Neuroscientists unlock shared brain codes

October 20, 2011

A team of neuroscientists at Dartmouth College has shown that different individuals' brains use the same, common neural code to recognize complex visual images.

The paper, "A common, high-dimensional model of the neural representational space in human ventral temporal ," is in the October 20, 2011, issue of the journal, Neuron. The lead author of the paper is James Haxby, the Evans Family Distinguished Professor of in the Department of Psychological and . Haxby is also the Director of the Cognitive Neuroscience Center at Dartmouth and a professor in the Center for Mind/Brain Sciences at the University of Trento in Italy. Swaroop Guntupalli, a graduate student in Haxby's laboratory, developed the software for the new methods and ran the tests of their validity.

Haxby developed a new method called hyperalignment to create this common code and the parameters that transform an individual's patterns into the code.

The parameters are a set of numbers that act like a combination that unlocks that individual's brain's code, Haxby said, allowing activity patterns in that person's brain to be decoded – specifying the that evoked those patterns -- by comparing them to patterns in other people's brains.

"For example, patterns of brain activity evoked by viewing a movie can be decoded to identify precisely which part of the movie an individual was watching by comparing his or her brain activity to the brain activity of other people watching the same movie," said Haxby.

When someone looks at the world, visual images are encoded into patterns of brain activity that capture all of the subtleties that make it possible to recognize an unlimited variety of objects, animals, and actions.

"Although the goal of this work was to find the common code, these methods can now be used to see how brain codes vary across individuals because of differences in visual experience due to training, such as that for air traffic controllers or radiologists, to cultural background, or to factors such as genetics and clinical disorders," he said.

Because of variability in brain anatomy, brain decoding had required separate analysis of each individual. Although detailed analysis of an individual could break that person's brain code, it didn't say anything about the brain code for a different person. In the paper, Haxby shows that all individuals use a common code for visual recognition, making it possible to identify specific patterns of brain activity for a wide range of visual images that are the same in all brains.

As a result of their research, the team showed that a pattern of brain activity in one individual can be decoded by finding the picture or movie that evoked the same pattern in other individuals.

Participants in the study watched the movie Raiders of the Lost Ark while their patterns of brain activity were measured using fMRI. In two separate experiments, they viewed still images of seven categories of faces and objects – male and female human faces, monkey faces, dog faces, shoes, chairs and houses – or six animal species – squirrel monkeys, ring-tailed lemurs, mallards, yellow-throated warblers, ladybugs and luna moths. Analysis of the brain evoked by the movie produced the common code. Once the patterns were in the common code, including responses that were not evoked by the movie, distinct patterns were detected that were common across individuals and specific for fine distinctions, such as monkey versus dog faces, squirrel monkeys versus lemurs.

Explore further: New study examines brain processes behind facial recognition

Related Stories

New study examines brain processes behind facial recognition

April 18, 2011
When you think you see a face in the clouds or in the moon, you may wonder why it never seems to be upside down.

Brain imaging reveals the movies in our mind

September 22, 2011
Imagine tapping into the mind of a coma patient, or watching one's own dream on YouTube. With a cutting-edge blend of brain imaging and computer simulation, scientists at the University of California, Berkeley, are bringing ...

Recommended for you

Researchers find monkey brain structure that decides if viewed objects are new or unidentified

August 18, 2017
A team of researchers working at the University of Tokyo School of Medicine has found what they believe is the part of the monkey brain that decides if something that is being viewed is recognizable. In their paper published ...

How whip-like cell appendages promote bodily fluid flow

August 18, 2017
Researchers at Nagoya University have identified a molecule that enables cell appendages called cilia to beat in a coordinated way to drive the flow of fluid around the brain; this prevents the accumulation of this fluid, ...

Study of nervous system cells can help to understand degenerative diseases

August 18, 2017
The results of a new study show that many of the genes expressed by microglia differ between humans and mice, which are frequently used as animal models in research on Alzheimer's disease and other neurodegenerative disorders.

Researchers make surprising discovery about how neurons talk to each other

August 17, 2017
Researchers at the University of Pittsburgh have uncovered the mechanism by which neurons keep up with the demands of repeatedly sending signals to other neurons. The new findings, made in fruit flies and mice, challenge ...

How we recall the past: Neuroscientists discover a brain circuit dedicated to retrieving memories

August 17, 2017
When we have a new experience, the memory of that event is stored in a neural circuit that connects several parts of the hippocampus and other brain structures. Each cluster of neurons may store different aspects of the memory, ...

Researchers show how particular fear memories can be erased

August 17, 2017
Researchers at the University of California, Riverside have devised a method to selectively erase particular fear memories by weakening the connections between the nerve cells (neurons) involved in forming these memories.


Adjust slider to filter visible comments by rank

Display comments: newest first

2 / 5 (5) Oct 20, 2011
Code? Then dynamic.
At most, pliable hard-wiring rewiring at the rate of input from external stimuli delivered by the senses.

...that evoked the same pattern in other individuals.

Same pattern? Where? Same region, at the most.

People hearing sound when viewing motion?
People when touched hearing sound?

Not even wrong.
1 / 5 (2) Oct 20, 2011
lol Hush1. . .I immediately thought of you after reading this article, and then. . .here you are.
It's not my forte, so I will not comment further.
4 / 5 (1) Oct 20, 2011
Patterns of Persistence
not rated yet Oct 20, 2011
Supplement to persistence:

In ancient times (1976) researchers conjunctured the following, here a partial abstract:

"The interpretation is that visual persistence is an active, continuously operating process rather than a passive neural copy of the stimulus."
not rated yet Oct 21, 2011
What about people that experience extreme sensory stochastic resonance ?
not rated yet Oct 26, 2011
Well, kudos, Isaacsname. Astute.
Extreme? The descriptor makes no sense.

Sensory stochastic resonance appears universal - all life(all cells).

Physically, noise IS a state that is universal.

QM and gravity 'detectives' in search of gravity waves and superpositions and/or entanglements will go the ANY length to avoid noise.

Because the word "extreme" makes no sense to me in the context of sensory stochastic resonance, I can not tell what point you are making with that descriptor.

What do you mean by "extreme?" (How much is extreme?)
What do you mean by "experience?" (What event represent experience?)
What do you mean by "people?" (Who has this?)

There is saturation point, sensory adaptation...

I recommend this literature. In light of the fact that I almost never recommend literature. Yes, 1997 - almost modern.

Your thoughts are of more value, when readers don't have to guess the point you are making.

not rated yet Oct 26, 2011
Hyperalignment does not produce code. Much less common code representing all things physical experienced.

Hyperalignment is hype. A lot of noise. Much ado about nothing.
not rated yet Oct 26, 2011
Not even wrong.
not rated yet Oct 26, 2011
Neuroscientists unlock shared nonsense.

There. Much better.
not rated yet Oct 26, 2011
is this related to?


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.