Study shows decision-making in real time
COLUMBUS – It takes just a few seconds to choose a cookie over an apple and wreck your diet for the day.
But what is happening during those few seconds while you make the decision?
In a new study, researchers watched in real time as people’s hands revealed the struggle they were under to choose the long-term goal over short-term temptation. The work represents a new approach to studying self-control.
In one key experiment, participants viewed pictures of a healthy and an unhealthy food choice on opposite sides of the top of a computer screen and moved a cursor from the center bottom to select one of the foods.
People who moved the cursor closer to the unhealthy treat (even when they ultimately made the healthy choice) later showed less self-control than did those who made a more direct path to the healthy snack.
“Our hand movements reveal the process of exercising self-control,” said Paul Stillman, co-author of the study and postdoctoral researcher in psychology at The Ohio State University.
“You can see the struggle as it happens. For those with low self-control, the temptation is actually drawing their hand closer to the less-healthy choice.”
The results may shed light on a scholarly debate about what’s happening in the brain when humans harness willpower.
Stillman conducted the study with Melissa Ferguson, professor of psychology, and Danila Medvedev, a former undergraduate student, both from Cornell University. Their research will appear in the journal Psychological Science.
The study involved several experiments. In one, 81 college students made 100 decisions involving healthy versus unhealthy food choices.
In each trial, they clicked a “Start” button at the bottom of the screen. As soon as they did, two images appeared in the upper-left and upper-right corners of the screen, one a healthy food (such as Brussels sprouts) and the other an unhealthy one (such as a brownie).
They were told to choose as quickly as possible which of the two foods would most help them meet their health and fitness goals. So there was a “correct” answer, even if they were tempted by a less healthy treat.
Before the experiment began, the participants were told that after they finished they would be given one of the foods they chose in the experiment. At the end, however, they could freely choose whether they wanted an apple or a candy bar.
The results showed that those who chose the candy bar at the end of the experiment – those with lower self-control – had tended to veer closer to the unhealthy foods on the screen.
“The more they were pulled toward the temptation on the computer screen, the more they actually chose the temptations and failed at self-control,” Stillman said.
But for those with higher levels of self-control, the path to the healthy food was more direct, indicating that they experienced less conflict.
In two other studies, similar results occurred in a completely different scenario, in which college students could decide whether they would rather accept $25 today or $45 in 180 days. Those with lower levels of self-control had mouse trajectories that were clearly different from those with higher self-control, suggesting differences in how they were dealing with the decisions.
“This mouse-tracking metric could be a powerful new tool to investigate real-time conflict when people have to make decisions related to self-control,” he said.
The findings also offer new evidence in a debate about how decision-making in self-control situations unfolds, Stillman said.
When the researchers mapped the trajectories people took with the cursor in the first experiment, they observed that most participants did not automatically start directly toward the unhealthy treat before abruptly switching course back to the healthy food. Rather, the trajectories appear curved, as if both the temptation and goal were competing from the beginning.
Why is that important?
Some researchers have argued that there are two systems in our brain that are involved in a self-control decision: one that’s impulsive and a second that overcomes the impulses to exert willpower. But if that were the case, the trajectories seen in this study should look different than they do, Stillman said.
If dual systems underlie these choices, there should be a relatively straight line toward the unhealthy food while people are under the influence of the impulsive first system and then an abrupt change in direction toward the healthy food as the system in charge of self-control kicks in.
“That’s not what we found,” Stillman said. “Our results suggest a more dynamical process in which the healthy and unhealthy choices are competing from the very beginning in our brains and there isn’t an abrupt change in thinking. That’s why we get these curved trajectories.”
Stillman said these results should help lead to a more accurate view of how our cognitive processes unfold to allow us to resist temptation.
Scientists make “squarest” ice crystals ever
You won’t find ice cubes like this in your freezer.
An international team of scientists has set a new record for creating ice crystals that have a near-perfect cubic arrangement of water molecules—a form of ice that may exist in the coldest high-altitude clouds but is extremely hard to make on Earth.
The ability to make and study cubic ice in the laboratory could improve computer models of how clouds interact with sunlight and the atmosphere—two keys to understanding climate change, said Barbara Wyslouzil, project leader and professor of chemical and biomolecular engineering at The Ohio State University.
It could also enhance our understanding of water – one of the most important molecules for life on our planet.
Seen under a microscope, normal water ice—everything from frozen ponds, to snow, to the ice we make at home—is made of crystals with hexagonal symmetry, Wyslouzil explained. But with only a slight change in how the water molecules are arranged in ice, the crystals can take on a cubic form.
So far, researchers have used the presence of cold cubic ice clouds high above the earth’s surface to explain interesting halos observed around the sun, as well as the presence of triangular ice crystals in the atmosphere. Scientists have struggled for decades to make cubic ice in the laboratory, but because the cubic form is unstable, the closest anyone has come is to make hybrid crystals that are around 70 percent cubic, 30 percent hexagonal.
In a paper published in the Journal of Physical Chemistry Letters, Wyslouzil, graduate research associate Andrew Amaya and their collaborators describe how they were able to create frozen water droplets that were nearly 80 percent cubic.
“While 80 percent might not sound ‘near perfect,’ most researchers no longer believe that 100 percent pure cubic ice is attainable in the lab or in nature,” she said. “So the question is, how cubic can we make it with current technology? Previous experiments and computer simulations observed ice that is about 75 percent cubic, but we’ve exceeded that.”
To make the highly cubic ice, the researchers drew nitrogen and water vapor through nozzles at supersonic speeds. When the gas expanded, it cooled and formed droplets a hundred thousand times smaller than the average raindrop. These droplets were highly supercooled, meaning that they were liquid well below the usual freezing temperature of 32 degrees Fahrenheit (0 degrees Celsius). In fact, the droplets remained liquid until about -55 degrees Fahrenheit (around -48 degrees Celsius) and then froze in about one millionth of a second.
To measure the cubicity of the ice formed in the nozzle, researchers performed X-ray diffraction experiments at the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory in Menlo Park, CA. There, they hit the droplets with the high-intensity X-ray laser from LCLS and recorded the diffraction pattern on an X-ray camera. They saw concentric rings at wavelengths and intensities that indicated the crystals were around 80 percent cubic.
The extremely low temperatures and rapid freezing were crucial to forming cubic ice, Wyslouzil said: “Since liquid water drops in high-altitude clouds are typically supercooled, there is a good chance for cubic ice to form there.”
Exactly why it was possible to make crystals with around 80 percent cubicity is currently unknown. But, then again, exactly how water freezes on the molecular level is also unknown.
“When water freezes slowly, we can think of ice as being built from water molecules the way you build a brick wall, one brick on top of the other,” said Claudiu Stan, a research associate at the Stanford PULSE Institute at SLAC and partner in the project. “But freezing in high-altitude clouds happens too fast for that to be the case—instead, freezing might be thought as starting from a disordered pile of bricks that hastily rearranges itself to form a brick wall, possibly containing defects or having an unusual arrangement. This kind of crystal-making process is so fast and complex that we need sophisticated equipment just to begin to see what is happening. Our research is motivated by the idea that in the future we can develop experiments that will let us see crystals as they form.”
Additional co-authors on the paper were from Ohio State, SLAC, the National University of Singapore, Stockholm University, KTH Royal Institute of Technology, Brookhaven National Laboratory and the National Science Foundation BioXFEL Science and Technology Center. The research was funded by the National Science Foundation, the U.S. Department of Energy and SLAC. The use of LCLS was supported by the U.S. Department of Energy Office of Science.
Ohio State trustees approve tuition and fees, new guarantee
The Board of Trustees has approved new tuition and fees for the 2017-18 academic year and enacted the Ohio State Tuition Guarantee. In-state tuition and mandatory fees will increase 5.5 percent for incoming freshmen on the Columbus campus and, under the guarantee, be frozen at that level for four years.
When the program begins this fall, it will apply to new incoming freshman only. Tuition and fees will not increase for existing, in-state students — including sophomores, juniors and seniors — enrolled on all campuses. It is the fifth straight year that in-state tuition and fees have been frozen for existing students.
The board also approved a 6 percent increase in housing and a 3 percent increase in dining. For incoming freshmen, the guarantee program will freeze both for four years.
Increasing the value of the Land Grant Opportunity Scholarship program to cover the full cost of attendance. The university will also double the size of the scholarship program next year, making the scholarship available to two students from each Ohio county per year — a total of 176 scholarships.
Committing $25 million to the President’s Affordability Grant Program. Entering its third year, the program will have provided a total of $60 million to middle- and lower-income Ohio undergraduates — bringing the university closer to its stated goal of $100 million in additional need-based aid by 2020. The grants are funded through Ohio State’s administrative efficiency program.
Current students will continue to pay $10,037 for in-state tuition and mandatory fees at the Columbus campus. For incoming first-year students on the Columbus campus, the Ohio State Tuition Guarantee sets resident tuition and fees at $10,591 per year through 2020-21. The tuition guarantee is set at $7,553 for the Lima, Mansfield, Marion and Newark campuses and $7,517 at the Agricultural Technical Institute in Wooster.
The university offers a variety of housing and dining plans. The most common undergraduate plans on the Columbus campus will total $6,126 per semesters.
Trustees also approved:
New housing and dining plans for the Newark campus; increasing student health insurance by 8.7 percent; and adjusting eight market-based differential fees for master’s and professional programs in individual colleges.
Increasing the non-resident surcharge for undergraduates and most graduate students by 5 percent and increasing the international surcharge by $996 per year for new international students.
Continuing the tuition waiver for Ohio State students enrolled in university-approved Third Party Provider/Direct Enroll Study Abroad Programs for fiscal years 2018 and 2019.
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