Yale team finds neural thermostat keeps brain running efficiently

Jan 13, 2010

Our energy-hungry brains operate reliably and efficiently while processing a flood of sensory information, thanks to a sort of neuronal thermostat that regulates activity in the visual cortex, Yale researchers have found.

The actions of inhibitory allow the to save energy by suppressing non-essential and processing only key information, according to research published in the January 13 issue of the journal Neuron.

"It's called the iceberg phenomenon, where only the tip is sharply defined yet we are aware that there is a much larger portion underwater that we can not see," said David McCormick, the Dorys McConnell Duberg Professor of Neurobiology at Yale School of Medicine, researcher of the Kavli Institute of Neuroscience and co-senior author of the study. "These inhibitory neurons set the water level and control how much of the iceberg we see. We don't need to see the entire iceberg to know that it is there."

The brain uses the highest percentage of the body's energy, so scientists have long wondered how it can operate both efficiently and reliably when processing a deluge of sensory information. Most studies of vision have concentrated on activity of excitatory neurons that fire when presented with simple stimuli, such as bright or dark bars. The Yale team wanted to measure what happens outside of the classical field of vision when the brain has to deal with more complex scenes in real life.

By studying brains of animals watching movies of natural scenes, the Yale team found that inhibitory cells in the visual cortex control how the excitatory cells interact with each other.

"We found that these inhibitory cells take a lead role in making the operate in a sparse and reliable manner," McCormick said.

Explore further: Researchers link gene to increased dendritic spines – a signpost of autism

add to favorites email to friend print save as pdf

Related Stories

Picower research finds unexpected activity in visual cortex

Mar 16, 2006

For years, neural activity in the brain's visual cortex was thought to have only one job: to create visual perceptions. A new study by researchers at MIT's Picower Institute for Learning and Memory shows that visual cortical ...

Rare cell prevents rampant brain activity

Mar 02, 2007

One of the mysteries of the brain is how it avoids ending up in a state of chaos, something which happens only on exceptional occasions, when it can lead to epileptic fits. Scientists at Karolinska Institutet have now uncovered ...

Modeling how we see natural scenes

May 21, 2008

Sophisticated mathematical modeling methods and a “CatCam” that captures feline-centric video of a forest are two elements of a new effort to explain how the brain’s visual circuitry processes real scenes. The new model ...

Brain energy use key to understanding consciousness

Jun 16, 2009

High levels of brain energy are required to maintain consciousness, a finding which suggests a new way to understand the properties of this still mysterious state of being, Yale University researchers report.

What drives brain changes in macular degeneration?

Mar 03, 2009

In macular degeneration, the most common form of adult blindness, patients progressively lose vision in the center of their visual field, thereby depriving the corresponding part of the visual cortex of input. Previously, ...

Recommended for you

Scientists show rise and fall of brain volume

1 hour ago

(Medical Xpress)—We can witness our bodies mature, then gradually grow wrinkled and weaker with age, but it is only recently that scientists have been able to track a similar progression in the nerve bundles ...

'Dimmer switch' for mood disorders discovered

18 hours ago

Researchers at University of California, San Diego School of Medicine have identified a control mechanism for an area of the brain that processes sensory and emotive information that humans experience as ...

User comments : 0