Research Roundup

  • Even modest financial incentives can improve exercise commitment and effortEven modest financial incentives can improve exercise commitment and effort, according to a meta-analysis led by Marc Mitchell, a doctoral student at the University of Toronto. The researchers examined 11 randomized controlled exercise trials with nearly 1,500 adults. They found that providing financial incentives — such as cash or gift vouchers — led to a nearly 12 percent average increase in exercise session participation. They also found that guaranteed incentives were more successful than lottery-type incentives. Although the largest incentives were associated with the greatest effects, even incentives as small as $2.79 per session were effective (American Journal of Preventive Medicine, September [PDF, 277KB]).

  • Sleep deprivation affects the eyes, mouth, skin and other facial features, cuing others in to a person's sleep loss, finds research led by Tina Sundelin, a psychology doctoral student at Stockholm University. The scientists photographed 10 study participants after eight hours of normal sleep and after 31 hours of sleep deprivation. Then they asked 40 participants to rate the photographs with respect to 10 facial cues for fatigue and sadness. Participants perceived the faces of the sleep-deprived individuals as having more hanging eyelids, redder and more swollen eyes, darker under-eye circles, paler skin, more wrinkles and more droopy corners of the mouth. People also looked sadder when sleep-deprived than after normal sleep (Sleep, September).

  • A person's ability to delay gratification may depend on how trustworthy the person perceives the reward-giver to be, according to a study led by Laura Michaelson, a psychology doctoral student at the University of Colorado Boulder. The researchers asked study participants to read profiles of three fictional people and then rate them on their trustworthiness. They then asked participants whether they would opt to take a smaller amount of money offered immediately from each person or a larger amount that they would have to wait to collect. The participants were more likely to delay gratification when they trusted the person who was offering the reward. A second experiment — which relied on a larger group but involved each participant's reading the profile of only one character — showed similar results (Frontiers in Psychology, online June 19).

  • Women who were abused as children are more likely to be obese as adults, according to research co-authored by University of Toronto doctoral student Deborah Sinclair. The scientists analyzed data from more than 12,500 Canadian adults and found that, after adjusting for age and race, childhood physical abuse was associated with 47 percent higher odds of obesity for women compared with women from nonabusive homes. Among men, however, obesity wasn't associated with childhood physical abuse (Obesity Facts, online Aug. 10 [PDF, 1.3MB]).

  • Frequent nights apart negatively affect mother-child attachmentFrequent nights apart negatively affect mother-child attachment, according to a study led by Samantha Tornello, a psychology graduate student at the University of Virginia. The researchers analyzed interviews and in-home assessment data with the parents of about 5,000 children born in large U.S. cities from 1998 to 2000. They found that infants who spent one or more nights a week away from their mothers — at the homes of their fathers due to break-up, separation or divorce, for example — had more insecure maternal attachments than babies who had fewer overnights away or saw their fathers only during the day (Journal of Marriage and Family, August).

  • Human imagination lies in the brain's "mental workspace" — a widespread neural network that coordinates activity across several regions in the brain and consciously manipulates symbols, images, ideas and theories, finds research led by Alexander Schlegel, a psychology graduate student at Dartmouth College. The scientists used fMRI to measure the brain activity of 15 volunteers while they thought about specific visual shapes and then mentally combined them into more complicated figures. The researchers also asked the participants to create complex images in their minds and then mentally dismantle them. They found that the brain's visual cortex — as expected — was actively involved in driving mental manipulation, but they also discovered that the occipital, frontoparietal, posterior parietal and several other regions also appeared to be involved in manipulating imaginary shapes (Proceedings of the National Academy of Sciences, online Sept. 16).

  • People prefer products that help them "save face" in embarrassing moments, finds research led by Ping Dong, a doctoral student at the University of Toronto. In one experiment, the scientists asked one group of participants to describe an embarrassing situation from their past, and asked another group to describe a typical day at school. Later, all participants rated various pairs of sunglasses. They found that participants who relived their embarrassing experiences tended to prefer large, dark-tinted sunglasses. In another experiment, embarrassed participants expressed more interest in sunglasses and restorative face creams — products that would conceal or cover their faces — than in scarves or shoes (Psychological Science, online Aug. 12).