Research Roundup |
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March 24, 2015, Volume 61, No. 27 |
A Simple Intervention Can Make Your Brain More Receptive to Health Advice
Tongue Fat and Size May Predict Sleep Apnea
Penn Astronomers’ Hunt for Dark Energy
A Simple Intervention Can Make Your Brain More Receptive to Health Advice
“Self-affirmation involves reflecting on core values,” explained Emily Falk, the study’s lead author and director of the Communication Neuroscience Laboratory at the University of Pennsylvania’s Annenberg School for Communication. Has your doctor ever told you to get more exercise? Has your spouse ever suggested you eat healthier? Even though the advice comes from good intentions, most people feel defensive when confronted with suggestions that point out their weaknesses. Reflecting on values that bring us meaning can help people see otherwise threatening messages as valuable and self-relevant. “Our work shows that when people are affirmed, their brains process subsequent messages differently.”
Along with colleagues at Annenberg, The University of Michigan and The University of California, Los Angeles, Dr. Falk and her team used functional magnetic resonance imaging (fMRI) to examine a part of the brain involved in processing self-relevance called ventromedial prefrontal cortex (VMPFC). The team examined activity in this region as sedentary adults were given the type of advice they might get from a doctor. Participants who were guided through a self-affirmation exercise before receiving the health advice showed higher levels of activity in this key brain region during the health advice and then went on to show a steeper decline in couch-potato-type sedentary behaviors in the month following the intervention. Those who were instructed to think about values that weren’t as important to them showed lower levels of activity in the key brain region during exposure to the health advice and maintained their original levels of sedentary behavior. The results were reported in the Early Edition of the Proceedings of the National Academy of Science the week of February 2.
Past studies have shown that brain activity in VMPFC during health messages can predict behavior change better than individuals’ own intentions, and this study sheds new light on why. VMPFC is the brain region most commonly activated when participants think about themselves and when they ascribe value to ideas. The new results show that opening the brain in this way is a key pathway to behavior change. “Understanding the brain opens the door to new health interventions that target this same pathway,” Dr. Falk noted.
“We were particularly interested in using self-affirmation to help people become more active because sedentary behavior is one of the biggest health threats faced by both Americans and people around the world,” said Dr. Falk. Overly sedentary lifestyles are becoming a big problem; in some regions nearly 85 percent of adults lead an inactive lifestyle. This can cause multiple health problems, including poor heart health, diabetes and cancer. Increasing activity even in small amounts can have an important impact on both mental and physical health.
The team studied 67 sedentary adults from a range of backgrounds. Participants wore devices on their wrists to objectively measure their activity levels for a week before and a month after the intervention. Participants were also sent text messages reinforcing the main messages delivered in the fMRI scanner. Volunteers were shown health messages such as, “According to the American Heart Association, people at your level of physical inactivity are at much higher risk for developing heart disease,” or “After an hour of sitting, try standing for five minutes. Stand up while you read, watch TV, talk on the phone, fold laundry or write an email.” For some participants, these health messages were packaged with a self-affirmation message like “Think of a time when you will help a friend or family member reach an accomplishment.” When health messages were paired with self-affirmation, volunteers demonstrated more activity in VMPFC activity during the health message and also went on to follow the advice more.
Psychologists have used self-affirmation as a technique to improve outcomes ranging from health behaviors in high-risk patients to increasing academic performance in at-risk youth, suggesting that the findings may be applicable across a wide range of interventions. “Our findings highlight that something as simple as reflecting on core values can fundamentally change the way our brains respond to the kinds of messages we encounter every day,” Dr. Falk noted. “Over time, that makes the potential impact huge.”
Tongue Fat and Size May Predict Sleep Apnea
Obesity is a risk factor for many health problems, but a new Penn Medicine study published this month in the journal Sleep suggests having a larger tongue with increased levels of fat may be a sign of obstructive sleep apnea (OSA) in obese adults. The researchers examined tongue fat in 31 obese adults who had OSA and 90 obese adults without the condition. All subjects underwent magnetic resonance imaging and the size and distribution of upper airway fat deposits in their tongue and upper airway muscles were measured.
“Previous studies showed that the human tongue has a high percentage of fat, and that tongue fat and tongue weight were positively correlated with the degree of obesity,” said study senior author Richard J. Schwab, professor of medicine in Penn’s Perelman School of Medicine and member of the Center for Sleep and Circadian Neurobiology. “This is the first study that examined OSA patients and found higher fat deposits in obstructive sleep apnea patients than in those without OSA.” The data also showed a correlation between tongue fat volume and sleep apnea severity, and with body mass index. The researchers believe that increased tongue fat may explain the pathogenic relationship between obesity and sleep apnea.
Adults with a body mass index of 30 or higher are considered obese. The latest Centers for Disease Control and Prevention survey of nationally representative data in 2011 and 2012 reported that nearly 35 percent of US adults – 78.6 million people – are obese. OSA affects more than 15 million adult Americans. The number of OSA cases is rising, mirroring the increasing weight of the average individual. Although obesity is the strongest risk factor for development of OSA, the ways that obesity confers risk for OSA are unknown. The researchers believe the increase in fat not only increases tongue size, but also decreases tongue force and hinders the tongue from properly functioning as an upper airway dilator muscle, which can lead to apneas during sleep.
Penn Astronomers’ Hunt for Dark Energy
After more than a decade of development and planning, the National Science Foundation has approved federal construction of the Large Synoptic Survey Telescope (LSST). The Association of Universities for Research in Astronomy, of which the University of Pennsylvania is a member, will manage the $473 million construction project.
The LSST will be constructed atop Cerro Pachón, a mountain in Chile’s Atacama Desert, one of the highest, driest locations in the world. It will see first light in 2019 and begin full science operations in 2022.
Gary Bernstein, Larry Gladney, Bhuvnesh Jain, Mike Jarvis and Masao Sako of the department of physics & astronomy in the School of Arts & Sciences are involved in LSST. Dr. Jain leads LSST’s cosmology effort as spokesperson for its Dark Energy Science Collaboration, while Dr. Jarvis is co-coordinator of its weak gravitational lensing working group.
Gravitational lensing involves measuring minute distortions in the light of distant galaxies as a way of inferring the properties of objects that light passes on its way to Earth. These objects include galaxies and cosmic superclusters, which are dominated by dark matter, a form of matter that is not directly visible. Lensing is also one of the main methods Drs. Bernstein, Jain and Jarvis are applying with the ongoing Dark Energy Survey. This survey is designed to explore dark matter as well as dark energy, the mysterious force that may be responsible for the accelerating expansion of the universe.
The LSST’s mission will expand upon the Dark Energy Survey’s capabilities, imaging about ten times as many galaxies, each in greater detail.
“LSST will be able to detect galaxies two to three times further than the Dark Energy Survey telescope,” Dr. Jain said, “and it will cover about four times as much sky. Over the LSST’s 10-year survey, it will take about 800 exposures of each of three billion galaxies. With this detailed information on galaxies most of the way to the edge of the observable universe, we will carry out a wide range of cosmological studies.”
“One of the other advantages of the LSST,” Dr. Bernstein said, “is that it is a ‘time domain’ survey. It will catch the variability of stars, environments of black holes, supernovae, asteroids—all kinds of objects from inside the solar system to distant galaxies—over timescales that range from a few hours to a year.”
The data collected by the survey—a petabyte-scale database of astronomical images—will be made publically available in an effort to promote open research as well as science, technology, engineering and mathematics education.
Though federal funding has just been approved, fabrication of the major mirror components for LSST is already underway, thanks to private funding received from the Charles and Lisa Simonyi Foundation for Arts & Sciences, Bill Gates and others. Receipt of federal construction funds allows major contracts to move forward, including those to build the telescope mount assembly, the figuring of the secondary mirror, the summit facility construction, the focal plane sensors and the camera lenses.
“This agreement,” said Victor Krabbendam, LSST’s project manager, “is a tribute to the hard work of an exceptional team of highly skilled individuals, many of whom have dedicated more than a decade to bringing LSST to this point. After a rigorous design and development phase, the project team is ready to get down and dirty and actually build this amazing facility.”
The LSST camera fabrication budget, funded by the US Department of Energy, will be settled later this year but is estimated at $165 million. Operations costs are estimated at $37 million per year for the ten-year survey.
LSST project activities are supported through a partnership between the National Science Foundation and the US Department of Energy. The NSF supports LSST through a cooperative agreement managed by AURA. The US Department of Energy-funded effort is managed by the SLAC National Accelerator Laboratory. Additional LSST funding comes from private donations, grants to universities and in-kind support from institutional members of the LSST Corporation, a non-profit entity with headquarters in Tucson, Arizona. |