Category: Behavior/Psychology Page 19 of 27

By Duncan Dodson

When I go home and reminisce with family about road trips we took or embarrassing moments they facilitated, eventually we’ll disagree on “what actually happened.” We’re all so certain—our memories unfold vividly yet contrarily. It’s clear the past can be subjective, but why is this so?

As part of Duke University’s Brain Awareness Week, I went to a talk at Fullsteam Brewery on imagining alternate realities by Dr. Felipe De Brigard, Assistant Professor of Philosophy and member of Center for Cognitive Neuroscience. De Brigard began by discussing studies of patients with hippocampal atrophy (as in amnesia, PTSD, and severe depression) struggling to place themselves in both the future and the past. Their impoverished answers contrast with those of healthy controls, suggesting a link between areas of the brain accessed for recalling the past and picturing the future.

Dr. Felipe De Brigard presents his recent studies on the relationship between the neural default network and autobiographical thoughts at Fullsteam Brewery 3/19.

De Brigard buttressed this by displaying fMRI neural images of parts of the brain used when imagining future events and evoking memories. These parts encompass the default network: a system of functions and firings executed when the brain is not engaged in a specific task. Evidence shows the default network allows engagement in “mental time travel” or the projection of oneself into the future or onto the singular, objective past. This assumption leads to temporal asymmetry: only one past exists with which the imagination can corroborate yet it can visualize limitless possibilities.

De Brigard challenged this view: what if the default network works in both directions? He argues that the parts of the brain used for imagining possible futures also allow us to conceive potential outcomes in our past that did not occur, the process of counterfactual thinking. He has found that when contemplating an alternative reality considered likely to have occurred, the brain behaves as if it were remembering. Memory is not haphazard reproduction but probabilistic reconstruction — our memory is constantly rebuilding the past with both fact and what are likely facts, and frequently the distinction is blurred.

A fascinated and packed Fullsteam; many audience members were at their second or third event for Brain Awareness week at Duke.

“Perhaps we should cut Brian Williams a little slack?” De Brigard chuckled. Ample evidence shows that engagement in especially rich and detailed counterfactual thinking can increase the probability of constructing — and believing the authenticity of — false memories.

More intriguing than pardoning Williams are potential contributions to treatment of anxiety, depression, and PTSD. A common debilitating trigger among these disorders is repetitive counterfactual thinking, “I shouldn’t have said that, I shouldn’t have said that.” Perhaps with further study on the default network and its relationship to autobiographical contemplations, neuroscientists might develop tools to alter the pathways or functionality of the default network.

As for my family, they have some major counterfactual thinking patterns to alter; my memory is immaculate.

Grave Effects of the Great Migration

By Robin Smith

On February 16, 2015

In Behavior/Psychology, Medicine

Sometimes a great move can have grave consequences — particularly when that move is a massive migration. In the 20th Century, millions of African-Americans relocated from the Deep South to search for greater quality of life in an exodus known as the Great Migration. However, the gains many made were clouded by higher mortality rates in old age. Despite having access to greater opportunities for work and education, Duke economist Seth Sanders found that men and women who relocated to the North and West were more likely to die before reaching their 70s than their counterparts who remained in the rural South. Here’s a glimpse at how city living took a late-life toll on migrants:

You can read the full story on Duke Today.

The Power of the Past

By Karl Bates

On January 30, 2015

In Behavior/Psychology, Field Research, Guest Post

Guest Post by Eric Ferreri, Duke News & Communications

If you grow up in the working class, neither love nor money can trump your blue-collar roots, a Duke sociologist has found.

Her study of couples from different social classes suggests that those who “marry up” still make life decisions based on their upbringing.

Sociologist Jessi Streib’s book “The Past” is about class structure in marriages.

“Your social class never goes away,” says Jessi Streib, an assistant professor of sociology whose findings are revealed in her new book: The Power of the Past: Understanding Cross-Class Marriages. “It stays with you in terms of how you live your life. The class you’re born into sticks with you and shapes you, even when you marry into more money and a far more financially secure life.”

Streib’s findings derive from interviews she conducted with white, heterosexual Midwestern couples. She interviewed 32 couples in which one spouse came from a working class background, the other from the middle class. For comparison, she also interviewed 10 couples in which both spouses grew up in the middle class.

Streib defines working class as people raised by parents with high school educations; the middle class subjects were raised by college-educated parents.

Her findings run contrary to the notion held by many scholars that strivers can outrun a difficult childhood by getting a college degree and good-paying middle-class job.

While the findings suggest that a middle class upbringing isn’t required to excel in the American workplace, those upwardly mobile people from working class roots may still miss out on opportunities if they can’t or don’t subscribe to the unspoken norms of middle class culture, Streib notes.

Streib found that couples from different classes held onto their own, firmly-rooted beliefs regarding money and parenting, often negotiating fervently with each other over the proper amount of career planning and nurturing of children. Should children be left to grow and discover on their own, or should goals and schedules be set for them?

“Those are the sorts of tiny battles cross-class couples have all the time,” Streib said. “These are not insurmountable obstacles, but they are certainly common and consistent.”

Death with Dignity: the Brittany Maynard Story

By sa160@duke.edu

On December 19, 2014

In Behavior/Psychology, Global Health, Medicine

By Nonie Arora

Is it acceptable for patients to choose to die on their own terms? Can physicians assist them with their wishes? Where do we draw the line for euthanasia and end-of-life decision making? Faculty and students discussed these thorny issues at a recent Science & Society Round Table event, co-hosted by the Duke Undergraduate Bioethics Society.

Brittany Maynard, “Death with Dignity” advocate. Credit: Wikipedia

This event was sparked by the recent events regarding Brittany Maynard. On November 1st, Maynard, a 29-year-old terminally ill cancer patient, chose to take a pill that ended her life.

During the roundtable, professor Dr. Jennifer Hawkins and paramedic Anita Swiman discussed this case as a launching point to delve into ethical issues regarding decision-making and “Death with Dignity” laws. Dr. Hawkins is a philosopher in bioethics and has studies quality of life issues and the nature of suffering. Swiman, an emergency medical technician, has insight into what it’s really like to deal with families who are making decisions about end-of-life care.

Because of her brain tumor, Maynard would have to undergo a very difficult process of death. She chose to relocate from California to Oregon to take advantage of their “Death with Dignity” statute. Previously, about 750 people – mostly elderly – had used the statute, but Maynard changed the discussion by being a young, vibrant woman talking about a decision to end her life, according to round table moderator, Michael “Buz” Waitzkin.

Dr. Hawkins described three main worries that come along with physician-assisted suicide. She said the first struggle is whether it can be in someone’s best interests to die. “Death is the enemy for most of us most of the time because we are healthy and have things we want to do,” she said. However, some people are suffering deeply. She questioned how can we distinguish between those that could be helped in what remains of their lives from those who cannot.

“Even if we can agree that sometimes it’s in a person’s best interests to die,” Dr. Hawkins explained, “We can disagree about the roles of physicians or other health care workers in this process.” Physicians generally operate by the code of doing no harm. Some people believe including physician-assisted suicide violates sacred codes of physician conduct.

Editorial Cartoon by Dan Wasserman of the Boston Globe

Finally, Hawkins said that even if we can agree that sometimes it is in some people’s best interests to die, and we don’t have a problems with physicians helping them, we may still worry about the effects on society of such a policy that permits physician-assisted suicide. She said that some people are concerned about how such a policy could impact end-of-life decision making if elders feel pressured to choose this option, against their own wishes, to not feel like a burden on their families.

“Will we be able to keep the policy restricted to the terminally ill, those who request it, and those who are able to take the prescription on their own?” Dr. Hawkins asked the group. She questioned why we restrict the application of “Death with Dignity” laws to those who can ask for a prescription. Some people who are paralyzed or cannot take prescriptions for themselves are excluded.

Paramedic Anita Swiman provided a perspective based on practice. “As a health care provider in prehospital medicine, there are clear laws that we must follow. If a patient meets certain criteria, we know what we will do. We take our personal feelings out of the discussion. We (sometimes face) assault from family members who want something different from what their family member had written in their wishes.”

Swiman said that pre-hospital providers act as counselors as well. She described that while being receptive to what family members are saying, paramedics sometime have to explain, “This is what the person wanted. This is what the law states. I would like to fix the situation for you, but there is nothing that I will be able to do for you.”

Ultimately, scholarly work that addresses the nature of suffering or examines consequences of “Death with Dignity” laws in different states could further inform the difficult ethical issue of physician-assisted suicide.

RISK: The Adolescent Mind

By Anika Radiya-Dixit

On November 25, 2014

In Behavior/Psychology, Neuroscience, Science Communication & Education

By Anika Radiya-Dixit

Have you ever been labeled an out-of-control teenager? A risky driver? An impulsive troublemaker? Here’s the bad news: That’s partially correct. The good news? It’s not your fault: blame the brain.

On November 18, the department of Psychology and Neuroscience introduced students to “The Origins of Heightened Risk Behavior in Adolescence.” The presenter, Dustin Albert, is a PhD research scientist at the Center for Child and Family Policy here at Duke University, who is interested in cognitive neuroscience, problem behaviors, and peer influence.

Researchers have identified the stage of adolescence as the peak time of health and performance, but at the same time, they noticed a jump in morbidity and mortality as children approached teen years, as seen in the graphs below. Specifically, adolescents show increased rates of risky behavior, alcohol use, homicide, suicide, and sexually transmitted diseases. However, as Allen tells the audience, “These are only the consequences.” In other words, what teenagers are stereotypically ridiculed for is actually the result of something else. If that’s the case, then what are the causes?

Professor Albert explaining the spike in risky behavior during teenage years.

Psychologically speaking, researchers believed that these behaviors are caused by a lack of rational decision, perhaps because adolescents “are unable to see their own vulnerability” to the outcomes, meaning that teens are apparently inept at identifying consequences to their actions. However, the studies they took demonstrated that adolescents are not only able to see their own vulnerability, but are also able to intelligently evaluate costs and effects to a certain decision. If teenagers are so smart, then what is actually causing this “risky behavior”?

One important reason Professor Albert discussed is brain activity and maturation before, during, and after adolescence. As a child ages from early to middle adolescence, fast maturation of incentive processing circuitry drives sensation seeking – in other words, the willingness to take risks in order to gain a reward increases as the child approaches teen years. In the brain, this occurs due to increased dopamine availability in reward paths as well as heightened sensitivity to monetary and social reward cues. In one interesting study, adolescents were instructed to press a button only when they saw an angry face. However, the researchers noticed that when the teens saw a happy face, they had a “particularly difficult time restraining themselves” to not press the button. Essentially, the happy-angry face study demonstrates that adolescents have more struggle in restraining themselves against impulsive actions, which often translates into responses during driving, alcohol use, and the other aforementioned risky behaviors.

Later in their life, there is a slower maturation of cognitive control circuitry that leaves a window of imbalance in the teen’s life. In the brain, this period is noted by thinning of gray matter and increasingly efficient cortical activation during inhibition tasks. In other words, older people “use smaller parts of [their] cortex to stop inappropriate responses.” Essentially, due to the way the physical and hormonal brain matures, adolescents are more prone to impulsive behavior. The take away: it’s not your fault.

Another influence on teens’ risky behavior is called the peer presence effect, commonly known as “peer pressure.” Based on arrest records, “adolescents, but not adults, [are] riskier in the presence of peers,” pointing out that the percentage of co-offenders arrested for the top eight crimes decreased with age after teenage years (Gardner & Steinberg, 2005). Perhaps the need to “establish their status,” Albert speculated, decreases with age as they gain more experience about living in the real world.

The test to evaluate the result of peer presence simulates the effect of teens taking a driving exam when in the car alone as compared to when with peers. In terms of peer influence, the study shows that adolescents ran more intersections when sitting with a peer than when sitting alone. In terms of risky behavior compared with adults, adolescents when watched by peers showed over 20% increase in risky behavior of running through intersections, as opposed to the 5-10% increase seen for adults in peer presence. Albert partially attributed this effect to the fact that “teens driving the first time could assess the probability of crashing less than adults do,” but he doesn’t have specific evidence for this claim.

While Albert claimed that the study was valid because the adolescents participating were made aware of the outcome of driving recklessly – damage to the car, injury, time it would take to get a new car, insurance problems – I believe that the study should have taken into account the fact that the teens may have subconsciously known the simulated driving test wasn’t real – viewing it as a mere video game – and so may have succumbed more into peer pressure as the true fear of dying in a crash would not have been present.

Albert ended his talk by giving one last piece of advice to people working with teens: It’s “not enough to [simply] increase their knowledge,” but rather to “understand and work towards developing impulse control and reward sensitivity.”

Below are some of the thought-provoking questions raised by audience members during the Q&A session:

Q: What would be the result of peer presence effect for same-sex peers as compared to peers of the opposite sex?

A: While Albert admitted that this particular situation has not been tested yet, he believes it may be based on personal perceptions of what the peer thinks, and what the opposite person likes.

Q: What would be the result of risky behavior for the simulated driving test if the participant’s parent(s) and peer(s) were both present in the car?

A: On one hand, the participant might drive more carefully due to the presence of an authoritative figure. However, if the participant opinionates the peer as a stronger influence, he / she would effectively neutralize the effect the parent has and drive more recklessly. Other audience members claimed that they would drive more cautiously irrespective of who was sitting with them in the car because they are aware there is another life at stake for every decision they made behind the wheel. “It would be interesting to see the [results of the study] based on this internal conflict,” the audience member who posed this question said. Overall, Albert said the results would be primarily influenced by the type of person participating – whether they would “take the small amount of money or be willing to wait for the big amount” in front of peers – that would determine whether the parent or peer becomes a stronger influence in risky behavior.

Q: How could someone going into education help keep high school students away from risky behaviors?

A: Albert noted that these behaviors are more the result of personal experience rather than something that can be quickly taught. In a school setting, teachers could introduce the practice of challenging situations to help the kids acting ‘in-the-moment’ recognize and understand “changes in their own thought patterns for decision making,” but simply giving them a “lesson in health class is not necessarily going to translate into the Friday night situation.”

If you are interested in these type of topics, Professor Albert is teaching PUBPOL 241: METHODS SOCIAL POLICY RESEARCH this Spring (2015).

More details about the presenter can be read at: http://fds.duke.edu/db/Sanford/ccfp/william.albert

Why Airport Scanners Catch the Water Bottle but Miss the Dynamite

By Robin Smith

On November 24, 2014

In Behavior/Psychology, Computers/Technology, Guest Post, Neuroscience

Guest post by Caroline Drucker

A screenshot of the Airport Scanner game, with a suitcase containing two dynamite sticks. Courtesy of the Mitroff Lab and the Kedlin Company.

You’re at the airport waiting to pass through security and board your flight. The security agent stops the person in line ahead of you: there was a full water bottle in his carry-on bag. He throws out the bottle and proceeds through the airport. Later that evening, you see that person’s face on the news, for having pulled out dynamite on their flight. Why did the TSA agent overlook the dynamite?

A team of researchers at Duke led by Dr. Stephen Mitroff is using a cell phone game to provide answers to this and other questions about airport baggage screenings. Last year, they reported that luggage screeners are likely to miss extremely rare illegal items. In a new study which will appear in the Journal of Experimental Psychology: Human Perception and Performance, Dr. Mitroff’s team once again leverages the power of big data to address a different issue: what happens when a carry-on suitcase contains multiple illicit items?

Baggage screening is an example of what cognitive scientists refer to as visual search: attempting to locate a target among a crowded visual display. Many laboratory studies have demonstrated that when more than one target is present in the display, people are less likely to find additional targets once they have spotted a first target. One possible reason for this “subsequent search misses” phenomenon is that people become biased toward searching for targets that match the first target. That is, a baggage screener who finds a water bottle might enter “water bottle” mode and be unprepared to see dynamite. This theory is most likely to hold in situations with large and unpredictable sets of targets – which is precisely why it has been difficult to test in the lab, where the relatively small amount of trials that subjects can perform has limited the possible target numbers and frequencies.

A smartphone game called Airport Scanner circumvents this problem. In the game, players act as TSA agents and view X-ray images of carry-on luggage, earning points for correctly tapping illegal items. More than 200 possible illegal items can appear, and each bag can contain between zero and three illegal items among up to twenty legal items. The game is available as a free download from the Kedlin Company, who share the data with the Mitroff lab. They have now collected close to two billion trials (bags searched) from over seven million people, which would take centuries to collect in the lab.

Using these data, Dr. Mitroff and his colleagues were able to make an important discovery about subsequent search misses. When two identical targets are present in a bag, it is more likely that both will be found than when two different targets are present. In other words, if someone first spots a water bottle, it is more likely that they will also find a second item if it is a water bottle than if it is dynamite.

This result supports the theory that finding a visual target biases a person’s perceptions. We become better prepared to find another instance of the same item, rather than a different item. According to Dr. Mitroff, “Knowing this fact can help create search environments and standard operating procedures to overcome this priming effect.”

NIH Getting Serious about the BRAIN

By Karl Bates

On October 9, 2014

In Behavior/Psychology, Biomedical Engineering, Neuroscience

The NIH’s mapping initiative called BRAIN has been likened to a moon shot.

By Kelly Rae Chi

The federal government’s BRAIN Initiative to chart the neural connections in the human brain and explain how its diverse and ever-changing cells make us who we are has been compared to landing a person on the moon.

Last summer the National Institutes of Health (NIH) described its vision as a 100-plus-item list of deliverables, proposed budgets and milestones. Last week, the NIH awarded the first round of seed money toward those goals — $46 million — some it for Duke scientists.

And this week, Gregory Farber, director of the National Institute of Mental Health’s Office of Technology Development and Coordination, visited Duke to talk about the timeline for the decade-long initiative.

Duke scientists in the audience peppered him with questions about how he sees it evolving.

“What I learned in Greg Farber’s talk is that the BRAIN Initiative offers a serious –and I mean serious — ten-year plan to catalyze game-changing discoveries in understanding the human brain, and in doing so, provide new treatments for disorders, like Alzheimer’s disease, that can rob us of our very humanity,” said Michael Platt, director of the Duke Institute for Brain Sciences.

BRAIN stands for ‘Brain Research through Advancing Innovative Neurotechnologies.’ It’s all about technology, and it will cost a pretty penny for its public and private partners. Fiscal Year 2014’s $46 will develop a “parts list” for the brain and probe neural circuitry in a variety of ways. And that’s only the start.

The initiative is expected to begin in earnest in 2016, take five years for tool development and five more to apply those tools to study humans wherever possible.

“We have a strong sense that we want to see these tools have clinical applications in the not-too-distant future, but I’m being careful not to define ‘not-too-distant’,” Farber told a room full of neuroscientists, many of them working on human brain imaging.

Allen Song is a professor of Radiology, Neurobiology, Psychiatry and Biomedical Engineering.

In the audience was Allen Song, professor and director of the Duke-UNC Brain Imaging Analysis Center and among the first scientists awarded NIH BRAIN funds. He is leading a team that will further develop and validate a human brain imaging technique dubbed ‘NEMO,’ for Neuro-Electro-Magnetic Oscillations.

The hope is that NEMO, and other ‘next-generation’ brain imaging advances supported with the initiative, will help solve some of the limitations of today’s technologies. Functional magnetic resonance imaging (fMRI), for example, measures changes in the levels of oxygenated blood in the brain. It’s an indirect way of seeing neural activity, and it comes with a several-second delay.

Used with traditional MRI scanners, NEMO will more directly tune into neurons, which naturally create waves of electrical activity in the brain at specific frequencies.

For example, “if this technology works, we can tune our machine to listen to the 10-Hertz oscillation in the brain as a result of neuron firing,” Song said. Then, by driving neurons into specific oscillations at different times and during different tasks, the scientists may be able to resolve the brain in better spatial and temporal detail.

Song said that although he’s excited and confident, he already feels the pressure of a tight timeline for the project. It won’t be possible to finish it in the three-year timeframe. Even with continued funding, at the end of 12 years, “we don’t know where we will be,” he said.

Still, Song and his colleagues were all smiles as they filed in for Farber’s talk. “It’s a thrill to see Allen Song and his colleagues win support in the first round of BRAIN grants to develop the next generation in human brain imaging technology,” Platt said. “I’m confident Duke neuroscience will figure prominently in the BRAIN Initiative, given our focus on interdisciplinary innovation and collaboration.”

No actual cartoon fish will be used in the NEMO project.

Artistic Anatomy: An Exploration of the Spine

By Olivia Zhu

On October 8, 2014

In Behavior/Psychology, Biomedical Engineering, Medicine, Science Communication & Education, Visualization

By Olivia Zhu

How many times have you acted out the shape of a vertebra with your body? How many times have you even imagined what each of your vertebrae looks like?

On Wednesday, October 1, Kate Trammell and Sharon Babcock held a workshop on the spine as part of the series, Namely Muscles. In the interactive session, they pushed their audience members to gain a greater awareness of their spines.

Participants assemble vertebrae and discs of the spine

Trammell and Babcock aim to revolutionize the teaching of anatomy by combining art, mainly through dance, and science. They imagine that a more active, participatory learning style will allow students from all backgrounds to learn and retain anatomy information much better. Babcock, who received her Ph.D. in anatomy from Duke, emphasized how her collaboration with Trammell, a dancer and choreographer, allowed her to truly internalize her study of anatomy. The workshop participants, who included dancers and scientists alike, also reflected a fusion of art and science.

Trammell observes the living sculptures of thoracic vertebrae

To begin the exploration of the spine, Trammell and Babcock had participants close their eyes and feel models of individual vertebrae to gain tactile perception. Trammell and Babcock then instructed participants to make the shape of the vertebrae they felt with their bodies, creating a living sculpture garden of various interpretations of vertebrae–they pointed out key aspects of vertebrae as they walked through the sculptures.

Finally, Trammell and Babcock taught movement: in small groups, people played the roles of muscles, vertebrae, and spinal discs. They worked on interacting with accurate movements (for example, muscles only pull; they cannot push) to illustrate different movements of the spine.

Interactive illustration of a muscle pulling vertebrae

To complete the series, Trammell performed Namely, Muscles, choreographed by Claire Porter, on October 4^th at the Ark.

Duke Shaking up Basal Ganglia Research

By Karl Bates

On October 8, 2014

In Behavior/Psychology, Neuroscience

By Kelly Rae Chi

Duke brain scientists are shaking up their field’s understanding of a part of the brain called the basal ganglia that’s sort of a crossroads for many important functions.

A simplified map of the pathways domamine and serotonin travel to the basal ganglia, the snail-shaped structure in the middle of the human brain.

A simplified map of the pathways dopamine (blue) and serotonin travel to the basal ganglia, the snail-shaped structure in the middle of the human brain.

Basal ganglia signaling is involved in movement, learning, language, attention, and motivation. But this centrality also makes it challenging to figure out how it works, said Henry Yin, an assistant professor of psychology and neuroscience at Duke, and a member of the Duke Institute for Brain Sciences.

As healthy mice collected food pellets delivered into a cup once per minute every minute for two hours. Yin’s team was recording the electrical activity of neurons projecting to and from the basal ganglia.

Henry Yin is an assistant professor in Psychology and Neuroscience.

Naturally, the mice picked up food less often as they became full and some of the cells that use dopamine to signal reward showed less activity.

But other dopamine cells became more active.

In a paper describing these experiments , Yin’s group proposed that the cells’ activity reflected not reward but what the animals are physically doing.

This was new and Yin became curious. Was there a direct relationship between movement and dopamine activity?

Using a different experimental setup with cameras and pressure pads, Yin’s group quantified mouse movements while recording neural activity. “What happens is that whenever there’s movement, (there are phases of) dopamine activity,” Yin said to a room full of fellow neuroscientists during a recent seminar at Duke.

Putting the mice on top of a “shaker,” a piece of lab equipment normally used to gently shake tubes and dishes full of liquids, they found individual dopamine neurons responded to specific directions the mouse was tilted on the shaker. The same was true for nearby neurons that signal using GABA, an inhibitory chemical in the brain.

Using additional methods for tracking motions of freely moving mice, the group has discovered specific sub-populations of neurons that respond to different aspects of movement, especially movement speed and acceleration.

The researchers have also created transgenic mice whose dopamine neurons can be stimulated using light. Turning on these neurons makes the mice move.

Yin is working on publishing these results, but he said there’s a lot of resistance in the field. His work appears to be directly challenging the dogma that dopamine is linked to reward. He says it might actually be involved in generating movements.

“Let’s say you’re drinking coffee and that’s a reward,” Yin said. “I record your neural activity, and it’s correlated with coffee. You might say it’s a coffee neuron. But that’s not true unless you can measure the movement kinematics and rule out other possible correlations. What we’re seeing is that, with no exceptions, the phasic activity of DA neurons is always correlated with movement.”

Yin’s work also challenges theories about why people with Parkinson’s disease, whose dopamine cells degenerate, often have trouble initiating movement, or they move more slowly than they mean to.

“If you’re a doctor, a neurologist, what you study is the rate model. That’s the textbook description,” Yin said. The gist of the rate model is that the basal ganglia is constantly putting the “brakes” on behavior, and when its neurons settle down, that allows for movement. Parkinson’s patients can’t initiate movements, it’s thought, because their basal ganglia output (more specifically, the rate of firing in the inhibitory output neurons) is too high, producing excessive braking.

In contrast, according to Yin’s work, at least four different types of basal ganglia output neurons are adjusting behavior dynamically and continuously, to shape the speed and direction of movement.

When the activity of these neurons is constant, it reflects a stable posture, Yin said. So he argues that the problem with Parkinson’s patients is not that their basal ganglia output is too high, but that this output is stuck in firing mode. The downstream brain areas required for postural control don’t get the right commands.

Nicole Calakos is an associate professor of neurology.

“Henry’s studies are really exciting because we’ve thought about this circuitry in one way for a very long time and his findings really cast a new light on those interpretations,” said Nicole Calakos, M.D., Ph.D., an associate professor of neurology. “I treat patients with Parkinson’s disease and other diseases that involve this circuitry. It is interesting to consider this alternate view to explain the problems my patients face in doing their day-to-day activities.”

Calakos’ own research focuses on how learning alters signal processing by the basal ganglia, and how the signaling goes awry in brain diseases such as obsessive-compulsive disorder. Duke researchers are finding compelling links between different behavioral states and specific long-lasting patterns of activity in the basal ganglia.

Duke Neuroscientist Teaching about This Week's Nobel

By Karl Bates

On October 7, 2014

In Behavior/Psychology, Faculty

By Kelly Rae Chi

Talk about great timing!

Jennifer Groh, a professor of psychology and neuroscience at Duke, is launching a Coursera course next week and a book next month — both devoted to the topic of the 2014 Nobel Prize in Physiology or Medicine which was awarded Monday.

This year’s Nobel went to three scientists who discovered the neurons responsible for our brain’s form of GPS, crucial for our ability to navigate a complex and changing world. And that’s the topic of Groh’s work, “Making Space: How the Brain Knows Where Things Are.”

The cover of Jennifer Groh’s new book.

In 1971, John O´Keefe of University College London had shown that certain neurons in the hippocampus — a brain area known for its role in memory — are active only when a rat is in certain spot in its environment. O’Keefe called these neurons ‘place cells.’

In 2005, May-Britt Moser and Edvard Moser, partners in both marriage and science at the Norwegian University of Science & Technology in Trondheim, described a region near the hippocampus in which cells became activated in a unique grid-like pattern as an animal moved through its environment. They dubbed them ‘grid cells.’

“O’Keefe and the Mosers made a discovery that I find endlessly fascinating — that a brain network closely tied with memory is extremely sensitive to one’s location in space,” Duke’s Groh said. “This suggests that our movements through the world play a role in helping us remember.”

Jennifer Groh is a professor of Psychology and Neuroscience.

“Once you know this, you see the implications everywhere,” said Groh who is also a member of the Duke Institute for Brain Sciences. “For example, when you go to a college reunion and are roaming your old haunts, long dormant memories come flooding back.”

Groh’s new book, Making Space: How the Brain Knows Where Things Are, explains more about how our brains convey a sense of location and direction. In it, Groh makes the case that such spatial processing is inextricably tied to our ability to think and remember.

Her openly available Coursera course based on the book, “The Brain and Space,” starts Monday, October 13. To celebrate the Mosers and O’Keefe winning the prize, she made her lecture on the place cells available on YouTube.

[youtube http://www.youtube.com/watch?v=ocm81AkkXSw?rel=0]

Following the people and events that make up the research community at Duke

Category: Behavior/Psychology Page 19 of 27

Imagining Alternate Realities: Is Brian Williams in the Clear?

Grave Effects of the Great Migration

The Power of the Past

Death with Dignity: the Brittany Maynard Story

RISK: The Adolescent Mind

Why Airport Scanners Catch the Water Bottle but Miss the Dynamite

NIH Getting Serious about the BRAIN

Artistic Anatomy: An Exploration of the Spine

Duke Shaking up Basal Ganglia Research

Duke Neuroscientist Teaching about This Week's Nobel