Duke Research Blog

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

Digging Into Durham’s Eviction Problem

This is what 20 years of evictions looks like. It’s an animated heat map of Durham, the streets overlaid with undulating blobs of red and orange and yellow, like a grease stain.

Duke students in the summer research program Data+ have created a time-lapse map of the more than 200,000 evictions filed in Durham County since 2000.

Dark red areas represent eviction hotspots. These neighborhoods are where families cook their favorite meals, where children do their homework, where people celebrate holidays. They’re also where many people live one crisis away from losing their neighbors, or becoming homeless themselves.

Duke junior Samantha Miezio points to a single census tract along NC 55 where, in the wake of an apartment building sale, more than 100 households received an eviction notice in that spot in one month alone. It “just speaks to the severity of the issue,” Miezio said.

Miezio was part of a team that spent 10 weeks this summer mapping and analyzing evictions data from the Durham County Sheriff’s Office, thanks to an effort by DataWorks NC to compile such data and make it more accessible.

The findings are stark.

Every hour in Durham, at least one renter is threatened with losing their home. About 1,000 eviction cases were filed a month against tenants between 2010 and 2017. That’s roughly one for every 280 residents in Durham, where evictions per capita is one of the highest in the state and double the national average.

The data tell us that while Durham’s evictions crisis has actually improved from where it was a few years ago, stubborn hotspots persist, said team member Ellis Ackerman, a math major at North Carolina State University.

When the students looked at the data month by month, a few things stood out. For one, winter evictions are common. While some countries such as France and Austria ban winter evictions to keep from pushing people onto the street in the cold, in Durham, “January is the worst month by far,” said team member Rodrigo Araujo, a junior majoring in computer science. “In the winter months utility bills are higher; they’re struggling to pay for that.”

Rodrigo Araujo (Computer Science, 2021) talks about the Durham evictions project.

The team also investigated the relationship between evictions and rents from 2012 to 2014 to see how much they move in tandem with each other. Their initial results using two years’ worth of rent data showed that when rents went up, evictions weren’t too far behind.

“Rents increased, and then two months later, evictions increased,” Miezio said.

But the impacts of rising rents weren’t felt evenly. Neighborhoods with more residents of color were significantly affected while renters in white neighborhoods were not. “This crisis is disproportionately affecting those who are already at a disadvantage from historical inequalities,” Miezio said.

A person can be evicted for a number of reasons, but most evictions happen because people get behind on their rent. The standard guideline is no more than 30% of your monthly income before taxes should go to housing and keeping the lights on.

But in Durham, where 47% of households rent rather than own a home, only half of renters meet that goal. As of 2019 an estimated 28,917 households are living in rentals they can’t afford.

The reason is incomes haven’t kept pace with rents, especially for low-wage workers such as waiters, cooks, or home health aides.

Durham’s median rents rose from $798 in 2010 to $925 in 2016. That’s out of reach for many area families. A minimum wage worker in Durham earning $7.25/hour would need to work a staggering 112 hours a week — the equivalent of nearly three full-time jobs — to afford a modest two-bedroom unit in 2019 at fair market rent, according to a report by the National Low Income Housing Coalition.

Spending a sizable chunk of your income on housing means having less left over for food, child care, transportation, savings, and other basic necessities. One unexpected expense or emergency — maybe the kid gets sick or the car needs repairs, or there’s a cut back on hours at work — can mean tenants have a harder time making the rent.

“Evictions are traumatic life experiences for the tenants,” and can have ripple effects for years, Miezio said.

Tenants may have only a few days to pay what’s due or find a new place and move out. The Sheriff may come with movers and pile a person’s belonging on the curb, or move them to a storage facility at the tenant’s expense.

A forced move can also mean children must change schools in the middle of the school year.

Benefits may go to the wrong address. Families are uprooted from their social support networks of friends and neighbors.

Not every case filed ends with the tenant actually getting forced out, “but those filings can still potentially inhibit their ability to find future housing,” Miezio said. Not to mention the cost and hassle of appearing in court and paying fines and court fees.

Multiple groups are working to help Durham residents avoid eviction and stay in their homes. In a partnership between Duke Law and Legal Aid of North Carolina, the Civil Justice Clinic’s 2-year-old Eviction Diversion Program provides free legal assistance to people who are facing eviction.

“The majority of people who have an eviction filed against them don’t have access to an attorney,” Miezio said.

In a cost-benefit analysis, the team’s models suggest that “with a pretty small increase in funding to reduce evictions, on the order of $100,000 to $150,000, Durham could be saving millions of dollars” in the form of reduced shelter costs, hospital costs, plus savings on mental health services other social services, Ackerman said.

Ellis Ackerman, a senior math major from NC State University, talks about the Durham evictions research project.

Moving forward, they’re launching a website in order to share their findings. “I’ve learned HTML and CSS this summer,” said Miezio, who is pursuing an individualized degree program in urban studies. “That’s one of the things I love about Data+. I’m getting paid to learn.”

Miezio plans to continue the project this fall through an independent study course focused on policy solutions to evictions, such as universal right to counsel.

“Housing access and stability are important to Durham,” said Duke’s vice president for Durham affairs Stelfanie Williams. “Applied research projects such as this, reflecting a partnership between the university and community, are opportunities for students to ‘learn by doing’ and to collaborate with community leaders on problem-solving.”

Data+ 2019 is sponsored by Bass Connections, the Rhodes Information Initiative at Duke, the Social Science Research Institute, the Duke Energy Initiative, and the departments of Mathematics and Statistical Science.

Other Duke sponsors include DTECH, Science, Law, and Policy Lab, Duke Health, Duke University Libraries, Sanford School of Public Policy, Nicholas School of the Environment, Duke Global Health Institute, Development and Alumni Affairs, the Duke River Center, Representing Migrations Humanities Lab, Energy Initiative, Franklin Humanities Institute, Duke Forge, the K-Lab, Duke Clinical Research, Office for Information Technology and the Office of the Provost, as well as the departments of Electrical & Computer Engineering, Computer Science, Biomedical Engineering, Biostatistics & Bioinformatics and Biology.

Government funding comes from the National Science Foundation. Outside funding comes from Exxon Mobil, the International Institute for Sustainable Development (IISD), Global Financial Markets Center, and Tether Energy.

Post by Robin Smith, Duke Office of News and Communications
Post by Robin Smith

Do DNA Tests Sell Rosy Ideas About Race for Profit?

Earlier this year,  the online DNA testing company Ancestry.com faced a media firestorm and social media backlash after posting a controversial ad on its YouTube page.

The DNA testing company Ancestry.com took down its ad, “Inseparable,” in April 2019 in response to criticism that it romanticized slavery.

Titled “Inseparable,” the 30-second ad depicted a white man in the antebellum South asking an African-American woman to flee to the North with him. Before the woman can answer, the piece cuts to a tagline: “Only you can keep the story going. Uncover the lost chapters of your family history with Ancestry.” Many criticized the ad’s historical inaccuracy, showcasing a rosier portrayal of a complicated past. To extinguish flames, Ancestry completely pulled the ad from its platforms.

A recent Duke study of dozens of other ads across multiple DNA testing companies shows that this isn’t the only example of mixed messaging about race and identity from the world of genetic ancestry tests.

The tests are quite simple: order a kit, send off a saliva sample and receive an ethnicity estimate within weeks. A test taker’s ethnicity is broken down into percentages based off their DNA matches compared to a globally referenced DNA database. Kits can range in price from $79 to$400. Sales of DNA testing kits had reached 12 million people by 2017, as reported by ScienceLine.

As part of the six-week summer research program Story+, Duke students Dakota Douglas, Mona Tong and Madelyn Winchester analyzed the messaging in 90 video ads from the companies 23andMe, AncestryDNA and MyHeritageDNA to see what they promise consumers.

Many of the ads lured customers with promises of a newfound identity and possible family members, the team found. One Ancestry.com ad, entitled “Kyle,” depicts a customer whose childhood was steeped in German culture, but discovers as an adult that he is also part Scottish and Irish. He happily “traded in his lederhosen for a kilt,” completely forgoing his previous heritage and reducing a newly discovered culture to stereotypes.

“There were a lot of advertisements similar to that one,” said team member Mona Tong. “Many found a new identity embracing it fully despite a lack of any cultural connections.”

“Kyle” illustrates a phenomenon described in a 2018 study from the University of British Columbia, which found that people tended to “cherry-pick” the results, identifying more with certain ethnicities and cultures to appear different. Whites were more likely to see their results as “transformational” than their nonwhite counterparts.

“It’s not a bad idea to test your genes for medical reasons,” said Patricia Bass, the team’s project mentor. “However, these ads can be misleading by assuming that someone’s cultural and racial heritage are determined by genes.”

While the majority of subjects featured within the ads were white, the few ads that featured people of color often glossed over the complicated history of someone’s lineage or conveniently left out difficult topics. Ancestry’s “Anthem” ad detailed historical reenactments of an African tribal women, prohibition gangsters, a man fleeing England for America and Native Americans somberly heading to a new land. A voiceover speaks with inspiration ending with a shot of a biracial woman.

In marketing the idea that we are all one, the ads fetishized mixed-race subjects, while ignoring the genocide and displacement of people, the team found.

The team hopes future research will further examine the impact of these ads on people’s view of identity. Importantly, one could note if there were any focus groups to test these ads before release.

“It furthers the idea of colorblindness,” Tong said. “It assumes that relationships are contingent upon common ancestry and genes.”

“In a way, companies are trying to help by focusing on the interconnectivity and commonalities between people,” Tong said. “But it hurts more than it helps.”

Story+ is a six-week undergraduate research program offered through the John Hope Franklin Humanities Institute and Bass Connections, with support from the Duke University Libraries and Versatile Humanists at Duke.

By Deja Finch

Science in haiku: // Interdisciplinary // Student poetry

On Friday, August 2, ten weeks of research by Data+ and Code+ students wrapped up with a poster session in Gross Hall where they flaunted their newly created posters, websites and apps. But they weren’t expecting to flaunt their poetry skills, too! 

Data+ is one of the Rhodes Information Initiative programs at Duke. This summer, 83 students addressed 27 projects addressing issues in health, public policy, environment and energy, history, culture, and more. The Duke Research Blog thought we ought to test these interdisciplinary students’ mettle with a challenge: Transforming research into haiku.

Which haiku is your
favorite? See all of their
finished work below!

Eric Zhang (group members Xiaoqiao Xing and Micalyn Struble not pictured) in “Neuroscience in the Courtroom”
Maria Henriquez and Jake Sumner on “Using Machine Learning to Predict Lower Extremity Musculoskeletal Injury Risk for Student Athletes”
Samantha Miezio, Ellis Ackerman, and Rodrigo Aruajo in “Durham Evictions: A snapshot of costs, locations, and impacts”
Nikhil Kaul, Elise Xia, and Mikaela Johnson on “Invisible Adaptations”
Karen Jin, Katherine Cottrell, and Vincent Wang in “Data-driven approaches to illuminate the responses of lakes to multiple stressors”.

By Vanessa Moss

Global Health is Local Too

DGHI interns, left to right: Gabrielle Zegers (C’19), Ashley Wilson (C’20), and Rachel Baber (C’20).

When Duke senior Rachel Baber began her freshman year, she was under the impression that legitimate research had to involve a white lab coat and a microscope.

But this summer she worked to study human health without a pipette in sight, instead spending her time in a computer lab, which was empty besides her and two fellow interns. A few yards away from her shared workspace, blue metal double doors swing into a linoleum-floored cafeteria.

As she sits at a table near the entrance, dozens of men and women walk past in ones and twos, some with oil smeared on their jeans and others pushing carts with cleaning supplies, talking with one another and nodding to acknowledge Baber.

She’s been working all summer at the Triangle Residential Options for Substance Abusers, Inc., better known as TROSA, and everyone passing is a resident.

TROSA is acclaimed for their whole-person approach to substance-abuse recovery and trauma resiliency, with multi-year programming that provides treatment, educational opportunities, and vocational training for their clients. TROSA has been providing services for 25 years and, like most non-profit organizations, they have a running list of projects with limited number of staff hours to commit to them.

“It’s not that they’re back-burner issues,” explains Karen Kelley, the Chief Program Officer at TROSA. “It’s just that we don’t have enough front burners.”

This summer, Duke’s undergraduates stepped in to provide a little more stove space for TROSA’s needs.

Duke’s Global Health Institute (DGHI) requires all students to spend one summer in a research training program, which associate professor Sumi Ariely believes is a vital opportunity for students to “work deeply with a community partner and their vision, and to help disparities or inequities in their community.”

Program options range from looking at health impacts of gold mining in Ghana to screening for glaucoma in Honduras, but 2019 was DGHI’s first season offering TROSA as a research site, opening new avenues for students to give back to the Durham community.

“We have a responsibility to our neighbors,” Ariely says. “‘Global is Local’ holds two meanings. As a geographic term, it focuses on the Triangle or Durham area. It also holds philosophical value. We in high-resource areas don’t have all the answers, and entering global arenas flaunting our ‘solutions’ is just hubris,” she adds. “Working to solve pockets of deep inequalities in our state and our country allows for multi-directional learning.  Local is Global acknowledges that we are all fundamentally the same and in it together.”

Duke University and TROSA have had a long history of collaboration. TROSA moving services are a common sight on Duke’s campus, and Duke Health also contracts with providers who work on-site at TROSA to give primary, behavioral health, and psychological care for clients.

Having three DGHI interns allowed TROSA to begin answering questions that they’d long been speculating about: How does cigarette smoking impact the community as a rehabilitation center? How could the program integrate sustainable practices like recycling and composting on an institutional scale? How accessible are the classes that TROSA offers residents and how do they affect resident growth and recovery?

 Baber spent her time tackling the last question, first classifying the full curriculum of TROSA’s courses into three major categories: Therapeutic, vocational, and educational. Looking at past courses that residents had taken, she began the process of setting course standards for residents – what number of therapeutic courses are expected to be completed at nine months into the program compared to 15 months, for example.

This number-crunching project also provided an opportunity for the administration to reflect on course access. Baber was able to find some patterns in curriculum, like how most residents register for more classes as they advance through the program, and how female residents often register for more therapeutic courses than men.

“I’d love to qualitatively look at residents’ impressions of the classes,” Baber explains. “Some people really enjoy a certain category of courses, while others benefit more from working on a job and dealing with problems as they come up.” Baber envisions that question, along with identifying which classes have the highest graduation rate and asking why that is, as possible projects for future interns.

Rebecca Graves, TROSA’s Director of Clinical Operations, sees data and demographic review like this as a critical means of assessment and improvement. “As a nonprofit, we use a quarterly review to pay close attention to demographic changes. If 80% of applicants were female and only 20% of our population was women, we’d need to review — What’s keeping people out of the door? Are we inhibitive in some way?”

After working with often-incomplete data, Baber and fellow interns Ashley Wilson (C’20) and Gabrielle Zegers (C’19) were able to realize what information is missing, refine what TROSA should keep collecting, and find what they could from the data they did have.

“Check them off as huge successes,” Graves reiterates. “They’re making marked achievements, finding new data, extrapolating new information, and creating new policies here. They all took ownership as self-motivated researchers, and my dream is that they’d all stay.”

Beyond working on their assigned projects, the three students were eager to invest themselves in the TROSA community, attending a dance with new women in the program, volunteering at the TROSA thrift store on weekends, volunteering at the medical center, and helping with GED tutoring each Tuesday evening.

“Getting to learn from residents about their recovery and what they’re doing to help themselves has been the best part of this job,” Baber says. In global health, students often face large and looming statistics surrounding the opioid epidemic. “It’s easy to dehumanize that problem. It’s easy in global health to think ‘Oh, these numbers are so huge. I’ll never make a difference.’ But talking to individuals personalizes the matter, it makes you realize that positive change can happen.”


For more information about TROSA, visit: www.trosainc.org


By Vanessa Moss

An Undergraduate Student Grapples with Morality

Existential speculations are normal part of college, and parents shouldn’t worry too much if their child calls home freshman year to speculate on the writings of Immanuel Kant or Sigmund Freud with them. It’s all part of growing up.

But for Shenyang Huang (C’20), these existential questions aren’t just pastimes: They’re work.

As a neuroscience major and a participant in Duke’s Summer Neuroscience Program, Huang has spent eight weeks of his summer in the Imagination and Modal Cognition laboratory researching under Dr. Felipe De Brigard, a three-in-one professor of philosophy, psychology, and neuroscience. Huang has been working at the intersection of those fields with PhD student Matt Stanley to explore some hefty questions about morality and memory.

Shenyang Huang is a rising senior Neuroscience student at Duke. (Image provided by Huang)

The team is grappling with our past mistakes, and how they’ve impacted who we are today. Specifically, how do we remember moments when we behaved immorally? And how do those moments shape the way we think of ourselves?

These questions have been approached from various angles in different studies. One such study, published in 2016 by Maryam Kouchaki and Frencesca Gino, claims that “Memories of unethical actions become obfuscated over time.” Or rather, we forget the bad things we’ve done in the past. According to their study, it’s a self-preservation method for our current concepts of self-worth and moral uprightness.

“I was surprised when I read the Kouchaki and Gino study,” Huang explains. “They claim that people try to forget the bad things they’d done, but that doesn’t feel right. In my life, it’s not right.”

In their two-part study, Stanley and Huang surveyed nearly 300 online participants about these moments of moral failure. They reported memories ranging from slightly immoral events, like petty thievery and cheating on small assignments, to highly immoral incidences, like abusing animals or cheating on significant others. Through questionnaires, the team measured the severity of each incident, how vividly the person recollected the experience, how often the memory would bubble to consciousness on its own, how they emotionally responded to remembering, and how central each event was to the subject’s life.

Their preliminary results resonate more with Huang: Highly immoral actions were recalled more vividly than milder transgressions, and they were generally considered more central in subjects’ life narratives.

“Moral memories are central to one’s sense of self,” Huang says, “and the other paper didn’t discuss centrality in one’s life at all.”

Felipe DeBrigard is an assistant professor of philosophy and a member of the Duke Institute for Brain Sciences. (Les Todd, Duke Photo)

Though contradictory to what Kouchaki and Gino found, the findings have a firm foundation in current psychology literature, De Brigard says. “There are a lot of studies backing the contrary [to Kouchaki and Gino], including research on criminal offenses. People who have committed crimes of passion are known to suffer from a kind of moral PTSD — they constantly relive the event.”

Huang’s study is only one branch of research in a comprehensive analysis of morality and memory De Brigard is exploring now, with the help from the six graduate and eight undergraduate students operating out of his lab.

“Working in a lab with philosophers, psychologists, and neuroscientists, you see different approaches to the same overarching problem,” Huang says. And as he begins to consider PhD programs in neuroscience, this interdisciplinary exposure is a huge asset.

“It’s helpful and inspiring — I can’t take every class, but I can sit and overhear conversations in the lab about philosophy or psychology and learn from it. It widens my perspective.”


by Vanessa Moss

Nature Shows a U-Turn Path to Better Solar Cells

The technical-sounding category of “light-driven charge-transfer reactions,” becomes more familiar to non-physicists when you just call it photosynthesis or solar electricity.

When a molecule (in a leaf or solar cell) is hit by an energetic photon of light, it first absorbs the little meteor’s energy, generating what chemists call an excited state. This excited state then almost immediately (like trillionths of a second) shuttles an electron away to a charge acceptor to lower its energy. That transference of charge is what drives plant life and photovoltaic current.

A 20 Megawatt solar farm ( Aerial Innovations via wikimedia commons)

The energy of the excited state plays an important role in determining solar energy conversion efficiency. That is, the more of that photon’s energy that can be retained in the charge-separated state, the better. For most solar-electric devices, the excited state rapidly loses energy, resulting in less efficient devices.

But what if there were a way to create even more energetic excited states from that incoming photon?

Using a very efficient photosynthesizing bacterium as their inspiration, a team of Duke chemists that included graduate students Nick Polizzi and Ting Jiang, and faculty members David Beratan and Michael Therien, synthesized a “supermolecule” to help address this question.

“Nick and Ting discovered a really cool trick about electron transfer that we might be able to adapt to improving solar cells,” said Michael Therien, the William R. Kenan, Jr. Professor of Chemistry. “Biology figured this out eons ago,” he said.

“When molecules absorb light, they have more energy,” Therien said. “One of the things that these molecular excited states do is that they move charge. Generally speaking, most solar energy conversion structures that chemists design feature molecules that push electron density in the direction they want charge to move when a photon is absorbed. The solar-fueled microbe, Rhodobacter sphaeroides, however, does the opposite. What Nick and Ting demonstrated is that this could also be a winning strategy for solar cells.”

Ting Jiang
Nick Polizzi

The chemists devised a clever synthetic molecule that shows the advantages of an excited state that pushes electron density in the direction opposite to where charge flows. In effect, this allows more of the energy harvested from a photon to be used in a solar cell. 

“Nick and Ting’s work shows that there are huge advantages to pushing electron density in the exact opposite direction where you want charge to flow,” Therien said in his top-floor office of the French Family Science Center. “The biggest advantage of an excited state that pushes charge the wrong way is it stops a really critical pathway for excited state relaxation.”

“So, in many ways it’s a Rube Goldberg Like conception,” Therien said. “It is a design strategy that’s been maybe staring us in the face for several years, but no one’s connected the dots like Nick and Ting have here.”

In a July 2 commentary for the Proceedings of the National Academy of Sciences, Bowling Green State University chemist and photoscientist Malcom D.E. Forbes calls this work “a great leap forward,” and says it “should be regarded as one of the most beautiful experiments in physical chemistry in the 21st century.”

Here’s a schematic from the paper.
(Image by Nick Polizzi)

CITATION: “Engineering Opposite Electronic Polarization of Singlet and Triplet States Increases the Yield of High-Energy Photoproducts,” Nicholas Polizzi, Ting Jiang, David Beratan, Michael Therien. Proceedings of the National Academy of Sciences, June 10, 2019. DOI: 10.1073/pnas.1901752116 Online: https://www.pnas.org/content/early/2019/07/01/1908872116

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.

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