Duke Research Blog

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

Category: Neuroscience Page 1 of 11

How Many Neuroscientists Does it Take to Unlock a Door?

Duke’s Summer Neuroscience Program kicked off their first week of research on June 4 with a standard morning meeting: schedules outlined, expectations reiterated, students introduced. But that afternoon, psychology and neuroscience professor Thomas Newpher and undergraduate student services coordinator Tyler Lee made the students play a very unconventional get-to-know-you game — locking them in a room with only one hour to escape.

Not the usual team building activity: Students in Duke’s 8-week Summer Neuroscience Program got to know each other while locked in a room.

Bull City Escape is one of a few escape rooms in the Triangle, but the only one to let private groups from schools or companies or families to come and rent out the space exclusively. Like a live-in video game, you’re given a dramatic plot with an inevitably disastrous end: The crown jewels have been stolen! The space ship is set to self-destruct! Someone has murdered Mr. Montgomery, the eccentric millionaire! With minutes to go, your rag-tag bunch scrambles to uncover clues to unlock locks that yield more clues to yet more locks and so on, until finally you discover the key code that releases you back to the real world.

This summer’s program dips into many subfields, in hopes of pushing the the 16 students (most of them seniors) toward an honors thesis. According to Newpher, three quarters of the senior neuroscience students who participated in the 2018 SNP program graduated with distinction last May.

From “cognitive neuro” that addresses how behavior and psychology interacts with your neural network, to “translational neuro” which puts neurology in a medical context, to “molecular and cellular neuro” that looks at neurons’ complex functions, these students are handling subjects that are not for the faint of heart or dim of mind.

But do lab smarts carry over when you’re locked in a room with people you hardly know, a monitor bearing a big, red timer, blinking its way steadily toward zero?

Apparently so. The “intrepid team of astronauts” that voyaged into space were faced with codes and locks and hidden messages, all deciphered with seven minutes left on the clock, while the “crack-team of detectives” facing the death of Mr. Montgomery narrowly escaped, with less than a minute to spare. At one point, exasperated and staring at a muddled bunch of seemingly meaningless files, a student looked at Dr. Newpher and asked, “Is this a lesson in writing a methods section?”

The Bull City Escape website lists creative problem-solving, focus, attention to detail, and performance under pressure as a few of the skills a group hones by playing their game — all of which are relevant to this group of students, many of whom are pre-med. But hidden morals about clarity and strength-building aside, Newpher picked the activity because it allows different sides of people’s personalities to come out: “When you’re put in that stressful environment and the clock is ticking, it’s a great way to really get to know each other fast.”

By Vanessa Moss
By Vanessa Moss

The Adolescent Brain Isn’t so Bad, Really

Adriana Galván, PHD (Photo from the Duke Center for Cognitive Neuroscience Colloquium Series, DIBS)

More often than not, teenagers are portrayed in the media as troublesome, emotionally reactive, and difficult to deal with. They are widely considered to be risk-takers, and prone to making poor choices.

But is taking risks necessarily a bad thing? Should adolescents be seen as bad people? Adriana Galván, PHD, doesn’t think so.

Galván is a neuroscientist and professor at UCLA, where she studies sleep, emotion, learning, stress, and decision-making in the adolescent brain. She came to Duke on Friday, April 5 as part of the DIBS Center for Cognitive Neuroscience’s Colloquium Series.

Humans have an extended period of adolescence, because our brains take a very long time to complete development, Galván said. Adolescence is currently defined as the period between the onset of puberty and the end of developmental plasticity. During this time, teen brains are constantly changing, and these physical changes are linked to socioemotional changes in behavior.

The Brain’s Reward System: meso-limbic pathway shown in green (Photo from WikiCommons: Oscar Arias-Carrión1, Maria Stamelou, Eric Murillo-Rodríguez, Manuel Menéndez-González and Ernst Pöppel)

One of the most prominent differences between adolescent and adult brains can be found in the brain’s reward system. Research has shown that adolescents have higher levels of activation in the mesolimbic system and ventral striatum regions of the brain, areas that are very important in reward processing.

Galván believes that this greater reward system excitability in teenagers may explain why they engage in more risky behavior than adults.

A study done by Galván and her former student, Emily Barkley-Levenson, investigated the stereotype of risk-taking in adolescents. Sure enough, when tested against adults in a gambling game, adolescents were more likely to take risks. However, a closer look at the data suggests that this might not be such a bad thing.

For disadvantageous and neutral gambles, adolescents didn’t differ from adults at all. But when it came to advantageous gambles, adolescents were far more likely than adults to accept the risk. This suggests that risk-taking behavior in teens might actually be adaptive, and put young people at an advantage when it comes to making the choices that lead to innovation and discovery.

Adolescents were also shown to exhibit better learning from outcomes than adults. Adolescence is a period of time where young people are constantly receiving feedback from their environment, and learning about the world around them from social interactions and relationships.

Another of Galván’s students, Kaitlyn Breiner, found that adolescents experienced high levels of emotional distress when their expectations of social feedback were violated. This was true regardless of whether the participants were receiving positive or negative unexpected feedback; they were just as distressed by an unexpected compliment as they were by an unexpected insult. Galván hypothesizes this is because relief is a very powerful emotion, and adolescent participants were looking to find comfort in a validation of their beliefs about their social relationships. It’s comforting to feel like your interpretation of the social world is correct, especially during the shifting world of adolescence.

Adolescents learn about their world through social interactions with friends (Photo from Wikimedia Commons: Glenn Waters)

Galván and her team have also investigated the role of mesolimbic activation in mediating distress.

Following the 2016 US Presidential election, participants in Los Angeles were asked if they felt personally affected by the election. The research team then measured the activation in their nucleus accumbens (a region of the mesolimbic system that plays a role in reward) and looked for symptoms of depression. Of those who reported feeling affected by the outcome of the election, Galván found that people with high activation in their nucleus accumbens had less depressive symptoms than those with low activation in this area. This suggests that high activation of the reward system plays a role in mediating depression. If adolescent brains experience these higher levels of reward system activation, might this protect them from depression?

The bottom line is, adolescents are not bad people, and they aren’t stupid either. In some ways, they may even be smarter than adults. Teens are better at learning from outcomes, more likely to take advantageous risks, and they experience higher levels of activation in their reward system, which could have important implications for resilience. The research shows that teenagers are far more capable – and smarter – than the world believes. Let’s give them a little more credit.

Post by Anne Littlewood, Trinity ’21

The Costs of Mental Effort

Every day, we are faced with countless decisions regarding cognitive control, or the process of inhibiting automatic or habitual responses in order to perform better at a task.

Amitai Shenhav, PhD, of Brown University, and his lab are working on understanding the factors that influence this decision making process. Having a higher level cognitive control is what allows us to complete hard tasks like a math problem or a dense reading, so we may expect that the optimal practice is to exert a high level of control at all times.

Shenhav’s lab explores motivation and decision making related to cognitive control.

Experimental performance shows this is not the case: people tend to choose easier over hard tasks, require more money to complete harder tasks, and exert more mental effort as the reward value increases. These behaviors all suggest that the subjects’ automatic state is not to be at the highest possible level of control.

Shenhav’s research has centered around why we see variation in level of control. Because cognitive control is a costly process, there must be a limit to how much we can exert. These costs can be understood as tradeoffs between level of control and other brain functions and consequences of negative affective changes related to difficult tasks, like stress.

To understand how people make decisions about cognitive control in real time, Shenhav has developed an algorithm called the Expected Value of Control (EVC) model, which focuses on how individuals weigh the costs and benefits of increasing control.

Employing this model has helped Shenhav and his colleagues identify situations in which people are likely to choose to invest a lot of cognitive control. In one study, by varying whether the reward was paired only with a correct response or was given randomly, Shenhav simulated variability in efficacy of control. They found that people learn fairly quickly whether increasing their efforts will increase the likelihood of earning the reward and adjust their control accordingly: people are more likely to invest more effort when they learn that there is a correlation between their own effort and the likelihood of reward than when rewards are distributed independent of performance.

Another study explored how we adjust our strategies following difficult tasks. Experiments with cognitive control often rely on paradigms like the Stroop task, where subjects are asked to identify a target cue (color) while being presented with a distractor (incongruency of the word with its text color). Shenhav found that when subjects face a difficult trial or make a mistake, they adjust by decreasing attention to the distractor.

The Stroop task is a classic experimental design for understanding cognitive control. Successful completion of Stroop task 3 requires overriding your reflex to read the word in cases where the text and its color are mismatched.

A final interesting finding from Shenhav’s work tells us that part of the value of hard work may be in the work itself: people value rewards following a task in a way that scales to the effort they put into the task.

Zapping Your Brain Is Dope

Emerging technology has created a new doping technique for athletic performance that is, as of now, perfectly legal.

Coined “neuro-doping,” this method sends electric current through one’s brain to facilitate quicker learning, enhanced muscular strength, and improved coordination. Use of this electronic stimulus has taken off in the sports world as a replacement for other doping methods banned by the World Anti-Doping Agency (WADA). Because it’s relatively new, WADA has yet to establish rules around neuro-doping. Plus, it’s virtually undetectable. Naturally, a lot of athletes are taking advantage of it.

Image result for doping

One specific method of neuro-doping is known as Transcranial Direct-Current Stimulation (tDCS). It works by sending a non-invasive and painless electrical current through the brain for around three to 20 minutes, in order to excite the brain’s cortex, ultimately increasing neuroplasticity (Park). This can be done commercially via a headset like device for $200.

Image result for transcranial direct current stimulation headset
The Halo Sport

Weight lifters, sprinters, pitchers, and skiers are just some of many types of athletes who can benefit from tCDS. By practicing with these headphones on, new neural pathways are constructed to help their bodies achieve peak performance. Dr. Greg Appelbaum, director of Opti Lab and the Brain Stimulation Research Center, says it’s especially useful for athletes where technique and motor skills triumph — such as a sprinter getting out of the blocks or an Olympic ski jumper hanging in the air. Top-tier athletes are pushing that fine limit of what the human body can accomplish, but neuro-doping allows them to take it one step further.

Neuro-doping has other applications, too. Imagine insanely skilled Air Force pilots, surgeons with exceptionally nimble hands, or soldiers with perfect aim. tCDS is being used to make progress in things like Alzheimer’s and memory function because of its impact on cognitive functioning in the forms of increased attention span and memory. You could even learn the guitar faster.

In this sort of context, it’s a no brainer that neuro-doping should be taken advantage of. But how ethical is it in sports?

The precedent for WADA to ban a substance or technique has been based on meeting two of the following three criteria: (1) drugs or tools that likely enhance performance to secure a winning edge; (2) drugs or tools that place athletes’ health at risk; (3) any substances or techniques that ruin the “spirit-of-sport” (Park). Lots of research has shown tCDS is pretty legit. As for health risks, tCDS is still in the experimental stage, so not much can be said about its side effects. Ethically, it causes a lot of controversy.

Many issues come into play when thinking about allowing athletes to neuro-dope. Given its similarities with other popular drugs, tCDS could introduce unfair advantages. Furthermore, not everyone may have access to the technology, and not everyone may want to use it. However, it’s important to note that sports already have unfair advantages. Access to things like proper coaching and nutrition may not be a reality for everyone. Sports are just inherently competitive.

Back when baseball players doped, it was awesome to watch them crush balls out of the park. Reintroducing performance enhancement through tCDS could mean we start seeing mountain bikers launching insane air and world records being smattered. The human body could achieve newfound heights.

Are the benefits worth it? Does neuro-doping ruin the “spirit of the sport?” Regardless of these important questions, tCDS is a fascinating scientific discovery that could make a difference in this world. So, what do you think?

Will Sheehan
Post by Will Sheehan

Park, Cogent Social Sciences (2017), 3: 1360462
https://doi.org/10.1080/23311886.2017.1360462

Dolphin Smarts

Imagine you are blindfolded and placed into a pool of water with a dolphin. The dolphin performs a movement, such as spinning in a circle, or swimming in a zig-zag pattern, and your task is to imitate this movement, without having seen it. Ready, go. 

Sound impossible? While it may not be possible for a human to do this with any accuracy, a dolphin would have no problem at all. When cognitive psychologist and marine mammal scientist Kelly Jaakkola gave this task to the dolphins at the Dolphin Research Center in Florida, they had no problem at all copying a human’s behavior. So how did they do it? Jaakkola thinks they used a combination of active listening and echolocation.

How smart are dolphins? (Photo from Wikimedia Commons: Stuart Burns)

Humans love to claim the title of “smartest” living animal. But what does this mean? How do we define intelligence? With a person’s GPA? Or SAT score? By assigning a person a number that places him or her somewhere on the scale from zero to Einstein? 

Honestly, this is problematic. There are many different types of intelligence that we forget to consider. For example, Do you know that five is less than seven? Can you remember the location of an object when you can’t see it? Can you mimic a behavior after watching it? Are you capable of cooperating to solve problems? Can you communicate effectively? All of these demonstrate different intelligent skills, many of which are observed in dolphins.

Needless to say, dolphins and humans are entirely different creatures. We have different body plans, different ways of interacting with the world, and different brains. It has been 90 million years since we shared a common ancestor, which is why the things we do have in common are so fascinating to researchers. 

Like us, dolphins understand ordinality. When presented with two novel boards with different numbers of dots, dolphins at the Dolphin Research Center chose the smaller number 83 percent of the time. But unlike us, they weren’t counting to solve this problem. When they were shown boards that represented consecutive numbers, the dolphins struggled, and often failed the task.

Similar to humans, dolphins understand that when objects are hidden from view, they still exist. At the Dolphin Research Center, they could easily remember the location of toy when a trainer hid it inside a bucket. However, unlike humans, dolphins couldn’t infer the movement of hidden objects. If the bucket was moved, the dolphins didn’t understand that the toy had moved with it.

Dr. Jaakkola presents to a packed room of Duke students

While they may not be physicists, Jaakkola has shown that dolphins are stellar cooperators, and amazing at synchronous tasks. When asked to press an underwater button at the same time as a partner, the dolphins pushed their buttons within 0.37 milliseconds of each other, even when they started at different times. As the earlier example shows, dolphins can also imitate incredibly well, and this skill is not limited to mimicking members of their own species. Even though humans have an entirely different body plan, dolphins can flexibly use their flipper in place of a hand, or their tail in place of legs, and copy human movements.

It is believed that dolphins evolved their smarts so that they could navigate the complex social world that they live in. As the researchers at the Dolphin Research Center have shown, they possess a wide array of intelligent abilities, some similar to humans and others entirely different from our own. “Dolphins are not sea people,” Jaakkola warned her audience, but that’s not to discount the fact that they are brilliant in their own way. 

Style Recommendations From Data Scientists

A combination of data science and psychology is behind the recommendations for products we get when shopping online.

At the intersection of social psychology, data science and fashion is Amy Winecoff.

Amy Winecoff uses her background in psychology and neuroscience to improve recommender systems for shopping.

After earning a Ph.D. in psychology and neuroscience here at Duke, Winecoff spent time teaching before moving over to industry.

Today, Winecoff works as a senior data scientist at True Fit, a company that provides tools to retailers to help them decide what products they suggest to their customers.

True Fit’s software relies on collecting data about how clothes fit people who have bought them. With this data on size and type of clothing, True Fit can make size recommendations for a specific consumer looking to buy a certain product.    

In addition to recommendations on size, True Fit is behind many sites’ recommendations of products similar to those you are browsing or have bought.

While these recommender systems have been shown to work well for sites like Netflix, where you may have watched many different movies and shows in the recent past that can be used to make recommendations, Winecoff points out that this can be difficult for something like pants, which people don’t tend to buy in bulk.

To overcome this barrier, True Fit has engineered its system, called the Discovery engine, to parse a single piece of clothing into fifty different traits. With this much information, making recommendations for similar styles can be easier.

However, Winecoff’s background in social psychology has led her to question how well these algorithms make predictions that are in line with human behavior. She argues that understanding how people form their preferences is an integral part of designing a system to make recommendations.

One way Winecoff is testing how true the predictions are to human preferences is employing psychological studies to gain insight in how to fine-tune mathematical-based recommendations.

With a general goal of determining how humans determine similarity in clothes, Winecoff designed an online study where subjects are presented with a piece of clothing and told the garment is out of stock. They are then presented with two options and must pick one to replace the out-of-stock item. By varying one aspect in each of the two choices, like different color, pattern, or skirt length, Winecoff and her colleagues can distinguish which traits are most salient to a person when determining similarity.

Winecoff’s work illustrates the power of combining algorithmic recommendations with social psychological outcomes, and that science reaches into unexpected places, like influencing your shopping choices.  

Post by undergraduate blogger Sarah Haurin
Post by undergraduate blogger Sarah Haurin

Bias in Brain Research

Despite apparent progress in achieving gender equality, sexism continues to be pervasive — and scientists aren’t immune.  

In a cyber talk delivered to the Duke Institute for Brain Sciences, professor Cordelia Fine of the University of Melbourne highlighted compelling evidence that neuroscientific research is yet another culprit of gender bias.

Fine says the persistent idea of gender essentialism contributes to this stagnation. Gender essentialism describes the idea that men and women are fundamentally different, specifically at a neurological level. This “men are from Mars, women are from Venus” attitude has spread from pop culture into experimental design and interpretation.

However, studies that look for sex differences in male and female behavior tend to show more similarities than differences. One study looked at 106 meta-analyses about psychological differences between men and women. The researchers found that in areas as diverse as temperament, communication styles, and interests, gender had a small effect, representing statistically small differences between the sexes.

Looking at fMRI data casts further doubt on how pronounced gender differences really are. A meta-analysis of fMRI studies investigating functional differences between men and women found a large reporting bias. Studies finding brain differences across genders were overrepresented compared to those finding similarities.

Of those small sex differences found in the central nervous system, Fine points out how difficult it is to determine their functional significance. One study found no difference between men and women in self-reported emotional experience, but found via fMRI that men exhibited more processing in the prefrontal cortex, or the executive center of the brain, than women. Although subjective experience of emotion was the same between men and women, the researchers reported that men are more cognitive, while women are more emotional.

Fine argues that conclusions like this are biased by gender essentialism. In a study she co-authored, Fine found that gender essentialism correlates with stronger belief in gender stereotypes, that gender roles are fixed, and that the current understanding of gender does not need to change.

When scientists allow preconceived notions about gender to bias their interpretation of results, our collective understanding suffers. The best way to overcome these biases is to ensure we are continuing to bring more and more diverse voices to the table, Fine said.

Fine spoke last month as part of the Society for Neuroscience Virtual Conference, “Mitigating Implicit Bias: Tools for the Neuroscientist.” The Duke Institute for Brain Sciences (@DukeBrain) made the conference available to the Duke community.  

Post by undergraduate blogger Sarah Haurin
Post by undergraduate blogger Sarah Haurin

The Importance of Moms

Emily Bray, Ph.D., might have the best job ever. Since earning her bachelor’s at Duke in 2012, she has been researching cognitive development in puppies, which basically means she’s spent the last seven years playing with dogs. If that’s not success, I don’t know what is.

Last Friday marked the 10th birthday of Duke’s Canine Cognition Center, and the 210th birthday of Charles Darwin. To celebrate, Brian Hare, Ph.D., invited former student Bray back to campus to share her latest research with a new generation of Duke undergraduates. The room was riveted — both by her compelling findings and by the darling photos of labs and golden retrievers that accompanied each slide.

Dr. Emily Bray shows photos of her study participants

During her Ph.D. program at the University of Pennsylvania, Bray worked with Robert Seyfarth, Dorothy Cheney, and James Serpell to investigate the effects of mothering on puppy development. For her dissertation, she studied a population of dog moms and their puppies at The Seeing Eye, Inc. The Seeing Eye is one of the oldest and largest guide dog schools in the U.S. They have been successfully raising and training service dogs for the blind since 1929, but like most things, it is still an imperfect science. Approximately half of the puppies bred at The Seeing Eye fail out of program. A dog that completes service training at The Seeing Eye represents two years of intensive training and care, and investing so much time and money into a dog that might eventually fail is problematic. Being able to predict the outcomes of puppies would save a lot of wasted time and energy, and Emily Bray has been doing just this.

What makes a good dog mom? (Photo from Dirk Vorderstraße, from Wikimedia Commons)

Through her work at The Seeing Eye, Bray found that, similar to humans, dogs have several types of mothering styles. She discovered that dog moms tend to fall somewhere on the spectrum from low to high maternal involvement. Some of the moms were very involved with their puppies, and seldom left their side. These hovering moms had high levels of cortisol, and became quite stressed when separated briefly from a puppy. They coddled their children, and often nursed from a laying down position, doing everything they could to make life easy for their babies. On the other side of the spectrum, Bray also observed moms that displayed much more relaxed mothering. They often took personal time, and let their puppies fend for themselves. They were more likely to nurse while sitting or standing up, which made their children work harder to feed. They were less stressed when separated from a puppy, and also just had generally lower levels of cortisol. Sound like bad parenting? Believe it or not, this tough love actually resulted in more successful puppies.

Duke’s very own assistance dogs in training!

As the puppies matured, Bray conducted a series of cognitive and temperament tests to determine if maternal style was associated with a certain way of thinking in the puppies. Turns out, dogs who experienced high maternal care actually performed much worse on the tests than dogs who were shown tough love when they were young. At The Seeing Eye graduation, it was also determined that high maternal care and ventral nursing was associated with failure. Puppies that were over-mothered were more likely to fail as service dogs.

Her theory is that tough love raises more resilient puppies. When mom is always around, the puppies don’t get the chance to experience small stressors and learn how to deal with challenge. The more relaxed moms actually did their kids a favor by not being so overbearing, and allowed for much more independent development.

Bray is now doing post-doctoral research at the University of Arizona, where she is working with Canine Companions for Independence (CCI) to determine if maternal style has similar effects on the outcomes of dogs that will be trained to assist people with a wide range of disabilities. She is also now doing cognition and temperament tests on moms pre-pregnancy to determine if maternal behavior can be predicted before the dogs have puppies. Knowing this could be a game changer, as this information could be used for selective breeding of better moms.

Me snuggling Ashton, one of the Puppy Kindergarten dogs

If you got the chance to hang out with puppies Ashton, Aiden, or Dune last semester, you have an idea of how awesome Bray’s day-to-day work is. These pups were bred at CCI, and sent to Duke to be enrolled in Duke Puppy Kindergarten, a new program on campus run through Duke’s Canine Cognition Center. Which of these three will make it to graduation? I’ve got money on Ashton, but I guess we’ll have to wait and see.

The bottom line according to Bray? “Mothering matters, but in moderation.”

Overcoming Judgment Biases in STEM

Beginning in childhood we all develop unconscious stereotypes that influence how we see ourselves and others – including what careers we choose, and who we choose to recruit, hire or promote in the workplace.

Researchers discussed the origins and effects of these judgement biases during a virtual conference titled Mitigating Implicit Bias: Tools for the Neuroscientist, which was put on by the Society for Neuroscience and screened by DIBS at Duke on Jan. 23 and 24.

Associate professor of neuroscience Anne Churchland of Cold Spring Harbor Laboratory proposed several ideas for overcoming gender bias in the workplace, especially for women in STEM or other male-dominated domains. Asking questions, speaking with authority (particularly about one’s own work), finding a way to communicate with senior colleagues, trying risky experiments, making one’s achievements known, sending one’s work to high-level journals, and applying to awards and grants are her main suggestions. Above all these strategies, she recommends finding good friends and colleagues to help. As research shows, when women are successful in arenas that are viewed as distinctly male, both women and men like them less. These negative reactions can be discouraging and even career-affecting, and any support system will help to overcome that struggle.

The ‘Brilliance Barrier ‘ is a judgement bias explored by Andrei Cimpian’s research at New York University. One study shows that for every ten parents who searched on Google, “Is my daughter talented?”, twenty-five parents looked up “Is my son talented?”

Another study describes the gendered reviews on ratemyprofessor.com. Men are two to three times more likely to be called genius than women. Women though are more likely to be portrayed as warm or caring.

Cimpian uses these studies to develop the Field-specific Ability Beliefs hypothesis (FAB). FAB attributes women’s underrepresentation to a combination of the idolized brilliance/genius and the “brilliance” equals men stereotype. The higher the FAB in a field, the greater the emphasis on brilliance in it. When graphing the percentage of women with PhDs and the FAB for a specific field such as philosophy or physics, higher FABs are associated with a lower number of PhDs. African American representation also decreases as the FAB increases. Cimpian classifies one potential mechanism of this trend as minorities having less interest in fields with high FABs. In addition, increased bias, discrimination, and imposter syndrome could explain why minorities appear to avoid getting PhDs in high FAB fields.

Cimpian also demonstrates how susceptible children are to judgement biases. At age five, the percentage of girls who pick their own gender as “really, really smart” and the percentage of boys who do the same are similar. When children reach seven though, the percentage of boys choosing men exceeds the girls picking women. He suggests de-emphasizing brilliance, genius, and gifted in favor of work ethic because minorities are more likely to be recommended when the job description asks for commitment than when it asks for intelligence. Language has the potential to change the amount of representation in high FAB fields, such as STEM.

Image result for jackie fleming cartoons
Never Give Up – Cartoon by Jackie Fleming

Lastly, psychology professor Ione Fine at the University of Washington talked about the hiring process in her lab and how she reduces bias by laying out and weighting criteria beforehand. Instead of focusing on objective criteria like GPA and GRE scores, she advocates for more interviews with set lists of questions and a paper discussion. She also recommends calling the recommendation letter writers. After selecting a diverse group of research assistants, Fine then makes sure they have the proper support and mentoring. Reinforcing that they were chosen for their potential and that she is their advocate helps them feel empowered to succeed in her lab. Through mentoring and supporting diversity, anyone can help minorities overcome the judgement biases surrounding them.   

Nature vs. Nurture and Addiction

Epigenetics involves modifications to DNA that do not change its sequence but only affect which genes are active, or expressed. Photo courtesy of whatisepigenetics.com

The progressive understanding of addiction as a disease rather than a choice has opened the door to better treatment and research, but there are aspects of addiction that make it uniquely difficult to treat.

One exceptional characteristic of addiction is its persistence even in the absence of drug use: during periods of abstinence, symptoms get worse over time, and response to the drug increases.

Researcher Elizabeth Heller, PhD, of the University of Pennsylvania Epigenetics Institute, is interested in understanding why we observe this persistence in symptoms even after drug use, the initial cause of the addiction, is stopped. Heller, who spoke at a Jan. 18 biochemistry seminar, believes the answer lies in epigenetic regulation.

Elizabeth Heller is interested in how changes in gene expression can explain the chronic nature of addiction.

Epigenetic regulation represents the nurture part of “nature vs. nurture.” Without changing the actual sequence of DNA, we have mechanisms in our body to control how and when cells express certain genes. These mechanisms are influenced by changes in our environment, and the process of influencing gene expression without altering the basic genetic code is called epigenetics.

Heller believes that we can understand the persistent nature of the symptoms of drugs of abuse even during abstinence by considering epigenetic changes caused by the drugs themselves.

To investigate the role of epigenetics in addiction, specifically cocaine addiction, Heller and her team have developed a series of tools to bind to DNA and influence expression of the molecules that play a role in epigenetic regulation, which are called transcription factors. They identified the FosB gene, which has been previously implicated as a regulator of drug addiction, as a site for these changes.

Increased expression of the FosB gene has been shown to increase sensitivity to cocaine, meaning individuals expressing this gene respond more than those not expressing it. Heller found that cocaine users show decreased levels of the protein responsible for inhibiting expression of FosB. This suggests cocaine use itself is depleting the protein that could help regulate and attenuate response to cocaine, making it more addictive.

Another gene, Nr4a1, is important in dopamine signaling, the reward pathway that is “hijacked” by drugs of abuse.  This gene has been shown to attenuate reward response to cocaine in mice. Mice who underwent epigenetic changes to suppress Nr4a1 showed increased reward response to cocaine. A drug that is currently used in cancer treatment has been shown to suppress Nr4a1 and, consequently, Heller has shown it can reduce cocaine reward behavior in mice.

The identification of genes like FosB and Nr4a1 and evidence that changes in gene expression are even greater in periods of abstinence than during drug use. These may be exciting leaps in our understanding of addiction, and ultimately finding treatments best-suited to such a unique and devastating disease.   

Post by undergraduate blogger Sarah Haurin

Post by undergraduate blogger Sarah Haurin

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