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.
“Life is not simple,” Kulminski says. “We need to combine
“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
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.
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.
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.
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.
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.”
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.”
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.”
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.
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.”
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.
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.
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.
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.
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.
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
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.
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.
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?
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?
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.
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.
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.
At the intersection of social psychology, data science and fashion is Amy Winecoff.
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
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.
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.
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.
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.
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.
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.
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.”