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Welcome to the podcast, everyone. We are here again with a clinical episode. This time, my guest is a true legend in our field.
For more than 50 years, Dr. Michael (Mike) Posner has studied how mental operations, particularly those related to attention, are carried out by neural networks. He has used cognitive, imaging, and genetic methods in his studies. In 1998, he was founding director of the Sackler Institute at Weill Medical College. He continues his research as Prof. Emeritus of Psychology at the University of Oregon and Adjunct Prof. at Weill Medical College. He has received many honors including being elected to NAS 1981, 2009 the medal of science presented by President Obama, maybe you’ve heard of him, and in 2017 he was awarded the Franklin Medal in Computer and Cognitive Science.
Mike has been in the field for over 50 years. He is a prolific researcher. He has been cited nearly 170,000 times on Google Scholar. His work spans decades, quite simply.
So this is a really engaging and intriguing conversation for me. I started out and approached this interview thinking we may just talk about attention, his theory of attention, and newer research with attention and memory, but our conversation delved into many aspects of Mike’s career and what it’s like to have been in the field for so long to see so many changes in the field, the evolution of the field. It was just a delightful conversation all around.
Without further ado, I will give you my conversation with Dr. Mike Posner.
Hey, Mike, welcome to the podcast.
Dr. Posner: Well, thank you very much for having me.
Dr. Sharp: Absolutely. I am honored to have you here. You have been doing this work for a long time. I think a lot of people know your name. So I just appreciate that you’re willing to take the time to chat with me here for a little bit.
I was looking on preparing for our interview and typically I’ll go through and try to read some of them folks’ work and get a handle on their research and so forth, but I quickly figured out that that would be a very, very challenging thing to do for you because you’ve been cited in Google Scholar more than anyone I’ve ever seen. You’ve been quite a prolific researcher over the years. That’s impressive.
So, I wanted to start maybe with a question related to that. You’ve dedicated a lot of time and energy to researching attention. So, why this? I mean, out of everything in psychology, why spend your time on attention?
Dr. Posner: I really wanted to know how the brain works. It seemed to me that being aware of things around you, visual things in the case of scanning the world or auditory things, indeed the idea is inside. And the interface between our awareness of the world around us seemed to be the study of attention. I thought this might be an entry. Actually, my wife told me that when I was courting her, she asked me what I planned to do with my life, I said, “I’m hoping to figure out how the brain works.” It was successful. She married me anyway. So I followed out on it.
Dr. Sharp: In spite of that, she married you. That’s great.
My understanding anyway is that our field’s understanding of attention has really evolved over the years. And even some of your research has evolved. I wonder if you might be willing to walk us through just a brief history of attention. I know that might be tough but I wonder if we might take a stab at that?
Dr. Posner: I won’t walk you through the 4 volumes that I wrote on the history of attention. Actually, I didn’t write but edited. It goes back 2500 years ago. People wondered how they could control their minds and has a long tradition in philosophy and so on. Its scientific tradition is shorter, but certainly, it goes back to the late 1800s. And even during the time when psychology was mainly about behavior with the theory of behaviorism, some of the main methods for studying attention were being developed.
Most people start the history at the end of World War II where particularly in order to try to understand how people could stay awake over long periods of time and pay attention to tasks, particularly in England but also in the United States, people began to study attention as an empirical discipline to try to understand how they could influence it.
And of course, in the late 1900s, with the development of brain imaging, it became possible to ask what are the mechanisms in the brain allow us to pay attention. And that really, I think, transformed the field from one largely based on experimental psychology to one based partly on imaging and partly on animal models and theories of artificial intelligence and so on that came through many disciplines.
Dr. Sharp: Right. I know you’ve done a lot of work with brain imaging. I want to certainly dive into that as we go along. And forgive me for not knowing this, but when you started researching attention, was brain imaging anywhere on the radar, or did that come along later in your career?
Dr. Posner: Well, hemodynamic brain imaging, what most people call brain imaging, really didn’t begin until the 1970s when the Scandinavians, Ingvar, and others, began to use inhaled Xenon to image activity in the brain.
My involvement with it began in the mid-1980s when I traveled from Oregon, which was my home base, to St. Louis to work with Marcus Raichle and the people at Washington University (WashU) medical school doing positron emission tomography. Raichle had developed a short-lived isotope of oxygen, O-15, and was able to really look at cognitive tasks in a way which the Scandinavians hadn’t yet been successful at. They had looked at like paying attention to a musical piece and, or reading aloud and showed much of the brain and different parts of the brain, but much of the brain we’re active in all these tasks, but they hadn’t really taken a cognitive approach to measure mental operations, which has been the heart of cognitive psychology.
Marcus Raichle and I took the ideas about mental operations and designed tasks that would allow us to isolate, not just say the brain is active in many places when you read, but isolate the phonological, visual, and semantic codes involved in the reading task.
That really transformed the field in ways that I couldn’t have imagined at the time because we had the idea that these tasks weren’t in one place in the brain, but even it’s very simple, psychological tasks involve a set of small isolated areas that had to be brought together orchestrated in a way which allowed you to carry out the task. And that is the underlying idea with brain networks, which right at this moment of time is probably the dominant idea in the field.
Dr. Sharp: Right. It’s so fascinating to me. Can you think back to that time, and do you remember the energy or the emotion around this kind of research? Did you know back then, or were you aware, like we’re doing something really cool?
Dr. Posner: I was perfectly aware of the highly emotional atmosphere in which we did this. For one thing, almost all my contemporary psychologists thought it was a fool’s errand. It may sound strange, but the reason being, in cognitive psychology, the mantra was it’s all about software. It really doesn’t matter the hardware that you use to run that software. Part of it came from computer simulation because, of course, you use various, I used IBMs, you use Macs, you might’ve used different computers, but people just didn’t think that understanding the underlying physiology really made any difference for cognitive psychology.
I did and shared that view. Of course, I didn’t know that this would take over the field in such a dramatic way. I just thought maybe we could make a connection and I could test a theory that I had about brain networks that came out of my work with patients with specific lesions in the brain. I was able to test the theory. I thought it was correct. It’s, of course, been changed a lot by many subsequent events. I think I did have ideas that were a strong contributor to what we’ve eventually found out.
Dr. Sharp: Absolutely. That might be a nice way to provide a little bit of a framework for our conversation. Would you be able to outline just your work over the years and how your research has evolved or changed in the different areas or types of work you have done over the past few decades?
Dr. Posner: Well, that may be a tease for something I wanted to tell you. I’ve just written a memoir of my over 60 years in psychology. I have a complete electronic form, but it will be printed. I’m self-publishing it. I knew my daughters-in-law were both interested in it, but I didn’t think probably many other people would be, but I suppose by the 1st of the year, it will be available from many different publishing sources. It’s called Overskirts Press. It’s as I said, a self-published volume, but I did have some meritorious work. I think I’m mostly going to have the final proofing to do.
Having written that, of course, I haven’t answered your question, it’s a little long to go into. I can say that there have been dramatic changes in the field. I’ve been called by many names during the time that I’ve worked in psychology. When I began, people who took the approach that I took, that is careful measurements of mental operations during tasks like matching two letters to say whether they had the same name or not, that kind of approach was called experimental psychology, but experimental psychology also includes a lot of animal work from rats and so on.
And when Neisser, in 1968 wrote the book, Cognitive Psychology textbook, then the name became cognitive psychology. I used that name as, of course, many others. And then when imaging came along, it got to be a part of not only psychology but neuroscience and we were called cognitive neuroscientists or sometimes systems neuroscientists, mostly for me, a cognitive neuroscientist. So, it was yet another name.
So, those presage methodological differences take place because new methods become available. I did use a method of imaging the brain prior to hemodynamic imaging. Prior to the 80s, many people used electrical recordings from the scalp so-called EEG recordings. And we averaged over many trials to produce a picture of the Timelock brain activity that would go on overtime.
There were a lot of suspicions about electrical recording from as far away as the scalp. It was a long way from the neurons which were actually producing the signal, but in retrospect, once hemodynamic imaging told you that there were particular areas of the brain that were generating it, then you could use electrical imaging in a more convincing way, because it’s difficult from a distribution of scalp electrical activity, in fact, impossible, to localize the generator, but if you start off with the generator, you can predict the scalp electrical activity.
And so in the current scene, electrical recording has quite a bit of legitimacy, both electrical and magnetic recording from on the skull or outside of the skull. And when I started doing it and many others, although we were convinced we were learning things about the brain, a lot of people doubted it.
Dr. Sharp: I can imagine. I’m just curious, we will get into attention and the specific work that you’ve done, but I am just curious about this experience of advancing theories or ideas that others did not agree with because I think we all wrestle with this in some form or fashion. How do you stand up in the face of disagreement and know that you’re doing the right thing? Was there some doubt? How did you work through that?
Dr. Posner: Well, there was always doubt. Even in retrospect, there’s doubt whether you’ve done the right thing. I never participated much in disputations about it. I just thought I would proceed as best I could with my limited abilities. I do the best I can and hopefully, I would learn something that would satisfy me and maybe others would feel that it was useful too. You never know.
When I got into imaging, most of my contemporaries in psychology thought it was just a ridiculous thing to do, but other fields were very interested in it. For example, the very famous physicists of Baylor OALA also wanted to measure brain activity using positron emission tomography. He and I both wanted to get on the machine. And there was a lot of contra competition among people in different fields. In psychology, there wasn’t much competition because as I said, people didn’t think it would work. And I had obviously considerable doubts whether it would work or not but I felt that devoting a few years to trying would be worthwhile.
Dr. Sharp: That’s a good way to put it. We talk about imposter syndrome a lot in our field and with our work. Well, does that ever go away? Do you ever lose that sense of imposter syndrome at some point?
Dr. Posner: You always feel you’re inadequate to the questions you’re asking. Of course, I didn’t think I was telling my wife quite the truth when I said I wanted to figure out how the brain works. It was a desire. I didn’t expect to actually do it, but it did help keep my motivation up. And she joined me in being very enthusiastic about it.
Dr. Sharp: Certainly worked out as far as I can tell. It seems like you had a pretty big contribution to our field. I would love to dig into some of that and talk about the nuances of attention. This has been your area for a long time. I hate to trouble you with a basic question, but I know folks are out there who could benefit from hearing a good working definition of attention. I wonder if we could just start there. What are we talking about when you say attention? What are we even looking at?
Dr. Posner: I’m really talking about nowadays three brain networks, which were partly defined even before there was imaging. One of them is getting and maintaining the alert state.
Everyone knows what it is to be alert and everyone knows what it is to fail to be alert. You can say, well, how do you go from a state where you’re resting to one where you’re alert and involved as I am in your question? That’s called the alerting network. We know a lot about it. It primarily uses the brain’s neuromodulator norepinephrine rising in the brain stem, in the locus coeruleus, and interacting with much of the dorsal cortex. It can change you from a resting state to a state of highly engagement, getting ready for the task. And then when the task occurs, responding. And so alerting is one aspect of it.
Another one is what I call orienting. You and I can see each other. I know your listeners can only hear, so they’re oriented to the auditory modality. They’re listening to my words or your words. Sometimes, we switched to a visual. If a person comes in the door that you weren’t expecting, you orient, turn to him or draw attention to him.
So orienting is surprisingly common. There’s a common orienting system, even though it might be to different modalities like vision or audition or smell or whatever, and allows you to give priority to the sensory information that’s coming in on the modality or set of modalities that you’ve chosen to orient or have been forced by some out external event.
And then there’s what I call the executive network. It’s called, in imaging, the cingulo-opercular network. They normally, in imaging, call things by their anatomy, but I usually use its function. And this controls what you might call your evolutionary behavior, including what we would call focal attention.
So if I am really engaged in looking at you and attending to you carefully, things can happen in the periphery. And if they don’t have any motion or luminance changed, I might not even notice them. Even if some crazy thing happened, like a horse’s head occurred somehow outside, I would maybe not notice it.
And there have been experiments that show when you suppress the particular cues for orienting, which are heavily motion and ruminations chain, then something can occur as even that’s very compelling such as a new figure or, as I said, a horse’s head, you don’t notice it. It doesn’t come to attention.
So that kind of attention is what I call executive attention. I believe, and this is not shared by everyone, I believe it’s the key to understanding what we’re conscious of. And that’s obviously an important question by itself, but that’s what the executive. Certainly, it’s involved in all kinds of evolutionary movements and choices, including the control of what you’re going to bring to consciousness.
Dr. Sharp: Yeah. It makes me think of that video that went around, I don’t even know how many years ago, but it’s the video of the basketball players on the court and the intro says, count the number of passes that these basketball players make. And then you’re busy counting the passes. And then after the video, they reveal that a guy in a gorilla suit walked across the court, and did you see it? Whatever percentage of people say, well, no, I didn’t. I think we’re in the same ballpark, right?
Dr. Posner: That’s the work of Rensink and others. And it’s called attentional blindness that you’re kind of blind to things outside the focal attention. It’s not always true though, because if you’re not focally engaged, then your attention can be drawn to almost anything without much problem.
I mean, there’s not much cause of having to orient to something if you’re not already very seriously engaged in what you’re attending to in the executive sense, but each of these senses of attention has its own brain network. And to me, that’s come to be a strong definition. It may not include all the important aspects of attention. There may be other networks that I’m not aware of or less aware of than these three, but it gives us an idea of the scope of the field.
Most laypeople don’t really understand that we actually do know the brain mechanisms of a lot of aspects of attention. Maybe not fully, maybe not for all time, there may be new findings or will be new findings and new methods for exploring it, just like optical telescopes are not replaced by radio telescopes, but radio telehealth opened up a whole new window and hopefully, we’ll have whole new windows in the future.
Dr. Sharp: Right. I have so many questions about that. The quote that I wrote down, you said that the executive network is the key to understanding what we’re conscious of. Is that how you phrased it?
Dr. Posner: That’s how I should phrase it. Yes.
Dr. Sharp: Can you say more about that? What do you mean by that?
Dr. Posner: Well, it’s been shown that when you’re conscious of something, there’s a whole aspect, a very large part of the brain becomes synchronized with that object. And it’s often called an attentional workspace from the work of Berenstain Bears and Stan Dohan. And I agree with that. That happens, but I think it has to have a starting point. And the starting point, I think, I’ve never really been able to prove to everyone’s satisfaction, maybe not even on my own, but I think it is this executive network that it starts it. It has a particular type of cell which has very long axonal connections to other parts of the brain. It brings in other parts of the brain and forms a strong, almost full brain, not quite the whole brain, but almost full brain synchrony around the attentional object if you continue attending to it for a long time.
Dr. Sharp: Yes. Describing these networks, there has to be some interplay between them. Am I right there?
Dr. Posner: They’re definitely not if they’re in separate brains. They’re all in the same brain. They communicate. Just like almost every scientific problem, in the real world, it’s a whole network. You can talk about all the different activities. And, of course, the scientist’s goal is to break it down into the critical components so that they can really investigate them and understand them. That’s what we’ve done in trying to look at attention. There’s controversy about all the networks, but I think it’s progress to have these brain networks as a kind of a basic idea of what a scientific aspect of attention would be.
Dr. Sharp: Yes. I’m going to ask a question that may fall outside the scope of your knowledge. If that is true, that’s totally okay, but I want to take a stab at it. Can you talk about the relationship of these networks and attention to maybe like the neuro-psychological construct of executive functioning and even like a diagnosis of ADHD? Have you looked at that kind of thing much at all?
Dr. Posner: In conjunction with my friend, Jim Swanson, who’s probably the world’s expert on Attention Deficit Disorder, I have looked at aspects of it. I’m not sure we’ve solved all the questions of `attention deficit disorder. Jim has provided strong diagnostic tools for it.
He developed a school at one time. While he was involved with it, it was really the very best place to treat people who had this disorder. He even developed a new treatment based upon the finding that methylphenidate as a drug improves people’s ability to maintain focused attention and so on. For children who were diagnosed with attention deficit disorder, he developed a once-a-day pill. Because the methylphenidate quickly adapted, you’d have to take it every few hours, very bad for children to have to leave school and take medication. That was not good. So he developed a once-a-day pill, Concerta, which took over the drug market for this.
But also to his credit, he also found flaws with this treatment. For one thing, he believes that if you take it for a very long period of time, it might limit the height at which children grow. And so that makes a trade-off. It does have good effects on their focusing and their success in school and so on, but there are also some side effects that maybe wouldn’t be very desirable.
Dr. Sharp: Right. Now, my understanding with our conceptualization of attention is that over the years, it seems like the work has moved more in the direction of the integration of say genes and environment and culture and parenting and so forth. I’m curious to get your thoughts on that if we might dig into that a little bit.
Dr. Posner: Well, I believe that attention deficit or a very common aspect of mentee mental disorders. That doesn’t mean that attention solves all mental disorders. It doesn’t. But it does give you a clue.
I have written papers in which I try to divide different definitions or psychopathologies or whatever you want to call these disorders, and try to divide them based on what attention network is most affected in that disorder. And my idea isn’t that that would necessarily solve the problem of how to treat the disorder, but it would give someone who’s a scholar of that disorder, a start in seeing how that might aluminate a particular treatment.
Depression has been one that’s been very frequently called attention disorder. A strong concentration on negative effects and an inability to break off from negative effects. Some of the treatments for depression, the psychological treatments for depression build on this.
Interestingly enough, it’s been shown that the psychological treatment called cognitive behavioral therapy, which is very common to be used here, and the drug treatments affect completely different aspects of the disorder. You can see this in imaging and that has been studied a lot. It’s kind of a better paradigm case for how much you can learn about different treatments by looking at the images of that treatment. What parts of the brain are affected by that treatment?
Helen Mayberg has published a lot on this and illuminated depression, its drug treatment, and cognitive-behavioral treatment which both are effective to some extent, but not completely effective. And she’s illuminated that whole topic
Dr. Sharp: And just for listeners, all the resources and people that we mentioned will be in the show notes as usual. You’re giving me some homework to do.
Dr. Posner: Oh, sorry. I’ve spent most of my life as a teacher.
Dr. Sharp: Oh, that’s great. I’ll take it.
Dr. Posner: I am usually not limited to the work that I’ve done, but to the work that’s going on in the field. At one time, I used to be very good at this but these days, since I haven’t really taught psychology for over 20 years, I’m not quite as sharp as I used to be.
Dr. Sharp: Well, you’re still giving me plenty to look at, so it doesn’t seem like you’ve lost it quite yet. I wanted to go back and ask about a couple of things that you said. One, just to clarify, did you say, and I may have gotten this wrong, that the brain networks that are lighting up on imaging are different for CBT versus a pharmacological treatment?
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Dr. Posner: For cognitive-behavioral therapy, yes, I did say that. Actually, Helen Mayberg said it and I was quoting from her work. She’s a psychiatrist. She has done treatment in this area. She’s now at Emory University in Georgia, I believe, at least last I heard.
Dr. Sharp: Got you. Yeah, that in itself is interesting to me. This point that you bring up of attention playing a pretty major role in these different disorders. We’ve done a lot of talks here on the podcast about dimensional models of diagnosis versus categorical. It just makes me think about that and how attention is a common factor across the board for a lot of diagnoses that we have, but not included in the diagnostic criteria, of course, for depression necessarily.
So, I wanted to ask about other instances of attention. As far as you have written about or thought about, where else do you see attention playing a major role in mental health that may not be obvious? ADHD is obvious, but depression…
Dr. Posner: Autism is one place where it’s been reported. Usually, people think of it as a social disorder and a failure to orient to social events, but early on before it usually is diagnosed, there’s a general orienting deficit in autism.
Several people have written about it. Jean Townsend is one of the people who’ve written the most about this. And that could be or may be not a clue to how one might intervene at an earlier time even before the social disorder has become apparent, which isn’t usually until two years of life.
Dr. Sharp: That’s a great example. I didn’t want to cut you off. Were there other examples that you wanted to mention? If not, that’s okay.
Dr. Posner: Well, neurologic, the way I got into this way of thinking about it before imaging was because people began to look at the parietal lobes as an area where there were cells and neurons that were related to attention.
Vernon Mountcastle, a very well-known neurophysiologist, wrote a paper in the late 70s on this. And I got very interested in this because I thought it might be possible to relate the psychological phenomena that we were studying and orienting to these cells that Mountcastle was studying in the parietal lobe. And the key to it would be patients who had lesions of the parietal lobe. And so, with the help of a very well-known neurologist at the time, Oscar Morin, I set up a laboratory in Portland and we tested patients with lesions of the parietal lobe, who will be said by neurologists to have neglected of the side of space opposite the lesion as if that information didn’t get in.
And we found rather surprisingly that lesions of the parietal lobe were the only thing that produced a temporary and neglect. They produced the most profound neglect, but frontal lesions and lesions of the superior colliculus also produced a kind of neglect. And in fact, we had thought we had discovered a network of brain areas that produced a profound inability to orient attention in the opposite direction of the lesion, away from the area of current focus. And so we ran tests on patients with lesions in various places. And although all of these patients had a sort of neglect, the underlying mental operations that were involved seem to depend on the particular area of the brain which was activated, which we were studying, where had the lesions.
And that was the origin of my interest in network theory. But psychologists generally, although they pay some attention to the lesion patients and particularly those psychologists who are providing clinical services, of course, psychology is about a quarter of normal brain activity. And so many people would say, well, if they have a lesion of the brain, it’s going to be entirely different. You’re not going to get any insight into the normal person.
So I was looking for a method that might give us that insight. This was 1984 or so, and there was an advertisement from Washington University in St. Louis for psychologists who might work in conjunction with pet scanning. I had already read the Scandinavian papers. So I knew it was possible to look at the areas of the brain. And that’s how I went from the work on neuro-psychology patients to see if I could test my theory with mammals. That’s how I happened to go to St. Louis or as people said the wrong way on the Oregon Trail.
Dr. Sharp: I guess that’s true. Your work has evolved over the years, right? And I want to make sure and talk about some of the current work that you’re doing around attention and memory. Is that right?
Dr. Posner: That’s correct. It arose in a very strange way. I’ll tell you the story and then you can see why it happened to be this late in life working with mice having never done animal work before my graduate school days.
I worked with a man by the name of Yi-Yuan who had developed a method of meditation, which he called Integrative body-mind training. The unique part of his story was that he felt that within five days he could get profound effects in people. Only five days of training. Well, most of the work on meditation was comparing Buddhist monks who spent thousands and thousands of hours in meditation with a control group. How you get a control group for a Buddhist monk is very, very difficult to imagine.
And so it was very easy to set aside this research, but for five days, you could select a group of undergraduates and randomly assign them to either this meditation technique or we use relaxation training because it’s also a part of cognitive-behavioral therapy, very popular. And we found within five days, we were able to objectively measure changes in the executive network as measured by attention tasks and also changes in cortisol- the ability to the stress hormone and so on. So we had some pretty good effects after five days of training.
After 2 to 4 weeks of training, a really curious then was by using a so-called diffusion tensor imaging, which is a kind of magnetic resonance imaging that looks at white matter, we looked at a statistic called fractional anisotropy which is thought to be related to the efficiency of conducting over that white matter. And it improved after two weeks to a month of meditation training. We published two papers on this and there was very great skepticism.
For me, the big motivator was even my brother who’s helped my career all his life, who’s a very well-known neurologist, much better than I am. Now, maybe you’re wrong on this. And that was a strong motivator. And the key was to try to find what the effective ingredient of meditation is. That’s could be a lifetime job, but I went read the literature and I got the idea that the white matter change might be related to the strong frontal theta rhythm that is set up when you train to do meditation, even your resting state, even when you’re resting, following the meditation training, you get this strong frontal theta, 6-Hz rhythm in the electrical activity.
So I gave a talk on this and a young man came up to me afterward, an assistant professor at Oregon, now a very close friend of mine, Chris Neil. And he said, you know, we could test your theory in mice. His specialty was optogenetics and it was possible for him to get mice where you could impose by laser light in implanted lasers, not from the scalp, but implanted. You could impose a theta rhythm and ask yourself, did the white matter change?
His wife was able to do electron microscopy and show I think completely convincingly, at least to me, that we were able to get changes. The behavior of the mouse didn’t seem to change while we were stimulating him with theta rhythm, but afterward, we showed that after the white matter changed, they also showed reduced fear in fearful situations. There were behavioral changes as well. You also get reports from patients or from normal people who undergo meditation training that have reduced anxiety and fear.
So that was all very encouraging and got us into mice work. I’ve been following up with various studies in mice since that time. And one of the things that we’ve done is try to study the integration between attention networks, particularly the anterior single and this executive network, and learning a new skill. Now, mice are kind of hard to learn, but we have a mouse whisper in our group who’s very good with mice.
We’ve learned a lot about these two networks, one of them involving the ACC and, of course, other brain structures as well, and the other one, the memory network involving the hippocampus. And there are two dominant pathways between the two and we’re working on the whole question of what are their functions in normal learning. And we have considerable evidence from humans that they don’t differ that much from the mice in a lot of their learning at this level of learning basic associations. So, yeah, I’m working with mice trying to understand learning as an integration of two major brain networks that have been studied a great deal.
Dr. Sharp: Now, I’m guessing that people out there might be thinking, sure, it seems like attention and memory would be related. That seems to make sense. I wonder, and this is just not being as familiar with the literature, I just wonder how we’ve kind of gone this long without more of a clear understanding of this.
Dr. Posner: That’s not so surprising. Many people have written about how attention is related to memory. At the psychological level, that would be very common and unsurprising to people. Nonetheless, when Michael Merzenich showed that by attending to a task involving, this is a monkey, so the finger is called a digit, if you gave him a task on a particular digit and they attended closely to it, you would change the representation of that digit and the primary somatosensory cortex. And that was very surprising to neuroscientists when Michael Merzenich showed this.
So yes, on one level you can say, oh yeah, sure, obvious attention is related to memory. I agree with that. But the results that Michael Merzenich showed that really transformed a lot of the beliefs of neuroscientists about whether the nervous system could change with experience, which of course it can, but neuroscientists were a little doubtful until Merzenich was able to show it right at the primary somatosensory area. Then they generally had to accept this kind of plasticity.
So, once you have a question that you think is fundamental and there is learning that may be unconscious and not involve attention as much, but most of our learning, we all know involves careful attention. If I remember your name it is because I attended to it. I said, oh, I should call him Jeremy. But being able to look at the networks, the pathways and the direction of information flow, and so on all of which we’re doing right now, well, I hope what we’re doing right now is worth doing, I think.
Dr. Sharp: Absolutely. Sorry, I did not mean to imply it’s not worth doing by any means.
Dr. Posner: Yeah, I wasn’t saying that that was what you were saying, but you were asking me about, well, how come the people didn’t write about this over the years? Well, they did. There was a lot of writing about it and yet a discovery like Merzenich’s can really transform the field quite a bit.
Dr. Sharp: Yeah. And what about your findings thus far? Is there anything you can speak to even in terms of preliminary outcomes or in anything that you’re finding that is worth sharing?
Dr. Posner: The biggest surprise for me, I thought this would all be the executive network. The executive network was working with the hippocampus to store and retrieve information, but actually, the orienting network also works with the hippocampus.
A friend of mine, Michael Anderson developed a task in which people were asked what they learned. They learned a bunch of associations that could be words or pictures or picture-word or anything like that. And on some trials, they’d get a green light and they were supposed to think about that association. So you’d present them with a stimulus, whether a picture or word, and they were supposed to think about the response, what they had learned, but if it got a red light, they were supposed to avoid thinking about it.
Now, it’s true that the anterior cingulate and surrounding areas damp down the activity in the hippocampus when you’re at the red light. So that’s a relation between the executive network and hippocampus and memory. But if the person reports to you that he didn’t want to think about it, but he yet actually think about it all at that trial, it gives an honest report of failure to keep it out of mind. Then you see this other network which goes up to the parietal lobe, overlaps the orienting network pretty strongly active in imaging. So, we learned that there were actually two networks that were very important in aspects of learning new associations or at least aspects of it.
The interesting part about us, once you know that, then it helps explain in rats and other rodents, the dominant role of the hippocampus is not really memory it’s navigation. And it looks like the link between navigation in the rodent is that that involves an orienting network and that remains present, but the rodents mostly navigate, but humans, they spend time navigating, but they do a lot of other things.
And in the Anderson work that I described, it doesn’t matter what the content is. It doesn’t have to be spatial content. The spatial network is involved mainly because probably it had an old evolutionary development. And I thought it was interesting that this occurred and we found out something that was really wouldn’t have thought about, at least I wouldn’t have thought about before, and that may help us understand the whole evolutionary process by which this network evolves. That would be a good outcome, I think.
Dr. Sharp: Absolutely. Yes. Hearing you talk about it, I’m actually surprised as a completely naive individual in this whole equation that the alerting network is not more involved in this whole process. It seems like that would be a bedrock.
Dr. Posner: In the real world, that clearly has to be. We haven’t got a model task that shows that, but we probably could develop one. In the real world, of course, the full aspect of that executive performance depends big on the alert state. So getting into the alert state activates the anterior cingulate, for example. Before that, when you’re in what Mark Rico calls the default mode, you’re kind of relaxed and maybe ruminating about something like, how is this interview going, something like that and then you come out of it to pay attention to a question and everything, then you get into a state where the cingulate is very active and also the rest of the executive network.
Dr. Sharp: Got you. Well, I wonder where you see things headed from here. I know this research on memory is exciting, but I’m curious both for yourself and for the field in general, what’s coming? What’s exciting for the future?
Dr. Posner: I think probably a lot of people are interested in this idea of mind-reading, whether you can use imaging to figure out what the person is thinking. Actually, it’s not an interest of mine, but it is I think something that appeals to both scientists, very good ones, and to the laypeople. And there, you rely on statistics a lot because you’re trying to say, can I use the whole brain activity to predict something about what’s the dominant conscious mode?
And that I think is going to attract a lot of interest. There are already several papers about it from people at Carnegie Mellon. It’s not a direction I would want to go in. I don’t know exactly why. And of course, the field is going in many directions at the same time.
One of the main aspects of imaging work that has been drawing the interest of a lot of people who wouldn’t normally be involved in the field of psychology, don’t even think of themselves as being anything like psychologists, but they’re maybe people who are interested in apparatus and methods and so on. And of course, it pets itself. MRI are very important methods for looking at the brain, but probably in someone’s garage, there’s a young person, man or woman who’s looking at new methods that would open up new issues that we can’t even imagine. And that’s a very important aspect of the field right now that it could be new techniques statistical or other for looking at brain imaging, but also new methods of brain imaging that might provide a window on and open up a brand new question. So some things we can imagine and some things we can’t really imagine though, probably all likely to happen if the species is alive long enough for them to happen.
Dr. Sharp: Right. We always have to keep that in mind. It makes me think about all this, you know, we’re talking about attention and how much focus there has been on say things like social media and the attention economy and things like that, how all those technologies are just competing for our attention. I’m sure there’s research being done out there on looking at imaging and smartphones and…
Dr. Posner: Oh yeah, there’s a lot. It’s a very large field of research people doing it. I don’t think things are as dire as most people seem to think about this.
The best studies have compared people who use multiple devices with those who generally don’t use multiple devices. The original study of this sort was done at Stanford University, and it showed that actually, people who use multiple devices were much worse in attention tally, somewhat worse, I wouldn’t say much worse, but somewhat worse than those who didn’t. And it led people to think that the devices were causing a deficit. I don’t think that’s probably justified. It’s probably more likely that people who are attracted to multiple devices, having multiple devices all at the same time. This was not a randomized study because, of course, you really can’t do it. So it does compare people who use mobile devices with those who don’t and they looked like they were different even before the study ever began, and maybe before there were multiple devices.
And so I am not as skeptical about it. The human is very susceptible to environmental influences. And of course, as long as there are multiple devices that are an attractive thing, some major number of people will be using them. And there are some advantages and disadvantages, but I don’t know that they’ll be hindered for their lifetime provided they are getting a lot of good information because you’re getting mostly misinformation and then it could be bad.
Dr. Sharp: That’s another story. Yeah.
Dr. Posner: Yeah, that’s another story. Definitely outside of my field.
Dr. Sharp: Sure. Well, maybe that’s a hopeful note. Our devices aren’t completely hijacking and ruining our brains. Just as we close, I would love to circle back. And you mentioned this memoir that you’ve written and you said that it would be available more widely around the 1st of the year. Is that right?
Dr. Posner: That’s what I think. I haven’t done the proofs yet, and I haven’t gotten word from the publisher about when it will be available. They told me that it would be available on Amazon and other publishers that might do it. And the price, I don’t know whether it will be better, it’ll be low because I’ve already paid upfront for a lot of the costs. And so, hopefully, it will be very low and people in this country will be able to afford it also because so many other countries in which psychology is a popular topic now. So hopefully people, even if they’re not in a wealthy country, would be able to afford it.
Dr. Sharp: Of course. Well, I’m just speaking for myself, but hopefully for others as well that the ability to tap into your experiences and hear everything that you have done over the years is just endlessly fascinating. So I would imagine there will be an audience for this book simply because you’ve seen so much over the years and done so much good work in our field. I really appreciate that.
Dr. Posner: Well, thank you. That’s very nice of you to say.
Dr. Sharp: Sure. Well, I know that we’ve only really scratched the surface here today. There’s so much more that we could have gone into, but I really appreciate your time and willingness to talk through attention, the history there, and some of the new frontiers in attention. I hope people find this valuable. So one more time, just thanks, Mike. I really appreciate it.
Dr. Posner: Thank you very much.
Dr. Sharp: All right, y’all, thanks as always for listening. I really hope that you enjoyed listening to that interview as much as I enjoyed conducting and participating in it. Mike is a great guy, easy to talk to, so much to say, and so much knowledge. I am fully aware that we were just scratching the surface of his experience and conceptualization with attention and memory and so many other things. So I hope that you enjoyed this.
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