Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


In-sync brain waves hold memory of objects just seen

Brain's code for visual working memory deciphered in monkeys -- NIH-funded study

The brain holds in mind what has just been seen by synchronizing brain waves in a working memory circuit, an animal study supported by the National Institutes of Health suggests. The more in-sync such electrical signals of neurons were in two key hubs of the circuit, the more those cells held the short-term memory of a just-seen object.

Charles Gray, Ph.D., of Montana State University, Bozeman, a grantee of NIH's National Institute of Mental Health (NIMH), and colleagues, report their findings Nov. 1, 2012, online, in the journal Science Express.

"This work demonstrates, for the first time, that there is information about short term memories reflected in in-sync brainwaves," explained Gray.

"The Holy Grail of neuroscience has been to understand how and where information is encoded in the brain. This study provides more evidence that large scale electrical oscillations across distant brain regions may carry information for visual memories," said NIMH director Thomas R. Insel, M.D.

Prior to the study, scientists had observed synchronous patterns of electrical activity between the two circuit hubs after a monkey saw an object, but weren't sure if the signals actually represent such short-term visual memories in the brain. Rather, it was thought that such neural oscillations might play the role of a traffic cop, directing information along brain highways.

To find out more, Gray, Rodrigo Salazar Ph.D., and Nick Dotson of Montana State and Steven Bressler, Ph.D., at Florida Atlantic University, Boca Raton, recorded electrical signals from groups of neurons in both hubs of two monkeys performing a visual working memory task. To earn a reward, the monkeys had to remember an object – or its location – that they saw momentarily on a computer screen and correctly match it. The researchers expected to see the telltale boost in synchrony during a delay period immediately after an object disappeared from the screen, when the monkey had to hold information briefly in mind.

The degree of synchronous activity, or coherence, between cells in the areas was plotted for different objects the monkeys saw.

Brain waves of many neurons in the two hubs, called the prefrontal cortex and posterior parietal cortex, synchronized to varying degrees – depending on an object's identity (see picture below). This and other evidence indicated that neurons in these hubs are selective for particular features in the visual field and that synchronization in the circuit carries content-specific information that might contribute to visual working memory.

The researchers also determined that the parietal cortex was more influential than the prefrontal cortex in driving this process. Previously, many researchers had thought that the firing rate of single neurons in the prefrontal cortex, the brain's executive, is the major player in working memory.

Since synchronized oscillations between populations of cells distinguished between visual stimuli, it's theoretically possible to determine the correct answers for the matching tasks the monkeys performed simply by reading their brain waves. Similarly, synchrony between cell populations in the two hubs also distinguished between locations. So the location of visual information, like object identity, also appears to be represented by synchronous brain waves. Again, researchers previously thought that these functions had mostly to do with the firing rates of neurons.

So the new findings may upturn prevailing theory.

In addition to NIMH, the research was also supported by the NIH's National Institute on Neurological Disorders and Stroke (NINDS).

Jules Asher | EurekAlert!
Further information:

More articles from Studies and Analyses:

nachricht Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung

nachricht High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

New method increases energy density in lithium batteries

24.10.2016 | Power and Electrical Engineering

International team discovers novel Alzheimer's disease risk gene among Icelanders

24.10.2016 | Life Sciences

New bacteria groups, and stunning diversity, discovered underground

24.10.2016 | Life Sciences

More VideoLinks >>>