BRAINWAVES CAN PREDICT AUDIENCE REACTION OF TELEVISION PROGRAMMING
From the FMS Global News Desk of Jeanne Hambleton Released: 29-Jul-2014
Source Newsroom: Georgia Institute of Technology Nature Communications
Newswise — Media and marketing experts have long sought a reliable method of forecasting responses from the general population to future products and messages. According to a study conducted at the City College of New York (CCNY) in partnership with Georgia Tech, it appears that the brain responses of just a few individuals are a remarkably strong predictor.
By analyzing the brainwaves of 16 individuals as they watched mainstream television content, researchers were able to accurately predict the preferences of large TV audiences, up to 90 percent in the case of Super Bowl commercials. The findings appear in a paper entitled “Audience Preferences Are Predicted by Temporal Reliability of Neural Processing,” which was just published in the latest edition of Nature Communications.
“Alternative methods such as self-reports are fraught with problems as people conform their responses to their own values and expectations,” said Jacek Dmochowski, lead author of the paper and a postdoctoral fellow at CCNY at the time the study was being conducted.
However, brain signals measured using electroencephalography (EEG) can, in principle, alleviate this shortcoming by providing immediate physiological responses immune to such self-biasing.
“Our findings show that these immediate responses are in fact closely tied to the subsequent behavior of the general population,” he added.
Lucas Parra, Herbert Kayser Professor of Biomedical Engineering at CCNY and the paper’s senior author explained that, “when two people watch a video, their brains respond similarly – but only if the video is engaging. Popular shows and commercials draw our attention and make our brainwaves very reliable; the audience is literally ‘in-sync’.”
In the study, participants watched scenes from The Walking Dead TV show and several commercials from the 2012 and 2013 Super Bowls. EEG electrodes were placed on their heads to capture brain activity. The reliability of the recorded neural activity was then compared to audience reactions in the general population using publicly available social media data provided by the Harmony Institute and ratings from USA Today’s Super Bowl Ad Meter.
“Brain activity among our participants watching The Walking Dead predicted 40 percent of the associated Twitter traffic,” said Parra. “When brainwaves were in agreement, the number of tweets tended to increase.” Brainwaves also predicted 60 percent of the Nielsen ratings that measure the size of a TV audience.
The study was even more accurate (90 percent) when comparing preferences for Super Bowl ads. For instance, researchers saw very similar brainwaves from their participants as they watched a 2012 Budweiser commercial that featured a beer-fetching dog. The general public voted the ad as their second favorite that year. The study found little agreement in the brain activity among participants when watching a GoDaddy commercial featuring a kissing couple. It was among the worst rated ads in 2012.
The CCNY researchers collaborated with Matthew Bezdek and Eric Schumacher from Georgia Tech to identify which brain regions are involved and explain the underlying mechanisms. Using functional magnetic resonance imaging (fMRI), they found evidence that brainwaves for engaging ads could be driven by activity in visual, auditory and attention brain areas.
“Interesting ads may draw our attention and cause deeper sensory processing of the content,” said Bezdek, a postdoctoral researcher at Georgia Tech’s School of Psychology.
Apart from applications to marketing and film, Parra is investigating whether this measure of attentional draw can be used to diagnose neurological disorders such as attention deficit disorder or mild cognitive decline. Another potential application is to predict the effectiveness of online educational videos by measuring how engaging they are.
MEMORY RELIES ON ASTROCYTES, THE BRAIN’S LESSER KNOWN CELLS
Salk scientists show that the little-known supportive cells are vital in cognitive function
From FMS Global News Desk of Jeanne Hambleton Released: 28-Jul-2014 Source Newsroom: Salk Institute for Biological Studies
Newswise — LA JOLLA—When you are expecting something—like the meal you have ordered at a restaurant—or when something captures your interest, unique electrical rhythms sweep through your brain.
These waves are called gamma oscillations and they reflect a symphony of cells—both excitatory and inhibitory—playing together in an orchestrated way. Though their role has been debated, gamma waves have been associated with higher-level brain function, and disturbances in the patterns have been tied to schizophrenia, Alzheimer’s disease, autism, epilepsy and other disorders.
Now, new research from the Salk Institute shows that little known supportive cells in the brain known as astrocytes may in fact be major players that control these waves.
In a study published July 28 in the Proceedings of the National Academy of Sciences, Salk researchers report a new, unexpected strategy to turn down gamma oscillations by disabling not neurons but astrocytes. In the process, the team showed that astrocytes, and the gamma oscillations they help shape, are critical for some forms of memory.
“This is what could be called a smoking gun,” says co-author Terrence Sejnowski, head of the Computational Neurobiology Laboratory at the Salk Institute for Biological Sciences and a Howard Hughes Medical Institute investigator.
“There are hundreds of papers linking gamma oscillations with attention and memory, but they are all correlational. This is the first time we have been able to do a causal experiment, where we selectively block gamma oscillations and show that it has a highly specific impact on how the brain interacts with the world.”
A collaboration among the labs of Salk professors Sejnowski, Inder Verma and Stephen Heinemann found that activity in the form of calcium signaling in astrocytes immediately preceded gamma oscillations in the brains of mice. This suggested that astrocytes, which use many of the same chemical signals as neurons, could be influencing these oscillations.
To test their theory, the group used a virus carrying tetanus toxin to disable the release of chemicals released selectively from astrocytes, effectively eliminating the cells’ ability to communicate with neighboring cells. Neurons were unaffected by the toxin.
After adding a chemical to trigger gamma waves in the animals’ brains, the researchers found that brain tissue with disabled astrocytes produced shorter gamma waves than in tissue containing healthy cells. And, after adding three genes that would allow the researchers to selectively turn on and off the tetanus toxin in astrocytes at will, they found that gamma waves were dampened in mice whose astrocytes were blocked from signaling. Turning off the toxin reversed this effect.
The mice with the modified astrocytes seemed perfectly healthy. But after several cognitive tests, the researchers found that they failed in one major area: novel object recognition. As expected, healthy mice spent more time with a new item placed in its environment than it did with familiar items. In contrast, the group’s new mutant mouse treated all objects the same.
“That turned out to be a spectacular result in the sense that novel object recognition memory was not just impaired, it was gone—as if we were deleting this one form of memory, leaving others intact,” Sejnowski says.
The results were surprising, in part because astrocytes operate on a seconds – or longer timescale whereas neurons signal far faster, on the millisecond scale. Because of that slower speed, no one suspected astrocytes were involved in the high-speed brain activity needed to make quick decisions.
“What I thought quite unique was the idea that astrocytes, traditionally considered only guardians and supporters of neurons and other cells, are also involved in the processing of information and in other cognitive behavior,” says Verma, a professor in the Laboratory of Genetics and American Cancer Society Professor.
It is not that astrocytes are quick—they are still slower than neurons. But the new evidence suggests that astrocytes are actively supplying the right environment for gamma waves to occur, which in turn makes the brain more likely to learn and change the strength of its neuronal connections.
Sejnowski says that the behavioral result is just the tip of the iceberg. “The recognition system is hugely important,” he says, adding that it includes recognizing other people, places, facts and things that happened in the past. With this new discovery, scientists can begin to better understand the role of gamma waves in recognition memory, he adds.
Collaborators included Hosuk Sean Lee of the Department of Life Sciences in Sogang University in Seoul, South Korea; Andrea Ghetti, Gustavo Dziewczapolski and Juan C. Piña-Crespo of the Molecular Neurobiology Laboratory at Salk; António Pinto-Duarte of the Institute of Pharmacology and Neurosciences, Faculty of Medicine and the Institute of Molecular Medicine Neurosciences Unit at the University of Lisbon in Portugal; Xin Wang of Salk’s Computational Neurobiology Laboratory; Francesco Galimi of Salk and the Department of Biomedical Sciences/Istituto Nazionale di Biostrutture e Biosistemi, University of Sassari Medical School in Sassari, Italy; and Salvador Huitron-Resendiz and Amanda J. Roberts of the Mouse Behavioral Assessment Core at the Scripps Research Institute, in La Jolla, California.
The work was supported by a Salk Innovation Grant, Kavli Innovative Research Awards, a Calouste Gulbenkian Foundation Fellowship, a Life Sciences Research Foundation Pfizer Fellowship, the Brain and Behavior Research Foundation, the Bundy Foundation, Jose Carreras International Leukemia Foundation, the Pew Charitable Trusts, National Science Foundation, Howard Hughes Medical Institute, the Office of Naval Research, and the National Institutes of Health.
About the Salk Institute for Biological Studies:
The Salk Institute for Biological Studies is one of the world’s preeminent basic research institutions, where internationally renowned faculty probe fundamental life science questions in a unique, collaborative and creative environment. Focused both on discovery and on mentoring future generations of researchers, Salk scientists make groundbreaking contributions to our understanding of cancer, aging, Alzheimer’s, diabetes and infectious diseases by studying neuroscience, genetics, cell and plant biology, and related disciplines.
Faculty achievements have been recognized with numerous honors, including Nobel Prizes and memberships in the National Academy of Sciences. Founded in 1960 by polio vaccine pioneer Jonas Salk, MD, the Institute is an independent nonprofit organization and architectural landmark.
BIRTHDAY MATTERS FOR WIRING-UP THE BRAIN’S VISION CENTERS
From the FMS Global News Desk of Jeanne Hambleton Embargo 31-Jul-2014
Source Newsroom: University of California, San Diego Health Sciences Cell Reports
Newswise — Researchers at the University of California, San Diego School of Medicine have evidence suggesting that neurons in the developing brains of mice are guided by a simple but elegant birth order rule that allows them to find and form their proper connections.
The study is published online July 31 in Cell Reports.
“Nothing about brain wiring is haphazard,” said senior author Andrew Huberman, PhD, assistant professor in the Department of Neurosciences, Division of Biological Sciences and Department of Ophthalmology, UC San Diego.
A mature, healthy brain has billions of precisely interconnected neurons. Yet the brain starts with just one neuron that divides and divides – up to 250,000 new neurons per minute at times during early development. The question for biologists has been how do these neurons decide which other neurons to connect to, a process neuroscientists call target selection.
The answer has both fundamental scientific value and clinical relevance. Some researchers believe that autism and other disorders linked to brain development may be caused, in part, by a failure of neurons to properly reposition their axons as needed when mistakes in target selection occur.
To better understand how a young brain gets wired, researchers focused on the development of retinal ganglion cells (RGCs) in mice. These cells connect the eyes and brain. Specifically, the main cell bodies of RGCs reside in the retina but their axons – slender projections along which electrical impulses travel – extend into the centers of the brain that process visual information and give rise to what we commonly think of as “sight,” as well as other light-influenced physiological processes, such as the effect of light on mood.
For the study, scientists tagged RGCs and watched where they directed their axons during development. The experiments revealed that specific types of RGCs target specific areas of the brain, allowing mice to do things such as sense direction of motion, move their eyes and detect changes in daily light cycles. It was also observed that some types of RGCs (such as those that detect brightness and control pupil constriction) are created early in development while others (such as those controlling eye movements) are created later.
The study’s main finding is that early RGCs (those created early in the sequence of brain division) make a lot of connections to other neurons and a lot of mistakes, which they then correct by repositioning or removing their axons. By contrast, later RGCs were observed to be highly accurate in their target selection skills and made almost no errors.
“The neurons are paying attention to when they were born and reading out which choices they should make based on their birthdate,” said Jessica Osterhout, a doctoral student in biology and the study’s lead author. “It seems to all boil down to birthdate.”
The idea that timing is important for cell differentiation is a classic principle of developmental biology, but this study is among the first to show that the timing of neuronal generation is linked to how neurons achieve specific brain wiring.
In addition to clarifying normal brain development, researchers plan to examine the role of time-dependent wiring mishaps in models of human disorders, such as autism and schizophrenia, as well as diseases specific to the visual system, such as congenital blindness.
“We want to know if in diseases such as autism neurons are made out of order and as a result get confused about which connections to make,” Huberman said.
Co-authors include Rana El-Danaf and Phong Nguyen, both at UC San Diego.
Funding for the study was provided, in part, by the National Institutes of Health’s National Eye Institute (grant R01-EY022157), The E. Matilda Ziegler Foundation for the Blind, Inc. and, The Pew Charitable Trusts.
Back tomorrow. Jeanne