(Press-News.org) MADISON, Wis. -- As real as that daydream may seem, its path through your brain runs opposite reality.
Aiming to discern discrete neural circuits, researchers at the University of Wisconsin-Madison have tracked electrical activity in the brains of people who alternately imagined scenes or watched videos.
"A really important problem in brain research is understanding how different parts of the brain are functionally connected. What areas are interacting? What is the direction of communication?" says Barry Van Veen, a UW-Madison professor of electrical and computer engineering. "We know that the brain does not function as a set of independent areas, but as a network of specialized areas that collaborate."
Van Veen, along with Giulio Tononi, a UW-Madison psychiatry professor and neuroscientist, Daniela Dentico, a scientist at UW-Madison's Waisman Center, and collaborators from the University of Liege in Belgium, published results recently in the journal NeuroImage. Their work could lead to the development of new tools to help Tononi untangle what happens in the brain during sleep and dreaming, while Van Veen hopes to apply the study's new methods to understand how the brain uses networks to encode short-term memory.
During imagination, the researchers found an increase in the flow of information from the parietal lobe of the brain to the occipital lobe -- from a higher-order region that combines inputs from several of the senses out to a lower-order region.
In contrast, visual information taken in by the eyes tends to flow from the occipital lobe -- which makes up much of the brain's visual cortex -- "up" to the parietal lobe.
"There seems to be a lot in our brains and animal brains that is directional, that neural signals move in a particular direction, then stop, and start somewhere else," says. "I think this is really a new theme that had not been explored."
The researchers approached the study as an opportunity to test the power of electroencephalography (EEG) -- which uses sensors on the scalp to measure underlying electrical activity -- to discriminate between different parts of the brain's network.
Brains are rarely quiet, though, and EEG tends to record plenty of activity not necessarily related to a particular process researchers want to study.
To zero in on a set of target circuits, the researchers asked their subjects to watch short video clips before trying to replay the action from memory in their heads. Others were asked to imagine traveling on a magic bicycle -- focusing on the details of shapes, colors and textures -- before watching a short video of silent nature scenes.
Using an algorithm Van Veen developed to parse the detailed EEG data, the researchers were able to compile strong evidence of the directional flow of information.
"We were very interested in seeing if our signal-processing methods were sensitive enough to discriminate between these conditions," says Van Veen, whose work is supported by the National Institute of Biomedical Imaging and Bioengineering. "These types of demonstrations are important for gaining confidence in new tools."
INFORMATION:
Scott Gordon
608-265-8592
gordon@engr.wisc.edu
NOTE: A high-resolution photo to accompany this story can be downloaded at http://news.wisc.edu/newsphotos/VanVeen.html
MADISON, Wis. - The influenza virus, like all viruses, is a hijacker. It quietly slips its way inside cells, steals the machinery inside to make more copies of itself, and then -- having multiplied -- bursts out of the cell to find others to infect.
Most drugs currently used to treat influenza are designed to attack the virus, to render it incapacitated. But influenza viruses are sneaky, capable of mutating to avoid destruction by the drug.
In a comprehensive new study published today in the journal Cell Host and Microbe, the University of Wisconsin-Madison's Yoshihiro ...
EUGENE, Ore. -- Nov. 20, 2014 -- A potential path to identify imperfections and improve the quality of nanomaterials for use in next-generation solar cells has emerged from a collaboration of University of Oregon and industry researchers.
To increase light-harvesting efficiency of solar cells beyond silicon's limit of about 29 percent, manufacturers have used layers of chemically synthesized semiconductor nanocrystals. Properties of quantum dots that are produced are manipulated by controlling the synthetic process and surface chemical structure.
This process, however, ...
CHAMPAIGN, Ill. -- The majority of preschoolers may not be getting the amount of sleep they need each night, placing them at higher risk of being overweight or obese within a year, according to a new study.
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"The only factor of the four that we investigated that ...
Washington, DC--Levels of testosterone and other naturally-occurring reproductive hormones play a limited role in driving menopausal women's interest in sex and sexual function, according to a new study published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism.
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"While levels of testosterone and other reproductive ...
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People develop Type 2 diabetes when their bodies become resistant to the hormone insulin, which carries sugar from the blood to cells. This leads to excess sugar in the bloodstream. The U.S. Centers for Disease Control and Prevention projects about 40 percent of Americans will develop ...
Enzymes carry out fundamental biological processes such as photosynthesis, nitrogen fixation and respiration, with the help of clusters of metal atoms as "active" sites. But scientists lack basic information about their function because the states thought to be critical to their chemical abilities cannot be experimentally observed.
Now, researchers at Princeton University have reported the first direct observation of the electronic states of iron-sulfur clusters, common to many enzyme active sites. Published on August 31 in the journal Nature Chemistry, the states were ...
LIVERMORE, California -- Using ocean observations and a large suite of climate models, Lawrence Livermore National Laboratory scientists have found that long-term salinity changes have a stronger influence on regional sea level changes than previously thought.
"By using long-term observed estimates of ocean salinity and temperature changes across the globe, and contrasting these with model simulations, we have uncovered the unexpectedly large influence of salinity changes on ocean basin-scale sea level patterns," said LLNL oceanographer Paul Durack, lead author of a paper ...
BANGALORE, INDIA (November 20, 2014) - Participation of non-scientists as volunteers in conservation can play a significant role in saving wildlife, finds a new scientific research led by Duke University, USA, in collaboration with Wildlife Conservation Society and Centre for Wildlife Studies, Bengaluru.
The study has shown that citizen science projects greatly contribute to 'increased environmental awareness among the general public'. It also reported direct impacts on conservation including - shift in formal profession by volunteers to become conservationists, initiation ...
Moderate rainfall was occurring around the center of Tropical Storm Adjali before it dissipated, according to data from NASA and the Japan Aerospace Exploration Agency's Global Precipitation Measurement or GPM satellites.
Adjali became the first named storm of the Southwest Indian Ocean 2014/2015 cyclone season when it formed on November 16, 2014. Adjali became a strong tropical storm the next day and just two days later started to dissipate.
The GPM observatory captured data on Adjali's rainfall rates on Nov. 18. GPM's Microwave Imager (GMI) instrument is similar to ...
This new survey was released November 19 as a Web First by Health Affairs. The full text is available free until November 26.
International Survey Of Older Adults Finds Shortcomings In Access, Coordination, And Patient-Centered Care
By Robin Osborn, Donald Moulds, David Squires, Michelle M. Doty, and Chloe Anderson
All authors are affiliated with The Commonwealth Fund in New York.
This study was supported by The Commonwealth Fund and also will appear in the December issue of Health Affairs.
The study surveyed 15,617 adults ages sixty-five and older in Australia, ...
