Neuroscientists show how neurons respond to sequences of familiar objects

A new study from Carnegie Mellon researchers shows how neurons react to a stream of images. Test subjects were trained to look at images of items (below) until those images became familiar. Credit: Center for Neural Basis of Cognition

The world grows increasingly more chaotic year after year, and our brains are constantly bombarded with images. A new study from Center for the Neural Basis of Cognition (CNBC), a joint project between Carnegie Mellon University and the University of Pittsburgh, reveals how neurons in the part of the brain responsible for recognizing objects respond to being shown a barrage of images. The study is published online by Nature Neuroscience.

The CNBC researchers showed animal subjects a rapid succession of images, some that were new, and some that the subjects had seen more than 100 times. The researchers measured the electrical response of in the inferotemporal cortex, an essential part of the visual system and the part of the responsible for object recognition.

In previous studies, researchers found that when subjects were shown a single, familiar image, their neurons responded less strongly than when they were shown an unfamiliar image. However, in the current study, the CNBC researchers found that when subjects were exposed to familiar and unfamiliar images in a rapid succession, their neurons—especially the —fired much more strongly and selectively to images the subject had seen many times before.

"It was such a dramatic effect, it leapt out at us," said Carl Olson, a professor at Carnegie Mellon. "You wouldn't expect there to be such deep changes in the brain from simply making things familiar. We think this may be a mechanism the brain uses to track a rapidly changing visual environment."

The researchers then ran a similar experiment in which they used themselves as subjects, recording their brain activity using EEG. They found that the humans' brains responded similarly to the animal subjects' brains when presented with familiar or unfamiliar images in rapid succession. In future studies, they hope to link these changes in the brain to improvements in perception and cognition.

More information: Image familiarization sharpens response dynamics of neurons in inferotemporal cortex, Nature Neuroscience, DOI: 10.1038/nn.3794

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

US aims for traumatic brain injury clinical trial success

1 hour ago

An unprecedented, public-private partnership funded by the Department of Defense (DoD) is being launched to drive the development of better-run clinical trials and may lead to the first successful treatments for traumatic ...

New learning mechanism for individual nerve cells

6 hours ago

The traditional view is that learning is based on the strengthening or weakening of the contacts between the nerve cells in the brain. However, this has been challenged by new research findings from Lund University in Sweden. ...

USC memory scientist Richard Thompson dies at 84

23 hours ago

Richard F. Thompson, the University of Southern California neuroscientist whose experiments with rabbits led to breakthrough discoveries on how memories are physically stored in the brain, has died. He was 84.

User comments