from the world's big
What Rats Can Teach Us About Confidence
Dr. Adam Kepecs, Assistant Professor at Cold Spring Harbor Laboratory, studies the neural basis of decision-making. After receiving his B.Sc. degree in computer science and mathematics at Eotvos Lorand University, Hungary, he switched to studying the brain, completing his Ph.D. at Brandeis University in theoretical neuroscience. During his postdoctoral training at CSHL he began studying cognition in rats, discovering neural correlates of decision confidence. In 2009, Dr. Kepecs received the Klingenstein Fellowship in the Neurosciences and was named a Fellow of the Alfred P. Sloan Foundation. This year, he was selected as a John Merck Scholar. Since 2007, he has headed a research laboratory at CSHL where he employs sophisticated behavioral paradigms and electrophysiological, optical and molecular techniques to study the neural circuitry underlying decision-making in rodents.
Question: What do you study?
Adam Kepecs: So I study the neurology of decision making, how brains make decisions and one of my main interests is in trying to translate the folk psychological concepts like confidence into objects that we can study scientifically at a level of the brain and neuro circuits.
Question: How can confidence be measured scientifically?
Adam Kepecs: So let me tell you first a story, so imagine someone tells you about a new restaurant and you get the instructions and you start driving and you see the sign that tells you this is where you have to turn and you take the turn and you keep driving. You keep driving and there is no restaurant and you keep driving, no restaurant. At some point you’re going to turn around. When do you turn around? If you know your degree of confidence is kind of when you confidence level bottoms out is when you would take that u-turn and this is the kind of question that we try to translate into neuroscience, so of course these kind of questions have been of interest to a wide range of fields from economics to psychology, from medicine to computer science. What was unique about what we can do in our biology is really try to understand the mechanisms at the level of individual neurons, the nerve cells of the brain that are sort of the workhorses of the brain and understand how their connections, how their architecture and how the dynamics that runs on that architecture allows us or allows mammals in general to make decisions to compute confidence about decisions and so on.
Question: Why use rats rather than humans in your studies?
Adam Kepecs: So there are many reasons to use rats. So first of all, I should say that from an evolutionary perspective rats are not that different from us and some of the fundamental brain architecture is really common and that really allows us to tap into a system that is simpler and that is a great advantage and in that sense I think one of the perhaps underappreciated aspects of studying a simpler system is imagine if you were wanting to understand how a car works. You might want to start with the latest Lexus, but then perhaps you get lost in all the latest gadgets, the stereo, the GPS, the air conditioning system, the motorized car seats and you forget about the fundamentals. Perhaps it would be better to start with the Ford Model T. That is a very simple car, but it has all the components that make it a car. In some ways we feel that rodents have all the components that make them function, that make them able to decide and it’s going to be easier for us to understand. Now of course by using rodents we can also tap into an enormous field of technologies that really allow us to get mechanistic, not just observe in general what a brain region is doing, but observe at the level of individual neurons and finally to actually understand how different neurons come together in circuits and then manipulate these and really understand the causal substrate of decisions and that’s really one of the things we’re excited about that we can do this now.
So what we do is train rats to make simple two alternative choices between a left and a right port and you can see in the center the animal gets an order and then we train them so that they respond to the left reward port for order A and the right reward port for order B and as you can see they can do this really fast. We can get hundreds and hundreds of trials. They are really good at it and in fact, one of the problems that we faced was that they’re so good at it they almost don’t ever make mistakes with any two orders, so what we do to make them uncertain is to mix the two orders and then we ask them to decide rather a particular mixture is more like mixture A or more like order A or more like order B and that is the fundamental task that we study.
Question: How does confidence play into that?
Adam Kepecs: Okay, so this is interesting. So now we can translate our story about going to this restaurant and trying to turn around into a rat ****, so imagine the same scenario where the animals make going back and forth between a stimulus and a response, but we delay the reward. It’s a little bit like the restaurant that may or may not appear on the road and we can ask how long is an animal willing to wait for the reward. Then what we can do is we can make the stimulus more difficult. We can dial in the difficulty based on the mixture ratio and that is a little bit like changing your memory of the instructions of how to get to restaurant or changing how foggy the day is and whether how well you can see the sign, so we can vary those things and then measure how long an animal is willing to wait for the reward and again do this hundreds and hundreds of times a day, which really allows them first of all to calibrate their confidence in these simple decisions and it also allow us from a neurobiological perspective to actually look into their brain and what happens in their brains when they’re doing this task.
Kepecs uses rats to study the neurology of decision-making because their brains are evolutionarily similar to ours but much simpler. Likewise, if you wanted to learn how cars worked, you wouldn’t study a complicated Lexus; you’d study a Model T.
Join The Daily Show comedian Jordan Klepper and elite improviser Bob Kulhan live at 1 pm ET on Tuesday, July 14!
Gender and sexual minority populations are experiencing rising anxiety and depression rates during the pandemic.
- Anxiety and depression rates are spiking in the LGBTQ+ community, and especially in individuals who hadn't struggled with those issues in the past.
- Overall, depression increased by an average PHQ-9 score of 1.21 and anxiety increased by an average GAD-7 score of 3.11.
- The researchers recommended that health care providers check in with LGBTQ+ patients about stress and screen for mood and anxiety disorders—even among those with no prior history of anxiety or depression.
Study findings<p>For the study, <a href="https://link.springer.com/article/10.1007/s11606-020-05970-4" target="_blank">published in the Journal of General Internal Medicine</a><em>, </em>Flentje and her team evaluated survey responses from nearly 2,300 individuals who identified as being in the lesbian, gay, bisexual, transgender, and queer (LGBTQ+) community. Most of the participants were white, while nearly 19 percent identified as a racial or ethnic minority. Multiple genders were represented with cisgender women (27.2 percent) and men (24.6 percent) making up a majority of the participants. Sixty-three percent had been assigned female at birth. For the most part, participants identified their sexual orientations as queer (40.3 percent), gay (36.5 percent), and bisexual (30.3 percent).</p><p>The JGIM study participants were recruited from the 18,000-participant <a href="https://pridestudy.org/" target="_blank">PRIDE Study</a> (Population Research in Identity and Disparities for Equality), which is the first large-scale, long-term national study focusing on American adults who identify as LGBTQ+. It conducts annual questionnaires to understand factors related to health and disease in this population. </p><p>Participants filled out an annual questionnaire (starting in June 2019) and a COVID-19 impact survey this past spring. Flentje noted that on an individual level, some people may not have experienced a big change in anxiety or depression levels, but for others there was. Overall, depression increased by a <a href="https://patient.info/doctor/patient-health-questionnaire-phq-9" target="_blank">PHQ-9 score</a> of 1.21, putting it at 8.31 on average. Anxiety went up by a <a href="https://www.mdcalc.com/gad-7-general-anxiety-disorder-7" target="_blank">GAD-7</a> score of 3.11 to an average of 8.89. Interestingly, the average PHQ-9 scores for those who screened positive for depression at the first 2019 survey decreased by 1.08. Those who screened negative for depression saw their PHQ-9 scores increase by 2.17 on average. As for anxiety, researchers detected no GAD-7 change among the study participants who screened positive for anxiety in the first survey, but did see an overall increase of 3.93 among those who had initially been evaluated as negative for the disorder. </p>
Risks among gender and sexual minorities<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="fc3fd1ae68b77bbbf58a6995638d6d65"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/EnUqDjCqg0A?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>The LGBTQ+ community is a vulnerable population to mental health concerns because of their fear of stigmatization and previous discriminatory experiences.</p> <p>Previous research by the Human Rights Campaign has found "that LGBTQ Americans are more likely than the <a href="https://medicalxpress.com/tags/general+population/" target="_blank">general population</a> to live in poverty and lack access to adequate medical care, paid <a href="https://medicalxpress.com/tags/medical+leave/" target="_blank">medical leave</a>, and basic necessities during the pandemic," said researcher Tari Hanneman, director of the health and aging program at the campaign.</p> <p>"Therefore, it is not surprising to see this increase in anxiety and depression among this population," Hanneman said in the release. "This study highlights the need for <a href="https://medicalxpress.com/tags/health+care+professionals/" target="_blank">health care professionals</a> to support, affirm and provide <a href="https://medicalxpress.com/tags/critical+care/" target="_blank">critical care</a> for the LGBTQ community to manage and maintain their mental health, as well as their physical health, during this pandemic."</p>
What should health care providers do?<p>The authors of the study recommend that health care providers check in with LGBTQ+ patients about stress and screen for mood and anxiety disorders in members of that community—even among those with no prior history of anxiety or depression.</p><p>As cases of COVID-19 continue to mount, the sustained social distancing, potential isolation, economic precariousness, and personal illness, grief, and loss are bound to have increased and varied impacts on mental health. Effective treatments may include individual therapy and medications as well as more large-scale coronavirus support programs like peer-led groups and mindfulness practices. </p><p>"It will be important to find out what happens over time and to identify who is most at risk, so we can be sure to roll out public health interventions to support the mental health of our communities in the best and most effective ways," said Flentje.</p>
What we know about black holes is both fascinating and scary.
- When it comes to black holes, science simultaneously knows so much and so little, which is why they are so fascinating. Focusing on what we do know, this group of astronomers, educators, and physicists share some of the most incredible facts about the powerful and mysterious objects.
- A black hole is so massive that light (and anything else it swallows) can't escape, says Bill Nye. You can't see a black hole, theoretical physicists Michio Kaku and Christophe Galfard explain, because it is too dark. What you can see, however, is the distortion of light around it caused by its extreme gravity.
- Explaining one unsettling concept from astrophysics called spaghettification, astronomer Michelle Thaller says that "If you got close to a black hole there would be tides over your body that small that would rip you apart into basically a strand of spaghetti that would fall down the black hole."
The team caught a glimpse of a process that takes 18,000,000,000,000,000,000,000 years.
- In Italy, a team of scientists is using a highly sophisticated detector to hunt for dark matter.
- The team observed an ultra-rare particle interaction that reveals the half-life of a xenon-124 atom to be 18 sextillion years.
- The half-life of a process is how long it takes for half of the radioactive nuclei present in a sample to decay.
A new study looks at what would happen to human language on a long journey to other star systems.
- A new study proposes that language could change dramatically on long space voyages.
- Spacefaring people might lose the ability to understand the people of Earth.
- This scenario is of particular concern for potential "generation ships".