Research Roundup

Anger and anxiety: Two sides of the same coin?

Anger and anxietyAnger and anxiety are closely intertwined for people with generalized anxiety disorder (GAD), according to research published by Sonya Deschênes, a graduate student in experimental psychology at Concordia University, and her colleagues. In a study published in Cognitive Behavior Therapy last year, Deschênes found that anger is related to more pronounced symptoms of GAD.

The findings stem from an observation made by her supervisor, who noticed a pattern of anger manifesting itself in many of his patients. In her doctoral research, Deschênes noticed that research often identified correlations between anger and anxiety. But little seemed to be known about how anger's various forms contribute to the anxiety disorder.

They pulled together a team to assess 380 undergrads, asking them to list the things they worry about and rate how heavily those worries interfere with their lives — endorsing statements such as, "I am always worrying about something." The participants also reported how much they agreed with such statements as, "I get angry when I'm slowed down by others' mistakes."

Unlike non-anxious participants, those with GAD symptoms reported high levels of anger that they mostly kept bottled up, Deschênes found.

"A lot of research suggests that individuals with GAD have an ‘allergy to uncertainty,'" says Deschênes. This "allergy" may lead to anger as well as excessive worry, the main diagnostic criteria of GAD, she explains.

To further elucidate the link between the two emotions, Deschênes and her colleagues are now purposely antagonizing experiment participants to see if anger makes it more difficult for them to tolerate uncertainty. She will also explore whether induced anger intensifies interpretation bias — the tendency to assume the worst when confronted with ambiguous situations — and the extent to which participants worry.

Although this tendency may interfere with cognitive-behavioral therapy for patients with GAD, Deschênes says it's too early to make clinical recommendations. But, she adds, "it would be worthwhile for students doing anxiety research to start incorporating anger measures into their studies."

—Lindsay Abrams

What came first, the concept or the name?

Naming categories doesn't necessarily help people use them, according to research published last year in the Journal of Experimental Psychology.

What came first, the concept or the name?People tend to be faster at distinguishing between two things in different categories than between things in the same category. For example, people can usually realize a plate and a cup are different faster than they can distinguish between two similar plates. And people are even faster at this kind of task when they view the objects with their right eyes, linking to the left hemisphere of their brains — where language is processed.

To test whether language really does play a role, Emory University cognition and development grad student Kevin Holmes and his colleagues showed adult participants random shapes grouped into categories. One group of participants was taught names for the categories, the other group was not.

Each participant then viewed a set of shapes they had learned, arranged in a ring. One shape in the ring was different from the others. Participants were faster to locate the different one when it was in a different category than the other shapes, but only when it was shown in the right visual field and hence was processed by the left hemisphere. But both groups were equally adept at the task, regardless of whether they had learned category names.

The finding shows that while categorization appears highly dependent on the left hemisphere, language processes don't play a major role, Holmes says. That's not to say that language plays no role in categorization, he adds. Past researchers have found that Russian speakers, who consider light blue and dark blue to be distinct colors and call them different names, distinguish between the two faster than English speakers do.

"Many of the categories we have, we wouldn't have formed if language hadn't told us to form them," Holmes says. But it appears that categories affect our thinking independently, whether they have linguistic labels or not.

—Kim Kreiger

Study explores the neural underpinnings of motion perception

The brain uses at least two different areas to perceive human motion — one area seems to broadly identify movement as biological in origin, while the other decides whether the movement is human, according to research by neuroscience graduate student Bianca Michelle van Kemenade published in the April issue of the Journal of Cognitive Neuroscience.

Van Kemenade and her colleagues at University College London used transcranial magnetic stimulation to temporarily disable participants' premotor cortex, located behind the forehead, or superior temporal sulchus, located around the side of the head in the middle of the brain. Participants also received transcranial magnetic stimulation to the top of their heads as a control. The participants then viewed displays of human movement with dots representing the major joints in the human body.

As soon as the dots began to move, the control participants easily identified whether they represented a person. However, the participants with their premotor cortex disabled gave significantly more false positives, while the participants with their superior temporal sulchus disabled saw their sensitivity to human motion decline more generally.

"The superior temporal sulchus may be responsible for perceiving biological motion ... and the premotor cortex has more to do with decision-making" — in this case, determining whether the dots represented a person, van Kemenade says. The difference may hinge on the fact that the premotor cortex is part of the mirror-neural network, which activates in humans when they watch others move. Disabling the premotor cortex may deprive people of their ability to use the mirror-neurons to mentally map movements onto their own bodies and understand what someone else is doing, she says.

—Kim Kreiger

Toddlers are careful about ledges, but not tight spots

Babies cautiously avoid situations in which they might fall, but they don't seem to recognize the danger in getting stuck, according to a study by John Franchak in the September issue of Developmental Psychology.

Toddlers are careful about ledges, but not tight spots.Franchak, a New York University cognition and perception student, and his colleagues had 17-month-olds stroll down a walkway to reach their mothers. Half of the 32 babies navigated a doorway, while the other half navigated a ledge. Each baby took the test 30 to 40 times, with the width of the doorway or ledge narrowing, eventually getting so small that the baby would get stuck or fall. No babies were injured during the course of the research — Franchak or a colleague caught the babies who fell, and the door was easily slid open to extricate any baby who got stuck. The researchers noted the widths at which each baby attempted and refused to navigate the obstacle.

Only 11 of the 16 babies fell during the precipice trials, but every single baby who participated in the doorway tests eventually got stuck.

This oversight wasn't from lack of experience: 70 percent of the babies had previously wedged their hands, head or entire bodies in tight spots, their parents said.

"We concluded that infants just don't care as much about getting stuck," Franchak says. Perhaps the infants believe falling carries a much greater risk of injury than entrapment, he posits. However, infants do realize when an opening is getting close to too small for them to easily navigate. They turned their bodies when approaching a narrow opening, showing they understood the opening was small and that they would have to maneuver carefully.

—Kim Kreiger