers & Math

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