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A Neurological Basis for Free Will

Siri Hustvedt: I’ve spent a number of years studying neuroscience, reading papers and first the essential aspect of this for me was learning the vocabulary, learning parts of the brain and trying to put it into a larger context in relation to my studies in philosophy, linguistics and various other subjects, which I think has been extremely helpful and we might begin by thinking about the 19th Century roots of neuroscience and I know that in your work you have mentioned both philosophical and scientific origins of certain ideas, for example, homeostasis.

Antonio Damasio:  That’s a very, very central idea.  Homeostasis is sort of a long word, not terribly beautiful, but it refers… and one good way of giving a synonym of homeostasis is "life regulation."  It is something that has been extremely important in the history of neuroscience, and I think it’s going to become even more important as we go forward.  In the 19th Century, a number of major physiologists, perhaps most importantly Claude Bernard, a French biologist and physiologist, talked about life regulation and talked about the fact that we have inside ourselves an internal milieu; something which is entirely inside the membrane, the covering of our organism and that of course contains all the roving chemistries that allow life to be inside the boundary of one’s body and he talked about the fact that there were very specific forces and very specific processes that regulated this incredible process and made it compatible with life and actually the word homeostasis only came to be coined...

Siri Hustvedt: It’s canon.  Yes, it’s quite late.

Antonio Damasio: Quite late.  It’s in the twentieth century.  It’s much, much later.

Siri Hustvedt: Yes, but in 1915 Freud talks about something very similar and instincts and their vicissitudes in an essay that is not a late essay of Freud’s really. And he is already talking about something that is very much I think compatible with the idea of homeostasis.

Antonio Damasio: Absolutely.  Absolutely and it was something that you know as very often happens in these… with these ideas and with some of these facts.  They’re in the air and different investigators, writers, thinkers take them and use them in their work and sometimes with different names, but they’re there.  They’re the parts of the thinking style and of the thinking apparatus, and in the vocabulary at that time.

Siri Hustvedt:  Absolutely.  It’s almost like an atmospheric condition, so that these ideas and we can get to this later, but I’m very interested in how sometimes ideas seem to be absorbed almost by osmosis, so to speak, as you know unconsciously, not necessarily consciously. But Helmholtz for example, also Freud, was highly indebted to biophysics and to people who came before him, so it’s not as if he invented this idea.

Antonio Damasio:  No, and of course one always has to think also that people very often change their careers as they go along and Freud is a very good case in point.  Freud really begins as a neurologist very much with the same kind of training that I had, except one century before. And it is very interesting that a lot of the formative ideas of neurological training for Freud appear expressed in things that have apparently nothing to do with neurology as such, for example, the sort of tripartite division of one’s mind with the different....

Siri Hustvedt: Yes, the ego, id and uber-ich or superego.

Antonio Damasio:  Exactly.  All of that matches very well and was probably very much inspired by what Freud knew of neuro-anatomy and if he had not known neuro-anatomy, if he had not had to train with the neurology of the time that might not have come the way it did to him.

Siri Hustvedt:  Absolutely, and the fact that somewhat later Freud includes unconsciousness in his idea of the ego I find very interesting and very compatible with your ideas and other ideas that are abroad in neuroscience now, that what we think of as the self or our subjectivity is highly influenced by these unconscious forces, an unconscious part of the self that is not reflective.

Antonio Damasio: Yeah, exactly, yeah and that we are... we are in fact this hodgepodge of non-conscious and conscious processes with some part of our consciousness trying to ride herd over this mess of non-conscious processes and which of course needs to be very clearly spelled out because you have of course the people that listen to something like what we’re saying and say "Oh my God, they’re saying that you have no control over one’s self and one’s behavior and no willpower of any kind." And of course that is false because we do have a measure of control, but it is not true that we have full control and it is not true that when we are executing an action we are necessarily controlling it at that moment consciously.

Siri Hustvedt:  Yes, I think this might be an opportunity to talk about a very famous finding that created tremendous uproar among philosophers and neuroscientists, which is Benjamin Libet’s finding—which is very simple for people who don’t know about this—is that... Subjects were asked to move a finger for example, this finger and Libet discovered that something called a readiness potential in the brain that could be measured was going off about a third to a half of a second if I remember correctly, before the subject had any conscious awareness of wanting to move the finger.  Now this of course became a free will debate and when I read these findings and read other people talking about them I remember saying to myself, "Does free will necessarily have to be, first of all, a fully conscious action?"  I mean if you’re thirsty and you get a glass of water you don’t necessarily have full, subjective linguistic consciousness of getting a glass of water, right, so but also I think you might want to refine this notion of the degree to which a finding like that does not tell us that we have no free will.

Antonio Damasio: Well, it doesn’t because in fact most of the notions that we associate with deliberation and decisions that are important for one’s life are not taken the same way that we move this finger or we pick up the glass.  When we think about important decisions in one’s life, when we think about, for example, what we’re going to do with ourselves in terms of one’s career or what we’re going to... you know, how our relationship is going to be, whom we’re going to get married to or live with, those decisions are not taken on the fly.  Those decisions are, in fact, deliberated. And I love the word deliberated; it’s a word that has sort of disappeared from the vocabulary of decision making studies. But that is exactly what you’re doing.  Sometimes you deliberate for minutes or hours or weeks or months and you do it not in the moment of execution of the action.  You do it offline.  You take yourself away from the moment and you put yourself in a space that in fact competes with what you’re doing in the moment.  One thing that I like to point out is that if you are deliberating, even about something as simple as what you’re going to do this afternoon.  For a moment you say, “How am I going to plan this? I need to talk to three different people and I have only certain number or hours. How am I going to organize this?”  You don’t do that at the same time that you drive and drink glasses of water and other such.  You take yourself away from the perceptual moment and in fact you do that in such a way that others looking at you will get the impression that you are distracted and when somebody says that you are distracted you’re not paying attention.  It means you’re not paying attention to me.  What you’re paying attention is to what you’re going to do. And it’s a very interesting theory because what that does is also give you an incredible inkling as to how and where these processes are going on in the brain, because it immediately serves notice that there is a competition going on between what is in the perceptual brain...

Siri Hustvedt: Phenomenal reality.

Antonio Damasio:  Exactly. And what is in your mind’s eye and ear as you plan stuff and because in fact those two spaces are one in the same, then there is a competition in most brains.

Siri Hustvedt:  Spatially, if we want to use the metaphor, in the brain they aren’t necessarily in competition.

Antonio Damasio:  They aren’t necessarily in competition, so and that is why for example there are all these things that are very well known that people sort of turn their eyes up and sort of look at the ceiling as their thinking or they close their eyes, they close their eyes as they deliberate because if they don’t their eyes they’re going to have the images of the perceptual moment competing with the images that they’re forming.

Siri Hustvedt:  Absolutely and attention is a fairly limited quantity in the human mind.  In other words, you can pay attention to something out there or you can pay attention to what I call the internal narrator, but paying attention to both does not work.  I mean the interesting experience, for example, reading that we both do a great deal of... And suddenly I realize that I am reading the page, I am taking in the words, but my mind has traveled.  This is a familiar experience.  My mind has traveled onto some other subject so that I have some cognitive relation to the page, but it’s not one of semantics and understanding.

Antonio Damasio:  Right, exactly, yeah and there is…  But what is so fascinating is the limitation of this space, is the fact that we don’t have…  In other words, our screens. And you know, I’ve been through hating metaphors that have to do with theaters.

Recorded July 2, 2010

"We do have a measure of control," says Damasio, "but it is not true that we have full control and it is not true that when we are executing an action we are necessarily controlling it at that moment consciously."

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Duke University researchers might have solved a half-century old problem.

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  • Duke University researchers created a hydrogel that appears to be as strong and flexible as human cartilage.
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Predicting PTSD symptoms becomes possible with a new test

An algorithm may allow doctors to assess PTSD candidates for early intervention after traumatic ER visits.

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  • 10-15% of people visiting emergency rooms eventually develop symptoms of long-lasting PTSD.
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  • Using clinical data already being collected, machine learning can identify who's at risk.

The psychological scars a traumatic experience can leave behind may have a more profound effect on a person than the original traumatic experience. Long after an acute emergency is resolved, victims of post-traumatic stress disorder (PTSD) continue to suffer its consequences.

In the U.S. some 30 million patients are annually treated in emergency departments (EDs) for a range of traumatic injuries. Add to that urgent admissions to the ED with the onset of COVID-19 symptoms. Health experts predict that some 10 percent to 15 percent of these people will develop long-lasting PTSD within a year of the initial incident. While there are interventions that can help individuals avoid PTSD, there's been no reliable way to identify those most likely to need it.

That may now have changed. A multi-disciplinary team of researchers has developed a method for predicting who is most likely to develop PTSD after a traumatic emergency-room experience. Their study is published in the journal Nature Medicine.

70 data points and machine learning

nurse wrapping patient's arm

Image source: Creators Collective/Unsplash

Study lead author Katharina Schultebraucks of Columbia University's Department Vagelos College of Physicians and Surgeons says:

"For many trauma patients, the ED visit is often their sole contact with the health care system. The time immediately after a traumatic injury is a critical window for identifying people at risk for PTSD and arranging appropriate follow-up treatment. The earlier we can treat those at risk, the better the likely outcomes."

The new PTSD test uses machine learning and 70 clinical data points plus a clinical stress-level assessment to develop a PTSD score for an individual that identifies their risk of acquiring the condition.

Among the 70 data points are stress hormone levels, inflammatory signals, high blood pressure, and an anxiety-level assessment. Says Schultebraucks, "We selected measures that are routinely collected in the ED and logged in the electronic medical record, plus answers to a few short questions about the psychological stress response. The idea was to create a tool that would be universally available and would add little burden to ED personnel."

Researchers used data from adult trauma survivors in Atlanta, Georgia (377 individuals) and New York City (221 individuals) to test their system.

Of this cohort, 90 percent of those predicted to be at high risk developed long-lasting PTSD symptoms within a year of the initial traumatic event — just 5 percent of people who never developed PTSD symptoms had been erroneously identified as being at risk.

On the other side of the coin, 29 percent of individuals were 'false negatives," tagged by the algorithm as not being at risk of PTSD, but then developing symptoms.

Going forward

person leaning their head on another's shoulder

Image source: Külli Kittus/Unsplash

Schultebraucks looks forward to more testing as the researchers continue to refine their algorithm and to instill confidence in the approach among ED clinicians: "Because previous models for predicting PTSD risk have not been validated in independent samples like our model, they haven't been adopted in clinical practice." She expects that, "Testing and validation of our model in larger samples will be necessary for the algorithm to be ready-to-use in the general population."

"Currently only 7% of level-1 trauma centers routinely screen for PTSD," notes Schultebraucks. "We hope that the algorithm will provide ED clinicians with a rapid, automatic readout that they could use for discharge planning and the prevention of PTSD." She envisions the algorithm being implemented in the future as a feature of electronic medical records.

The researchers also plan to test their algorithm at predicting PTSD in people whose traumatic experiences come in the form of health events such as heart attacks and strokes, as opposed to visits to the emergency department.

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Two different experiments show hints of a 4th spatial dimension. Credit: Zilberberg Group / ETH Zürich
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Physicists have understood at least theoretically, that there may be higher dimensions, besides our normal three. The first clue came in 1905 when Einstein developed his theory of special relativity. Of course, by dimensions we’re talking about length, width, and height. Generally speaking, when we talk about a fourth dimension, it’s considered space-time. But here, physicists mean a spatial dimension beyond the normal three, not a parallel universe, as such dimensions are mistaken for in popular sci-fi shows.

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Vaccines find more success in development than any other kind of drug, but have been relatively neglected in recent decades.

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Vaccines are more likely to get through clinical trials than any other type of drug — but have been given relatively little pharmaceutical industry support during the last two decades, according to a new study by MIT scholars.

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