Category: Behavior/Psychology Page 27 of 28

Learning to Fear, By General Category

On December 16, 2011

Guest post by graduate student Kia Walcott

If an animal is lucky enough to escape a predator, that animal will not only avoid the predator but it will have learned to avoid other animals that resemble it in the future. Survivors learn what can eat or hurt them and label them as harmful.

An example of the equipment used in this experiment

Duke neuroscientists Joseph Dunsmoor and Kevin LaBar and NIH neuroscientist Alex Martin wanted to see if we too can learn to fear and avoid related threats.

The researchers showed 26 healthy volunteers an assortment of images belonging to two categories: tools or animals. Some of the images associated with a particular category came along with an “annoying but not painful” electrical shock. They saw 20 images during four training sessions. The images included typical objects such as a dog or hammer as well as more atypical objects such as an auger (a fancy type of drill) or a leaf insect. The participants saw each image for six seconds, during which time they rated their shock expectancy. Researchers also measured the subjects’ sweat rate, which links to their emotional arousal as a result of fear.

The participants returned 24 hours after the last session for a surprise memory test which included the 80 total images (20 images over four training sessions) as well as 40 new images (20 tools and 20 animals), and were asked to rate whether each image was new or old and their level of confidence. The test was to see if participants were more likely to remember objects belonging to the shock category versus the ‘safe’ category.

By relating an object to a broader category, the participants quickly and effectively determined which group of objects was associated with the shock. A difference in sweat rate was also seen in response to objects in the shock category versus those in the non-shock category. Participants were more likely to remember items from the shock category than items from the non-shock category.

These results suggest that fear can be learned and remembered by categories. In the future, the researchers would like to use brain imaging to see how areas of the brain important for visual object recognition and conceptual knowledge interact with areas important for associating harmful and harmless things. Another important question is how learned fear and memory interact, especially in the case of traumatic experiences.

People who are unable to make connections between known threats and conceptually related things might fail to generalize fear properly, which could prove dangerous. On the other hand, people who make too many connections to a known threat could suffer too, as in posttraumatic stress disorder.

Citation: “Role of conceptual knowledge in learning and retention of conditioned fear,” Joseph Dunsmoor, Alex Martin, Kevin LaBar. Biological Psychology, Nov. 2011. doi: 10.1016/j.biopsycho.2011.11.002

http://www.sciencedirect.com/science/article/pii/S03010(2011)51111002730

Is He Conscious? Does He Want To Be?

By Jeannie Chung

On December 13, 2011

In Behavior/Psychology, Lecture, Medicine, Neuroscience

Terri Schiavo of Florida, whose vegetative state and right to life became a national issue in 2005

By Jeannie Chung

The difference between a dead man and a man in a vegetative state used to be a thin line of whether
or not the body was still functioning. But what if the vegetative man is still conscious? That brings
the distinction into a whole new level.

Philosopher Walter Sinnott-Armstrong gave a talk titled “Is he conscious? Does he want to be?” at the Trent Center for Bioethics on Friday, Dec. 9. He discussed clinical studies which have shown that despite the unresponsive display, patients in vegetative state may be still conscious. With assistance from an fMRI or an EEG scan, doctors can tap into the patient’s brain activity and “read their thoughts.”

The scanning study’s control was patients who received severe brain trauma and were confirmed to be in a vegetative state. The studies focused on the specific brain activity when the patient was commanded to “think about tennis” and the brain activity that occurred when the patient was commanded to “imagine anything other than tennis.” The distinctive brain activities were then coupled with a series of yes or no questions. If their answer was yes, the patient was told to think about tennis and if their answer was no, the patient was told to think about navigating through a house. In one case study, the patient answered five out of seven questions right by showing brain activity associated with tennis to questions for which an affirmative was the correct answer. The other two questions showed no response, and the doctors assumed the patient had gone to sleep.

This confirmation of consciousness in some vegetative patients brings up an ethical issue. Those at the bedside can now ask questions, including “do you want to live?” The vegetative patient’s answer to such a question may inform the ethical issue that arises each time we worry about “pulling the plug” on a clearly “living” person.

Sports fans are NOT testosterone-crazed couch potatoes

By Karl Bates

On December 13, 2011

In Behavior/Psychology, Neuroscience

By Karl Leif Bates

A new study out of the Center for Cognitive Neuroscience that compared personality traits and sports-watching habits has found that the Cameron Crazies probably aren’t crazy at all.

Couch Potato contest in Chicago, 2009. Steve Janowski via Wikimedia Commons

As part of a much larger series of studies that gathered psychological and biophysical measures from more than 500 people, Duke psychologists Gregory Appelbaum and Stephen Mitroff looked through the data to see if sports fans were true to their stereotype as slothful shut-ins.

Running a series of regression analyses on a sub-set of 293 participants, they compared self-reported consumption of sporting events with other traits, including hormone levels, exercise frequency, extroversion, and autism.

Bottom line: Sports fans are MORE extroverted and active than non-fans. They are no more likely to have attention deficit disorder or to be hyper-testosteroned.

But they still may be prone to buffalo-wing breath.

CITATION – “What is the identity of a sports spectator?” Gregory Appelbaum, L., et al. Personality and Individual Differences (2011). doi:10.1016/j.paid.2011.10.048

Your brain on memories

By Ashley Yeager

On November 15, 2011

In Behavior/Psychology, Neuroscience, Science Communication & Education, Students, Visualization

By Ashley Yeager

Students map the molecules associated with memory and how they flow through a brain cell. Courtesy of Craig Roberts, Duke.

9/11. JFK’s assassination. A man on the moon.

These words probably evoke a memory of where you were and how you reacted, if you were alive when the events occurred.

The exact molecules and brain processes that form memories and make some memories stronger than others haven’t been worked out yet. But by “walking” through our brain cells, a team of Duke students is taking a more vivid look at how we remember the past.

With Duke computer science faculty, neuroscientist Craig Roberts and his students have created and tested a virtual representation of our brain cells. In this world, students move around a virtual neuron, rearranging and organizing molecules to express their understanding of our memories.

In this 3-D environment of a neuron, students can mock how molecules flow through the brain to make memories. Courtesy of Craig Roberts, Duke.

Working in a shared digital space from individual computers, the students collaborate in both real life and cyberspace to model the flow of molecules from brain cell to brain cell. Computer scientists Julian Lombardi and Mark McCahill designed the neuronal landscape on Open Cobalt, a community-based, open-source web page for developing virtual, 3-D workspaces.

Roberts, the assistant director of education of the Duke Institute for Brain Sciences, says he trying to harness the “eventuality of the Internet,” where we’ll explore ideas and solve scientific problems on media-rich, multi-dimensional websites.

Roberts says he wanted to teach students about learning and memory. But he also wanted to experiment with whether 2-D or 3-D environments affected how different types of learners participated in class and retained what they were supposed to be studying.

He and undergrad student Daniel Wilson assessed the learning types of the students in the neurobiology class and then gauged their reactions to the 3-D environment compared to the 2-D work done in a collaborative Google document.

A 2-D Google doc mapping molecule movements for making memories. Courtesy of Craig Roberts, Duke.

“We’re finding that active learners perceive greater benefit from the 2-D environment than reflective learners. Visual learners perceive greater benefit than verbal learners from the 3-D environment,” Robert says. He presented the 3-D neuronal environment, his research results and other learning media he has been experimenting with at the 2011 Society for Neuroscience meeting in Washington D.C. on Sat. Nov. 12

By developing different environments in which students can learn, teachers may be able to engage all their students, independent of learning style, Roberts says.

He also said he “sees it as icing on the cake” that in a neurobiology course on learning and memory, students are working in a “learner-centric,” non-lecturing environment to expand their understanding of how they remember and recall the past.

Being The Shy Kid May Have Its Benefits

By Guest Post

On November 14, 2011

In Animals, Behavior/Psychology

Guest post by graduate student Kia Walcott

In a culture that seems to value outgoing personalities, the quiet kid in the corner may have the upper hand.

Since our lineage moved away from other primates, the human personality has evolved in a way that affects a broad range of behaviors. A study conducted by Duke anthropologist Brian Hare and psychologist Esther Herrmann at the Max Planck Institute of Evolutionary Anthropology compared the reaction of our closest ape relatives, the chimpanzee and the bonobo, to the reaction of human infants age 2.5 years to unfamiliar objects and people. (Orangutans were also included in this study as an ‘outgroup’.)

The ape family tree, decorated with adorable babies. (image adapted from http://phylogenous.files.wordpress.com/2011/01/treea.png

Test subjects were presented with items from three categories: human, object, and food. The items within each category varied in familiarity (human: stranger vs. non-stranger), newness and excitement (objects: boring, bland toy vs. loud, exciting toy) and preference (food: delicious vs. not so delicious). The items were presented differently over a period of three days. On day one, the items were only visible, on the second day the items were moved, and on day three the items could be touched. The attraction to or avoidance of the unfamiliar objects was used to measure the test subject’s shyness or boldness.

Human children avoided unfamiliarity and thus most closely resembled the behavior of bonobos, though these apes did not seem to show either avoidance or attraction to the unfamiliar items. Chimpanzees and orangutans approached unfamiliar food and objects more quickly.

The differences seen across species may help explain the development of how we as humans think and react in social situations. For example, a shyer child may be more likely to seek reassurance from parents and peers, which in turn provides an opportunity for social learning and teaching that is unique to humans.

The results of this study also suggest that differences in ecology or where we live shape responses to uncertainty and risk-taking behaviors. Chimpanzees and orangutans have evolved in more unpredictable feeding environments than humans or bonobos, and Hare believes this may explain why, despite being distantly related, these two species showed a similar attraction to unfamiliarity. Chimpanzees and orangutans may have evolved preferences that favor risk over certainty, especially when food payoffs are involved.

On the other hand, Bonobos evolved in an environment with plentiful resources where competition within the group and male aggression are less common.

Research done on domesticated animals has shown that in an environment where male aggression is less common, there is a decrease in both exploratory behavior and stress in new situations. This may explain why bonobos did not seem to care as much about the items presented.

It seems that a more reserved personality may predict better social interaction and thinking later in life.

Citation: “A comparison of temperament in nonhuman apes and human infants,” Herrmann et al. Developmental Science, Nov. 2011. DOI: 10.1111/j.1467-7687.2011.01082.x

Do we judge ourselves by our covers?

By Becca Bayham

On October 25, 2011

In Behavior/Psychology, Business/Economics, Faculty, Lecture, Neuroscience, Students

By Becca Bayham

After giving a lecture at a major women’s magazine, Dan Ariely was faced with a dilemma — in the shape of a huge Prada duffel bag.

As the behavioral economist walked down the street with the bag (a gift from the magazine), he wondered whether he should display the large Prada logo to passersby or hide it against his side.

He decided to hide the logo, but “I was surprised that I still felt like I was walking around with a Prada bag,” Ariely said. “What if I had Ferrari underwear… would I walk a little faster?”

How do the things we wear affect how we think about ourselves? Ariely explored this question (among others) at a Chautauqua lecture on Oct. 18.

In one of Ariely’s experiments, subjects wore shirts emblazoned with the word “stingy” or “generous.” After wearing the shirts around for awhile, participants completed tasks that evaluated their generosity. Strangely enough, “generous” t-shirt wearers gave more during these tasks than those with the “stingy” shirt on.

The word on a participant’s shirt “kind of penetrated their personality,” Ariely said. Notably, the effect was just as strong when participants wore shirts with the writing on the inside.

“Telling ourselves who we are seems to be a crucial element,” Ariely said.

It’s like giving money to a beggar. Giving money doesn’t instantly make you a better person, but it points out certain qualities in yourself. We learn about ourselves the same way that we learn about other people — by observing our actions.

In another study, women were given designer purses, but some were told that their purses were fake. Then participants played a game where cheating was advantageous.

Everyone started fairly enough, but eventually began to cheat. And once they’d cheated a little bit, they just cheated the rest of the time.

“We call this the ‘what the hell’ effect. Everyone who’s been dieting knows this feeling… I’m not good, so I might as well enjoy,” Ariely said.

Interestingly, women wearing counterfeit goods started cheating a lot earlier. Did having fake bags “penetrate their personality,” just as in the t-shirt experiment?

“What if fashion’s not just about telling other people who we are, but also about telling ourselves who we are?” Ariely said.

Changing American science and engineering education

By Ashley Yeager

On October 20, 2011

In Behavior/Psychology, Environment/Sustainability, Science Communication & Education, Students

Students in India work on a forensics experiment. Image courtesy of Duke TIP.

By Viviane Callier, graduate student in Duke Biology

It’s no secret that primary and secondary education in the U.S. falls behind when compared to many other developed countries.

David Kahler, a recent Ph.D. graduate from Duke’s Environmental Engineering program, has been involved in several education and outreach programs that aim to address this problem.

During his graduate career at Duke, Kahler participated in a National Science Foundation (NSF) Graduate Fellows program, which provides support for graduate students in science, technology, engineering, and mathematics, also known as STEM. The program is called NSF GK-12.

In exchange for funding for their graduate studies, Kahler and other fellows contribute to the science curriculum in local primary and secondary schools from kindergarten through grade 12. Kahler taught science at Rogers-Herr Middle School in Durham.

He also taught for two summers in India, and in Texas, as part of Duke TIP, the Talent Identification Program, which identifies academically gifted students and provides them with intellectually stimulating opportunities.

Through these teaching experiences in different locations and cultures, Kahler observed several factors that affect the quality of education in American schools. One important factor is the training of teachers. Unfortunately, teachers are sometimes expected to teach science without having received an adequate background in the subject.

STEM fellows helped to address this problem by contributing their expertise and by helping to increase the scientific literacy of students and their teachers.

Another issue is that parents in the U.S. are often not involved in their children’s education and do not support the mission of both schools and teachers. As a result, children are not engaged in or committed to their own education. In contrast, Kahler found that in India, children are taught by their parents to value and take responsibility for learning.

Because of this difference in attitude toward education, too many American high school graduates are inadequately prepared for college.

Kahler says that NSF GK-12 has a strong, positive impact to change this because it simultaneously improves the educational experience of students in primary and secondary school and trains graduate students to communicate and teach effectively.

Unfortunately, the NSF GK-12 program is no longer in the NSF budget for 2012.

Science Under the Stars

By Karl Bates

On October 6, 2011

In Behavior/Psychology, Biology, Cancer, Chemistry, Climate/Global Change, Computers/Technology, Engineering, Environment/Sustainability, Genetics/Genomics, Physics, Science Communication & Education, Students

Building on earlier successes with K-12 classroom outreach and a huge appearance at the 2010 USA Science and Engineering Festival, Duke University students and faculty are inviting Triangle-area families to join them for an evening of interactive science demonstrations called SCIENCE UNDER THE STARS.

Duke students wowed kids and grownups alike at last year's national science festival in Washington DC.

The October 19 festival will include hands-on, all-ages activities from Chemistry, Physics, Biology, Engineering, Genomics, Environmental Science, Microbiology, Immunology, and Molecular Genetics.

SCIENCE UNDER THE STARS will be from 6 p.m. to 8 p.m. on Wednesday, Oct. 19, on the front lawn of the French Family Science Center on Duke’s West Campus.

At 7:30, the chemists will stage a spectacular grand finale — not quite fireworks, but close!

Free parking is available in the Chemistry parking lot at Research Drive and Towerview, and overflow parking will be available in the Bryan Center structure on Science Drive as well.

RAIN DATE – Thursday, Oct. 20.

For more information contact Kenneth Lyle, PhD at kenneth.lyle@duke.edu

Human brain isn't so special, neurobiologist says

By Ashley Yeager

On September 21, 2011

In Behavior/Psychology, Biology, Lecture, Neuroscience

Mark Changizi argues that speech, writing and music evolved from our brain's interactions with nature.Image courtesy of changizi.com.

By Ashley Yeager

Mark Changizi says there’s no “special sauce” in the human brain. Instead, he argues that our way of thinking is just the brain’s ability to recognize and mimic visual and sound patterns found in nature.

Changizi, an evolutionary neurobiologist and director of Human Cognition at 2ai Labs, spoke about his research during Duke’s first neurohumanities research group seminar on Sept. 20. The group is co-organized by the Franklin Humanities Institute and the Duke Institute for Brain Sciences.

During his talk, Changizi explored with the audience of both scientists and artists his investigations between shapes and sounds, nature and the fundamental elements of speech, music and writing.

He said that our brains didn’t evolve to have language and music instincts. Instead, language and music shaped themselves to be tailored to our brains. Because our brains were cut for nature, language and music mimicked it to transform ape to man.*

Comparing letter structures, with simple opaque, object positions like fallen trees, for example, Changizi explained that there are 36 topological shapes that form the basis for the letters found in 100 different writing systems across the world.

He showed the audience how these different structures could be made by crossing his arms. Most would think that this makes an X, but based on the position of the two objects, the shapes are ultimately two T intersections, he said.

By dropping objects and listening to the thunks and bangs, he explained the origin of sounds that have become words. And, by walking across the room, he pointed out elements in music such as pitch, loudness and melody.

Changizi's latest book explores how speech, music and writing evolved. Credit: changizi.com

“If you have a dog, you know exactly where he is in the house and probably what he is doing, just by listening to his movements,” Changizi said. The same goes for kids banging drawers in the kitchen.

Changizi explores this idea and more of his research in his latest book, Harnessed: How Language and Music Mimicked Nature and Transformed Ape to Man (Benbella 2011).

He said he has drawn a lot of inspiration from art, adding that artists and those in the humanities are the true experimentalists that must shape the complicated structures to affect human minds.

It’s these experimentalists who really know “what minds like or don’t like,” he said, adding that he turns to their work to explore the “universal regularities” that are being discovered about the mind.

*This passage is adapted from Changizi’s book. To read an excerpt, click here.

Blue Crab Love Is Indeed Blind

By Guest Post

On September 9, 2011

In Animals, Behavior/Psychology, Biology, Visualization

Guest post from graduate student Kia Walcott

A reconstruction of what a female crab may see of a displaying male when her lenses are off.

Female blue crabs (Callinectes sapidus) are literally blind when they choose their mates, according to new research from Duke biologists Jamie Baldwin and Sönke Johnsen.

Blue crabs are one of many crustacean species that undergo molting and mating at the same time. Because the multi-faceted lenses that make up the crab’s eyes are part of the exoskeleton, they too are shed. So it’s like a molting female has taken out her contact lenses.

Baldwin and Johnsen put the crabs in an eye exam of sorts, with a rotating black-and-white striped drum. When the crab can see, she will move her eyes in the same direction as the rotating stripes. When she can’t see, she will not perform this behavior. By finding the width between the stripes that the female no longer moves her eyes, Baldwin and Johnsen were able to measure visual acuity.

They found that a female’s vision can be blurry from 3 days prior to molting until 3-6 days after molting.

This means that during the critical time of mating, when these female crabs should be experiencing all of the romantic courtship behaviors displayed by male blue crabs like claw waving, standing tall on the walking legs, and rhythmic waving of swim paddles, these single ladies can’t see a thing.

The males, on the other hand, can see perfectly, and in fact, use their color vision to choose females with red claws versus those with claws of other hues. Baldwin and Johnsen say all hope is not lost for female blue crabs however. They believe that chemical cues, what we would call smell, may help overcome her blurred vision.

Other studies have found that visual sexual cues are nearly non-existent or at least not documented in species that mate and molt simultaneously like this. These findings may explain why, at least for one species, looks aren’t everything.

CITATION: Baldwin and Johnsen. (2011) Effects of molting on the visual acuity of the blue crab, Callinctes sapidus. J Exp Biol. 214: 3055-61. <http://jeb.biologists.org/content/214/18/3055.long>