Featured Research

from universities, journals, and other organizations

How the brain categorizes thousands of objects and actions

Date:
December 19, 2012
Source:
Cell Press
Summary:
Humans perceive numerous categories of objects and actions, but where are these categories represented spatially in the brain? Researchers have undertaken the remarkable task of determining how the brain maps over a thousand object and action categories when subjects watched natural movie clips. The results demonstrate that the brain efficiently represents the diversity of categories in a compact space.

The semantic space projected onto the cortical surface for subjects. Category model weights for each cortical voxel are projected onto PCs 2-4 of the group semantic space, and then assigned a color according to the scheme.
Credit: Huth et al., Neuron, Figure S5

Humans perceive numerous categories of objects and actions, but where are these categories represented spatially in the brain? Researchers reporting in the December 20 issue of the Cell Press journal Neuron present their study that undertook the remarkable task of determining how the brain maps over a thousand object and action categories when subjects watched natural movie clips.

The results demonstrate that the brain efficiently represents the diversity of categories in a compact space. Instead of having a distinct brain area devoted to each category, as previous work had identified, for some but not all types of stimuli, the researchers uncovered that brain activity is organized by the relationship between categories.

"Humans can recognize thousands of categories. Given the limited size of the human brain, it seems unreasonable to expect that every category is represented in a distinct brain area," says first author Alex Huth, a graduate student working in Dr. Jack Gallant's laboratory at the University of California, Berkeley.

The authors proposed that perhaps a more efficient way for the brain to represent object and action categories would be to organize them into a continuous space that reflects the similarity between categories.

To test this hypothesis, they used blood oxygen level-dependent functional magnetic resonance imaging (BOLD fMRI) to measure human brain activity evoked by natural movies in five people. They then mapped out how 1,705 distinct object and action categories are represented across the surface of the cortex of the brain. Their results show that categories are organized as smooth gradients that cover much of the surface of the visual as well as nonvisual cortex, such that similar categories are located next to each other, and notably, this organization was shared across the individuals imaged.

"Discovering the feature space that the brain uses to represent information helps us to recover functional maps across the cortical surface. The brain probably uses similar mechanisms to map other kinds of information across the cortical surface, so our approach should be widely applicable to other areas of cognitive neuroscience," says Dr. Gallant.


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. AlexanderG. Huth, Shinji Nishimoto, AnT. Vu, JackL. Gallant. A Continuous Semantic Space Describes the Representation of Thousands of Object and Action Categories across the Human Brain. Neuron, 2012; 76 (6): 1210 DOI: 10.1016/j.neuron.2012.10.014

Cite This Page:

Cell Press. "How the brain categorizes thousands of objects and actions." ScienceDaily. ScienceDaily, 19 December 2012. <www.sciencedaily.com/releases/2012/12/121219133321.htm>.
Cell Press. (2012, December 19). How the brain categorizes thousands of objects and actions. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2012/12/121219133321.htm
Cell Press. "How the brain categorizes thousands of objects and actions." ScienceDaily. www.sciencedaily.com/releases/2012/12/121219133321.htm (accessed April 24, 2014).

Share This



More Mind & Brain News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Study Says Most Crime Not Linked To Mental Illness

Study Says Most Crime Not Linked To Mental Illness

Newsy (Apr. 22, 2014) A new study finds most crimes committed by people with mental illness are not caused by symptoms of their illness or disorder. Video provided by Newsy
Powered by NewsLook.com
How Smaller Plates And Cutlery Could Make You Feel Fuller

How Smaller Plates And Cutlery Could Make You Feel Fuller

Newsy (Apr. 22, 2014) NBC's "Today" conducted an experiment to see if changing the size of plates and utensils affects the amount individuals eat. Video provided by Newsy
Powered by NewsLook.com
Do We Get Nicer With Age?

Do We Get Nicer With Age?

Newsy (Apr. 22, 2014) A recent report claims personality can change over time as we age, and usually that means becoming nicer and more emotionally stable. Video provided by Newsy
Powered by NewsLook.com
How to Master Motherhood With the Best Work/Life Balance

How to Master Motherhood With the Best Work/Life Balance

TheStreet (Apr. 22, 2014) In the U.S., there are more than 11 million couples trying to conceive at any given time. From helping celebrity moms like Bethanny Frankel to ordinary soon-to-be-moms, TV personality and parenting expert, Rosie Pope, gives you the inside scoop on mastering motherhood. London-born entrepreneur Pope is the creative force behind Rosie Pope Maternity and MomPrep. She explains why being an entrepreneur offers the best life balance for her and tips for all types of moms. Video provided by TheStreet
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:

More Coverage


Scientists Construct First Detailed Map of How the Brain Organizes Everything We See

Dec. 19, 2012 Our eyes may be our window to the world, but how do we make sense of the thousands of images that flood our retinas each day? Scientists have found that the brain is wired to put in order all the ... read more
from the past week

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