Duke Research Blog

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

Category: Behavior/Psychology Page 1 of 20

Vaping: Crisis or Lost Opportunity?

Wikimedia Commons

Whether you’re doing vape tricks for YouTube views or kicking yourself for not realizing that “USB” was actually your teenager’s Juul, you know vaping is all the rage right now. You probably also know that President Trump has called on the FDA to ban all flavored e-cigarettes to combat youth vaping. This comes in reaction to the mysterious lung illness that has affected 1,080 people to date. 18 of them have died.

At Duke Law School’s “Vaping: Crisis or Lost Opportunity” panel last Wednesday, three experts shared their views. 

Jed Rose, a professor of psychiatry and behavioral sciences and director of the Duke Center for Smoking Cessation, has worked in tobacco research since 1979, focusing on smoking cessation and helping pioneer the nicotine patch. Rose also directs Duke’s Center for Smoking Cessation.

According to Rose, e-cigarettes are more effective than traditional Nicotine Replacement Therapy (NRT). A recent study found that e-cigarettes were approximately twice as effective as the state-of-the-art NRT in getting smokers to quit combustible cigarettes (CCs). This makes sense because smokers are addicted to the action of puffing, so a smoking cessation tool that involves inhaling will be more successful than one that does not, like the patch.

Rose also took issue with the labeling of the current situation surrounding vaping as an “epidemic.” He called it a “crisis of exaggeration,” then contrasted the 18 deaths from vaping to the 450 annual deaths from Tylenol poisoning

Even in the “pessimistic scenario,” where e-cigarettes turn out to be far more harmful than expected, Rose said deaths are still averted by replacing cigarettes with e-cigarettes. 

The enemy, Rose argued, is “disease and death, not corporations”, like the infamous (and under-fire) Juul. 

James Davis, MD, an internal medicine physician and medical director for the Center for Smoking Cessation, works directly with patients who suffer from addiction. His research focuses on developing new drug treatments for smoking cessation. Davis also spearheads the Duke Smoke-Free Policy Initiative.

Davis began by calling for humility when using statistics regarding e-cigarette health impacts, as long-term data is obviously not yet available. 

Davis did present some known drawbacks of e-cigarettes, though, stating that e-cigarettes are similarly addictive compared to conventional cigarettes, and that a whopping 21% of high school students and 5% of middle school students use e-cigarettes. Davis also contended that “When you quit CCs with e-cigarettes, you are merely transferring your addiction to e-cigarettes. Eighty-two percent [of test subjects who used e-cigarettes for smoking cessation] were still using after a year.” 

However, according to Davis, there is a flipside. 

Similar to Rose, Davis looked to the “potential for harm reduction” — e-cigarettes’ morbidity is projected to be only 5-10% that of CCs. If the main priority is to get smokers off CC, Davis argues e-cigarettes are important: 30-35% of CC smokers say they would use an e-cigarette to quit smoking, where only 13% would use a nicotine patch. 

Furthermore, Davis questioned whether the mysterious lung disease is attributable to e-cigarettes themselves — a recent study found that 80% of a sample of afflicted subjects had used (often black-market) THC products as well.

Lauren Pacek, an assistant professor in psychiatry and behavioral sciences at Duke, examines smoking in the context of addiction and decision-making.

Pacek stated that flavored electronic nicotine delivery systems (ENDS) are important to youth: 61-95% of current youth ENDS users use flavored products, and 84% of young users say they would not use the products without flavors. So, banning flavored ENDS would ostensibly reduce young adults’ use, potentially keeping them off nicotine entirely.

However, Pacek pointed to the importance of flavors for adult users too: the ones that are purportedly using ENDS not for recreation or social status (as young people have been known to do), but for smoking cessation. Many former CC smokers report that flavored ENDS were important for their cessation. By banning flavored ENDS, the products look less appealing, and smokers are more likely to return to much more harmful cigarettes.  

So where do we go from here? 

Pacek did not take a concrete stance, but said her “take-home message” was that policymakers need to consider the impact of the ban on the non-target population, those earnest cigarette smokers looking to quit, or at least turn to a less harmful alternative. 

Rose also did not offer a way forward, but made clear that he does not support the FDA’s impending ban on flavored e-cigarettes and thinks the hysteria around vaping is mostly unfounded.

Davis did not suggest a course of action for the US, but as leader of Duke’s Smoke-Free Policy Initiative, he certainly suggested a course of action for Duke. The Initiative prohibits combustible forms of tobacco at Duke, but does not (yet) prohibit e-cigarettes. 

By Zella Hanson

Across the Atlantic: Caribbean Music and Diaspora in the UK

According to Professor Deonte Harris, many of us here in the U.S. have a fascination with Black music. But at the same time, we tend not to realize that it’s. . . well, Black music.

Harris, an International Comparative Studies professor at Duke, holds a freshly minted Ph.D. in Ethnomusicology from UCLA. At the moment, his research focuses especially on the practice and influence of Afro-Caribbean music and diaspora in London.

Image result for deonte harris ethnomusicology
Deonte Harris, Ph.D.,
Assistant Professor of the Practice of the International Comparative Studies Program

He chose to conduct his research in the UK because of its large overseas Caribbean population and because he found that not much scholarship was dedicated to Black Europe. “It’s such a rich space to think about different historical entanglements that affect the lives and trajectories of Black people,” he explained.

Those entanglements include the legacies of colonialism, the Slave Trade, empire, and much more. The racialization of such historical processes is necessary to note.

For example, Harris found that a major shift in Black British music occurred in the 1950s due to anti-Black racism in England. Black individuals were not allowed to socialize in white spaces, so they formed community in their own way: through soundsystems.

These soundsystem originated in Jamaica and debuted in the UK in the postwar years. A soundsystem was the organization of Black individuals, music, and machines, typically in basements and warehouses, for the enjoyment of Black music and company. It became a medium through which a Black community could form in a racialized nation.

Notting Hill Carnival 2007 004.jpg
Notting Hill Carnival, London: An annual celebration of Black British culture.
Photo by Dominic Alves.

Today, Black British music has greatly expanded, but still remains rooted in sound systems.

While the formation of community has been positive, Harris explains that much of his research is a highly complex and often disheartening commentary on Blackness.

Blackness has been created as a category by dominant society: the white community, mostly colonizers. Black music became a thing only because of the push to otherize Black Britons; in many ways, Black culture exists only as an “other” in relation to whiteness. This raises a question of identity that Harris continues to examine: Who has the power to represent self?

In the U.S. especially, Black music is a crucial foundation to American popular music. But as in the UK, it finds its origins in community, folk traditions, and struggle. The industrial nature of the U.S. allows that struggle to be commercialized and disseminated across the globe, creating a sort of paradox. According to Harris, Black individuals must reconcile “being recognized and loved globally, but understanding that people still despise who you are.”

To conduct his research, Harris mostly engages in fieldwork. He spends a significant amount of time in London, engaging with Black communities and listening to live music. His analysis typically involves both sonic and situational elements.

But the most valuable part of Harris’ fieldwork, perhaps, is the community that he himself finds. “Ethnomusicology has for me been a very transformative experience,” he said. “It has helped me to create new global relationships with people ⁠— I consider myself now to have homes in several different places.”

By Irene Park

Researchers Urge a Broader Look at Alzheimer’s Causes

Just about every day, there’s a new headline about this or that factor possibly contributing to Alzheimer’s Disease. Is it genetics, lifestyle, diet, chemical exposures, something else?

The sophisticated answer is that it’s probably ALL of those things working together in a very complicated formula, says Alexander Kulminski, an associate research professor in the Social Science Research Institute. And it’s time to study it that way, he and his colleague, Caleb Finch at the Andrus Gerontology Center at the University of Southern California, argue in a recent paper that appears in the journal Alzheimer’s and Dementia, published by the Alzheimer’s Association.

Positron Emission Tomography scan of a brain affected by cognitive declines . (NIH)

“Life is not simple,” Kulminski says. “We need to combine different factors.”

“We propose the ‘AD Exposome’ to address major gaps in understanding environmental contributions to the genetic and non-genetic risk of AD and related dementias,” they write in their paper. “A systems approach is needed to understand the multiple brain-body interactions during neurodegenerative aging.”

The analysis would focus on three domains, Kulminski says: macro-level external factors like rural v. urban, pollutant exposures, socio-economcs; individual external factors like diet and infections; and internal factors like individual microbiomes, fat deposits, and hormones.

That’s a lot of data, often in disparate, broadly scattered studies. But Kulminski, who came to Duke as a physicist and mathematician, is confident modern statistics and computers could start to pull it together to make a more coherent picture. “Twenty years ago, we couldn’t share. Now the way forward is consortia,” Kulminski said.

The vision they outline in their paper would bring together longitudinal population data with genome-wide association studies, environment-wide association studies and anything else that would help the Alzheimer’s research community flesh out this picture. And then, ideally, the insights of such research would lead to ways to “prevent, rather than cure” the cognitive declines of the disease, Kulminsky says.  Which just happens to be the NIH’s goal for 2025.

Leaving the Louvre: Duke Team Shows How to Get out Fast

Students finish among top 1% in 100-hour math modeling contest against 11,000 teams worldwide

Imagine trying to move the 26,000 tourists who visit the Louvre each day through the maze of galleries and out of harm’s way. One Duke team spent 100 straight hours doing just that, and took home a prize.

If you’ve ever visited the Louvre in Paris, you may have been too focused on snapping a selfie in front of the Mona Lisa to think about the nearest exit.

But one Duke team knows how to get out fast when it matters most, thanks to a computer simulation they developed for the Interdisciplinary Contest in Modeling, an international contest in which thousands of student teams participate each year.

Their results, published in the Journal of Undergraduate Mathematics and Its Applications, placed them in the top 1% against more than 11,000 teams worldwide.

With a record 10.2 million visitors flooding through its doors last year, the Louvre is one of the most popular museums in the world. Just walking through a single wing in one of its five floors can mean schlepping the equivalent of four and a half football fields.

For the contest, Duke undergraduates Vinit Ranjan, Junmo Ryang and Albert Xue had four days to figure out how long it would take to clear out the whole building if the museum really had to evacuate — if the fire alarm went off, for instance, or a bomb threat or a terror attack sent people pouring out of the building.

It might sound like a grim premise. But with a rise in terrorist activity in Europe in recent years, facilities are trying to plan ahead to get people to safety.

The team used a computer program called NetLogo to create a small simulated Louvre populated by 26,000 visitors, the average number of people to wander through the maze of galleries each day. They split each floor of the Louvre into five sections, and assigned people to follow the shortest path to the nearest exit unless directed otherwise.

Computer simulation of a mob of tourists as they rush to the nearest exit in a section of the Louvre.

Their model uses simple flow rates — the number of people that can “flow” through an exit per second — and average walking speeds to calculate evacuation times. It also lets users see what happens to evacuation times if some evacuees are disabled, or can’t push through the throngs and start to panic.

If their predictions are right, the team says it should be possible to clear everyone out in just over 24 minutes.

Their results show that the exit at the Passage Richelieu is critical to evacuation — if that exit is blocked, the main exit through the Pyramid would start to gridlock and evacuating would take a whopping 15 minutes longer.

The students also identified several narrow corridors and sharp turns in the museum’s ground floor that could contribute to traffic jams. Their analyses suggest that widening some of these bottlenecks, or redirecting people around them, or adding another exit door where evacuees start to pile up, could reduce the time it takes to evacuate by 15%.

For the contest, each team of three had to choose a problem, build a model to solve it, and write a 20-page paper describing their approach, all in less than 100 hours.

“It’s a slog fest,” Ranjan said. “In the final 48 hours I think I slept a total of 90 minutes.”

Duke professor emeritus David Kraines, who advised the team, says the students were the first Duke team in over 10 years to be ranked “outstanding,” one of only 19 out of the more than 11,200 competing teams to do so this year. The team was also awarded the Euler Award, which comes with a $9000 scholarship to be split among the team members.

Robin Smith – University Communications

Innocent Until Proven Guilty? Well, That Depends

This is the last of eight blog posts written by undergraduates in PSY102: Introduction to Cognitive Psychology, Summer Term I 2019.

In the criminal justice system, one might imagine that the more serious a crime is, the more extensive the evidence should be to support the verdict. However, a recent study conducted at Duke University finds that jurors assessment of guilt is less reliant on the type of evidence and more on the severity of the crime.

Mock jurors in the study were more likely to find someone charged with murder guilty than someone charged with robbery.

A still from the movie “Twelve Angry Men” (1954), a tense drama about jury deliberations.

Numerous scholars have looked at how flawed forensic evidence, mistaken eyewitness identifications and defendants’ prior criminal convictions can introduce errors in criminal prosecutions.

But John Pearson, an assistant professor in four Duke departments including neurobiology, and his colleagues in law wanted to know whether the type of crime can also lead to a greater chance of wrongful conviction. It may be that jurors use moral and emotional responses to various crimes as reasoning for the decisions they make regarding the defendant’s guilt.

The researchers aimed to understand the relationship between crime severity and confidence in guilt by seeing how mock jurors, practicing prosecutors, and other practicing lawyers weigh various types of evidence in order to make a decision on guilt.

John Pearson

Participants in the study were subjected to about 30 crime scenarios, each one paired with a random variety of types of evidence. After participants read through each respective scenario, they rated the strength of the case on a 0-100 scale and their emotional and moral responses.

It appeared that the more threat or outrage they felt toward crime type, the more likely they were to find the defendant guilty.

The authors also tested different types of evidence’s potential interaction with people’s beliefs.

They found that both DNA and non-DNA physical evidence had the highest amount of influence on participants, but the difference between how the participants weighed them was small. The jurors appeared to place very similar, if not the same amount of weight onto these two types of evidence in terms of their confidence.

Pearson refers to juror’s equal weight of DNA and non DNA evidence as the “CSI effect.” But DNA evidence is far more reliable than non DNA evidence. The CSI effect lays out that jurors tend to give more weight to conclusions based on traditional evidence. The study found that no matter one’s position, the pattern of similar weight between the DNA and non DNA evidence was found across all groups. The study also states that “subjects tend to overweight widely used types of forensic evidence, but give much less weight than expected to a defendant’s criminal history.”

Along with finding similar patterns between confidence in guilt and evidence type, researchers also discovered an intense link between the subject’s confidence in guilt with the severity of the crime.

Notably for jurors, crime type highly influenced their perception of confidence in guilt. The study showed a positive correlation between personal, emotional, and moral biases and “adjudicative bias,’ or the likelihood of conviction.

And while jurors did show more of a trend in this finding, practicing lawyers and prosecutors also exhibited a crime-type bias correlation with the seriousness of crime, even though it was much smaller.

The study’s results model how punishment, outrage, and threat are almost entirely dependent on crime effect and crime scenario. This indicates that despite how much evidence was presented, crime type alone influenced jurors decisions to charge someone as guilty of that crime more frequently.

(Bang) Guilty!

This could mean that regardless of how much evidence or what type of evidence is present, innocent people wrongly charged of crimes could more easily be convicted if it is a more severe offense.

These findings indicate how easy it is to reach wrongful convictions of severe crimes within the US criminal justice system.

Guest post by Casey M. Chanler

6-Month-Old Brains Are Categorically Brilliant

This is the seventh of eight blog posts written by undergraduates in PSY102: Introduction to Cognitive Psychology, Summer Term I 2019.

Let’s say you visit your grandmother later today and come across a bowl of unknown exotic berries that look and taste similar to a raspberry. Your grandmother tells you that they are called bayberries. How would your mind react to the new word “bayberry”?

Research shows that an adult brain would probably categorize the word “bayberry” into the category of berries, and draw connections between “bayberry” and other related berry names.

But how do you think an infant would deal with a word like “bayberry”? Would he or she categorize the word the same way you would?

Elika Bergelson, a developmental psychologist at Duke University, provided some possible answers for this question in a study published in the Proceedings of National Academy of Sciences.

Six-month-old infants were shown two objects on a screen simultaneously, as a speaker provided labeling for one of the objects (eg. Look at the dog!).

The thing on the right is a shoe, sweetie. We’re not sure about that other thing…

The two objects were either literally related or unrelated. For example, the words nose and mouth are semantically, or literally, related since they both refer to body parts, while the words nose and boots are semantically unrelated.

As the babies were presented with these objects, their eye movements were tracked. The longer a baby stared at an object, the more confident he or she is presumed to be about the object’s match with the label. This acted as an indicator of how well the baby understood which object the label was referring to.

If the infants categorized words into semantically related groups, then they’d be more likely to confuse objects that are related. This means that the infants would perform better at choosing the correct object when the objects are unrelated.

The results suggest that infants approach words no differently than adults. The babies correctly identified the labeled object more frequently when the two were unrelated than when the two objects were related. This indicates that babies have the mental representation of words categorized into semantically related groups. When encountering two unrelated objects, babies can quickly distinguish between the two objects because they do not belong to the same mental category.

Elika Bergelson

However, when the two objects are related, the infants often confuse them with each other because they belong to the same or closely related categories — while 6-month-olds have developed a general categorization of nouns, their categories remain broad and unrefined, which causes the boundaries between objects in the same category to be unclear.

So what do all these results mean? Well, back to the bayberry example, it means that a 6-month-old will place the word “bayberry” into his or her mental category of “berries.” He or she might not be able to distinguish bayberries from raspberries the next time you mention the word “bayberry,” but he or she will definitely not point to bayberries when you drop the word “milk” or “car.”

Toddler Rock

If the results of this study can be replicated, it means that the infant approach to language is much more similar to adults than researchers previously thought; the infants have already developed a deep understanding of semantics that resembles grown-ups much earlier than researchers previously speculated.

While the results are exciting, there are limitations to the study. In addition to the small sample size, the infants mainly came from upper middle class families with highly educated parents. Parents in these families tend to spend more time with their infant and expose the infant with more words than parents with lower socio-economic status. So these findings might not be representative of the entire infant population. Nevertheless, the study sheds light on how infants approach and acquire words. It’s also possible this finding could become a new way to detect language delay in infants by the age of six-months.

Guest post by Jing Liu, a psychology and neuroscience major, Trinity 2022.

A Mind at Rest Still Has Feelings

This is the sixth of eight blog posts written by undergraduates in PSY102: Introduction to Cognitive Psychology, Summer Term I 2019.

Emotions drive our everyday lives: They help us make decisions, they guide us into acting certain ways and they can even define who we are as people. But when we take a break from our busy lives and rest, does our brain do the same?

A 2016 study by Duke researchers tested whether neural models developed to categorize distinct emotional categories in an MRI brain scan would work with people who are in a resting state, meaning no activity is being done by the person physically or mentally.

An algorithm determined different patterns of brain activity that mapped to different emotional states.

When a person is active, emotions are usually a huge part of the ways they interact and the decisions they make, but this study led by Kevin LaBar a professor of psychology and neuroscience, wanted to see if changing the activity level to its minimum can cause different effects on the person and the emotions they experience.

They used a tool called functional magnetic resonance imaging (fMRI) that allows scientists to measure brain activity by seeing the amount of blood flow to different areas in the brain. They were looking for universal emotions, those feelings that are understood in all cultures and societies as the same state of mind, such as contentment, amusement, surprise, fear, anger, sadness, and neutral.

Each emotion has been shown by fMRI to activate different portions of the brain. This is significant if a person is injured or has decreased activity level in a region of the brain, because it can change the ways they feel, act, and interact with others. It also can help to better understand why certain people have better visual recollection of memories, can recall certain information, even when in a sleeping or resting state.

This study consisted of two experiments. The first experiment included a large number of students recruited for a larger study by Ahmad Hariri, a professor of psychology and neuroscience. These healthy, young adult university students have been assessed on  a wide range of behavioral and biological traits. For this experiment, they were told to stare at a blank gray screen and to rest while not thinking of anything particular while being scanned by the fMRI.

The second experiment was with a smaller sample of just 22 participants. Before going into the fMRI, they rated how they felt emotionally in an unconstrained resting state. Once in the machine, they were told to rest and let their mind wander and to think freely with the blank screen occasionally letting them rate their current state of emotion. By the end of the experiment, they completed 40 trials of rating how they felt, which consisted of 16 different emotions they could choose from.

The researchers tried to quantify the occurrence of different spontaneous emotional states in resting brains.

At the end of both experiments, the researchers tested the brain scans with an algorithm that categorized emotional arousal and brain activity. They found distinct patterns of activity in these resting minds that seemed to match various emotional states the students had reported. Prior to this study, there had only been experiments which test to see how the brain is stimulated in active people in a non-resting state.

Although this experiment was successful and helped the researchers understand a lot more about the emotional states of the brain, there were some limitations as well. One of the main biases of the self-report experiment was the high percentage of students reporting that they were experiencing amusement (23.45%) and contentment (46.31%) which the researchers suppose was students putting forth a more positive image of themselves to others. Another possible bias is that brain patterns might vary depending on the emotional status of an individual. Emotional processes unfolding at both long and short time scales likely contribute to spontaneous brain activity.  

This study holds important clinical implications. Being able to ‘see’ emotional states in a resting brain would help us understand how important the feelings we experience are. With refinement, fMRI could become useful for diagnosing personality or mood disorders by showing us the brain areas being stimulated during certain periods of sadness, anger, and anxiety. Such applications could help with identifying emotional experiences in individuals with impaired awareness or compromised ability to communicate.

Guest post by Brynne O’Shea.

Are People Stuck with Their Political Views?

This is the fifth of eight blog posts written by undergraduates in PSY102: Introduction to Cognitive Psychology, Summer Term I 2019.

Whether you cheered or cried when Donald Trump was elected President, or if you stood in the blazing heat marching for women’s rights, your position on socio-political issues is important to you.  Would you ever change it?

Psychologists have found that people tend to hold onto their views, even when presented with conflicting evidence. Is it ever worth your time to argue with the opposition, knowing that they will not budge from their stance?

A 2013 protest in Brussels. Picture by M0tty via wikimedia commons

Researchers from Duke University explored the idea that people stand with their positions on political and social matters, even when presented with affirming or conflicting evidence.

But they also offer hope that knowing that these cognitive biases exist and understanding how they work can help lead to more rational decision-making, open debate of socio-political issues, and fact-based discussion.

The stubbornness of people’s views are based on a couple of concepts. “Resistance to belief-change” is the idea that people will stand with their original views and are unwilling to change them. This could be a result of a cognitive bias known as the “confirmation bias.” The bias is that people will favor evidence that supports their claim and deny evidence that refutes their position.

An example of this would be a person who supports Donald Trump rating an article about how he is doing a great job more favorably as opposed to a non-supporter who would use evidence that shows he is doing a bad job. Whether their position is a supporter or non-supporter, they will use evidence that supports their position and will overlook any conflicting evidence.

This can be shown through the following 2019 experiment performed by the Duke team, which was led by Felipe De  Brigard, a Duke assistant professor of philosophy and member of the Duke Institute for Brain Sciences.

This experiment started with a group of individuals across the spectrum of socio-economic and political interests. They were presented with five different socio-political issues: fracking, animal testing, drone strikes, standardized testing, and the gold standard. They started by reading background on the issue and then were to report any prior knowledge on these issues to eliminate people favoring information that they had previously encountered.

After reporting any prior knowledge, they were to make their decision and rate how confident they were in that decision. They were then tasked with evaluating only affirming evidence, only conflicting evidence, or evidence for both sides. After this, they gave their final decision about their stance on the issues.

The results showed that there was very little change in people’s positions after being presented with the evidence. For example, in the topic of fracking, about two in one-hundred people changed their position after being presented with affirming evidence. Also, when being presented with conflicting evidence, only one in five people changed their stance on the issue.

Similar changes were recorded with other issues and other sets of evidence. The results showed that receiving conflicting evidence caused people to change their position the most, but it was still a small percentage of people who changed their stance. This is significant because it shows how people are resistant to change because of their belief biases. Another interesting aspect is that participants rated evidence that affirmed their belief to be more favorable than those that conflicted it. This means they tended to use this evidence to support their stance and overlook conflicting evidence, which shows how cognitive biases, like the confirmation bias, play an important role in decision-making.

Cognitive bias affects how we make our decisions. More importantly, it entrenches our views and stops us from being open-minded. It is important to understand cognitive biases because they impact our choices and behavior. Becoming aware of biases like resistance to change, and the confirmation bias allows people to think independently and make decisions based off of rationale as well as emotion because they are aware of how these impact their decision making process.

Well, do you?

We expect to act rationally, making decisions that are in our best interest. However, this is often not true of humans. However, having adequate information, including understanding the impact of biases on decisionmaking, can lead humans to make better judgements. The next step in decision making research is to understand how people can change their entrenched positions to eliminate biases like the confirmation bias and bring more fact-based, open debate to socio-political issues.

To borrow from President Obama’s campaign slogan, is that change you can believe in?

Guest Post by Casey Holman, psychology major.

Move Your Eyes and Wiggle Your Ears

This is the fourth of eight blog posts written by undergraduates in PSY102: Introduction to Cognitive Psychology, Summer Term I 2019.

Research by Duke University neuroscientists has uncovered that the eardrums move when the eyes do. Even without sound, simply moving your eyes side to side causes the eardrums to vibrate.

Because the vibrations and eye movements seem to start simultaneously, it seems as if both processes are controlled by the same parts of the brain, suggesting the same motor commands control both processes, according to senior author Jennifer Groh of psychology and neuroscience.

A human ear.

Her team used rhesus monkeys and humans in an experiment that has given us new understanding of how the brain pairs hearing and seeing.

This research could help shed light on the brain’s role in experiencing outside stimuli, such as sounds or lights, or even in understanding hearing disorders. Scientists still don’t understand the purpose of eardrum movement, however.

The experiment fitted sixteen participants with microphones small enough to fit into the ear canals, but also sensitive enough to pick up the eardrums’ vibrations. It is known that the eardrum can be controlled by the brain, and these movements help control the influx of sound from the outside and also produce small sounds called “otoacoustic emissions.” Thus, it is important to measure vibrations, as this would signify the movement of the eardrum.

LED lights were presented in front of the participants and they were asked to follow the lights with their eyes as they shifted side to side.

Rhesus monkeys move their eardrums too!

This experiment was also replicated in three rhesus monkeys, using five of the six total ears between them. These trials were conducted in the same way as the humans.

The researchers concluded that whenever the eyes move, the eardrums moved together to shift focus to the direction of sight. Vibrations began shortly before and lasted slightly after the eye movements, further suggesting the brain controls these processes together. As eye movements get bigger, they cause larger vibrations.

These relationships highlight an important void in previous research, as the simultaneous and even anticipatory action of nearly 10 milliseconds of eardrum vibrations show that the brain has more control in making the systems work together, using the same motor commands. The information being sent to the eardrums, therefore, likely contains information received from the eyes.

Perhaps immersive headphones or movie theaters could also take advantage of this by playing sounds linked to the movements of eyes and eardrums to create a more “realistic” experience.

While the relationship between side to side eye movements was analyzed for their effect on eardrum movement, the relationship between up and down eye movements has yet to be discovered. Hearing disorders, like being unable to focus on a specific sound when many are played at once, are still being investigated. Scientists hope to further understand the relationship the brain has with the audio and visual systems, and the relationship they have with each other.

Guest post by Benjamin Fiszel, Class of 2022.

Your Brain Likes YOU Most

This is the third of eight blog posts written by undergraduates in PSY102: Introduction to Cognitive Psychology, Summer Term I 2019.

Imagine you’re at a party. You have a few friends there, but the rest of the people you don’t know. You fiddle with the beaded bracelet around your wrist, take a breath, relax your arms, and walk in. You grab some pretzels and a drink, and talk to this guy named Richard. He has a daughter, or a niece, or something like that. His moustache looked weird.

Okay, now quick question: would you remember if he was wearing a bracelet or not? Odds are you wouldn’t unless he had a bracelet like yours. In fact, it turns out that we recall things far better when those things concern ourselves.

Research has shown us that when it comes to what we notice, the quickest thing to grab our attention will be something we relate to ourselves, such as a picture of your own face compared to a picture of any other face. What still remains unknown however, is to what extent our prioritization of self plays an internal role in our processes of memory and decision making.

I am. Therefore I selfie.

To explore this, an international team of researchers led by Duke’s Tobias Egner analyzed the degree to which we prioritize self-related information by looking at how efficiently we encode and actively retrieve information we have deemed to concern ourselves.

They did this with a game. Research participants were shown three different colored circles that represented self, friend, and stranger. A pair of colored circles would appear in various locations on the screen, then vanish, followed by a black circle which appeared in the same or different location as one of the colored circles.

Participants were then asked if the black circle appeared at the same location where one of the colored circles had been. The responses were quite revealing.

People responded significantly quicker when the black circle was in the location of the circle labeled self, rather than friend or stranger. After variations of the experiment, the results still held. In one variation, the black circle would appear in the location of the self-circle only half as often as it did the others. But participants still recalled the quickest when the black circle appeared where their self-circle had been.

If the light blue dot is “you,” will you get the answer quicker?

With nothing but perception and reaction time, the process demonstrated that this is not a conscious decision we make, but an automatic response we have to information we consider our own.

The experiment demonstrated that when it comes to holding and retrieving information on demand, the self takes precedence. The interesting thing in this study however, is that the self-related stimulus in this experiment was not a picture of the person, or even the circle of their preferred color, it was simply the circle that the researchers assigned to the participant as self, it had nothing to do with the participants themselves. It was simply the participant’s association of that circle with themselves that made the information more important and readily available. It seems that to associate with self, is to bring our information closer.

The fact that we better recall things related to ourselves is not surprising. As creatures intended mostly to look after our own well-being, this seems quite an intuitive response by our working memory. However, if there is anything to take away from this experiment, it’s the significance of the colored circle labeled self. It was no different than any of the others circles, but merely making it ‘self’ improved the brain’s ability to recall and retrieve relevant information.

Simply associating things with ourselves makes them more meaningful to us.

Guest post by Kenan Kaptanoglu, Class of 2020.

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