Research Roundup

New research offers clues on why we splurge

Going shopping? You're likely to overspend if you think of the expense as exceptional, according to a study in press in the Journal of Consumer Research.

Why do we splurge?Abigail Sussman, a doctoral candidate in psychology and social policy at Princeton, and Adam Alter, PhD, a professor at the New York University School of Business, challenged college students to predict the cost of unusual, one-time expenses they'd have in the coming week, such as replacing a TV, or dinner out to celebrate a special occasion. A week later, the students reported that they spent nearly double what they'd predicted.

In a follow-up experiment, the researchers asked participants how much they would spend on various exceptional purchases, and they reported they would spend more when items were presented one at a time on the screen rather than all together, as a group. Another experiment primed participants to think of items as being part of either small or large categories — for example, home electronics versus household items — and found that the participants spent less when they had the larger contexts in mind.

The findings suggest we budget better when we categorize an expense broadly and consider a lengthy time frame. So, next time you're shopping for a gift, "Consider how many times this year you'll need to purchase presents — not only for birthdays, but for holidays and other special occasions as well," Sussman suggests.

Insight into the underpinnings of learning

How do neurons form new connections to one another? A new study by Travis Hill, at the University of California, Davis, in press in the Journal of Neuroscience, provides evidence that at least some learning relies on the process known as "long-term potentiation" (LTP), in which two neurons that repeatedly fire in unison become more strongly linked.

Other researchers have reported "spines" — the plug-in-port for axons — sticking around as animals learned a task. To see if he could make the same thing happen using LTP, Hill bathed slices of living rat hippocampi in a form of the neurotransmitter glutamate that he could release using laser pulses delivered through a two-photon microscope. Then, he released the neurotransmitter around one of its newly formed spines, mimicking the arrival of an impulse from another cell. This process, by itself, did not induce a spine to stick around, and neither did changing the charge of a neuron's membrane. But when Hill combined them, the lucky new spine stuck around. 

While the result is far from the first to link LTP and learning, it furthers scientists' understanding of the inner working of learning in the brain. "The most exciting aspect of my work is that I was able to arbitrarily select which synaptic elements should be stabilized – this could potentially allow us to wire neurons one synapse at a time," Hill says.

Girls with ADHD make realistic self-appraisals, research finds

Researchers have reported that children with attention-deficit hyperactivity disorder (ADHD) believe they are coping better socially and in school than they actually are, but Erika Swanson, PhD, a recent graduate from the University of California at Berkeley's clinical psychology program, has found this to be untrue in girls.

In a study published in August in the Journal of Abnormal Child Psychology, Swanson drew data from a cohort of 140 girls with ADHD and 88 girls whom did not have the disorder, who researchers followed from ages 6 to 18. In addition to obtaining standardized test scores, they asked the girls to rate their own academic performance, classroom conduct and social skills. The researchers also questioned teachers, parents and peers about the students' academic performance, classroom conduct and social skills.

Swanson found that the girls with ADHD assessed themselves as realistically as peer report and standardized test scores did. However, parents and teachers scored the ADHD girls significantly lower than girls' self-report in the social, academic and behavioral domains. These discrepancies, however, didn't seem to lead to poorer functioning for girls with ADHD later in adolescence, Swanson found.

"It's not that girls with ADHD aren't struggling in these areas," Swanson says. "However, we shouldn't be so concerned with how these kids think they're doing and should work on actual skill building."

Children and adults agree: Our eyes are the seat of the self

Ask a preschooler where the self lives, and he's likely to say the eyesDescartes proposed the pineal gland; Aristotle thought the heart. But ask a preschooler where the self lives, and he's likely to say the eyes, according to a study in the May issue of Cognition.

Yale developmental psychology graduate student Christina Starmans showed 4- and 5-year-olds and adults 30 pairs of cartoons in which a fly or a snowflake hovered close to a character's body at some level above the ground. She then asked which cartoon showed the object hovering closer to the character. Both the children and adults tended to choose the pictures where the fly or snowflake hovered near the character's eyes rather than the chest, mouth or other parts, even though the distance from the character's body was always the same. This effect even held when the cartoon character was a green alien boy with eyes on his chest.

The results suggest that many people have the feeling that the self is centered behind the eyes. This sense seems to originate in childhood and may even be innate, says Starmans.

Oliver Baker is a writer in Portland, Ore.