Entrevista com Mark Solms

For for for it is so important to both your work and the subject of the Hidden Spring and since many people will be unfamiliar with the concept which you introduced I think we should start with just what is quite broadly neuros psychoanalysis um well neuros psychoanalysis arose from my frustration uh when I first trained in neuros Psychology which was in the early 1980s um you might think psychology will be about the psyche um and what is the psyche that is to say what is the mind if not first and foremost something subjective something that experiences

something that it is like to be um but the neuros pychology that I was taught not certainly did it make no reference to subjective experience when I asked questions um about subjectivity uh like for example you know when being taught About the cortical mechanisms of vision um I asked but why does it feel like something to see why why do we unlike cameras experience uh the visual information processing that we um perform and I'm just using Vision like could give you many other similar um equivalent um functions uh and I was sort of discouraged from

asking such questions uh I I was told uh not to ask such questions they are bad for your career Um so psychology um you know neuros psychology uh the word psychology there um is a very problematical one because um it at least is in the in the era that I trained it was still very much influenced by behaviorism and even after the cognitive Revolution which at least allowed us to talk about what goes on inside the black box as it were um we talked about it in a very desicated way you know about these functions

that we Looked at from a S of third person point of view um the mechanisms of let's stick with the example of visual information processing but really nothing uh about the actual phenomenal experiential field um of being um a seeing person so um I I cost my uh eye around looking for uh another take on psychology uh a a a perspective which um at least acknowledged this centrality of subjective experience to the science of the mind and um in psychoanalysis I Found an approach which not only acknowledged it but took it as its starting point

um that was also influenced by the fact that I was doing research on the brain mechanisms of dreaming um and the reason I did that was because the only aspect of Consciousness that was a sort of respectable topic uh in the neuros psychology of the 1980s was Consciousness in the sense of sleep versus waking or or coma versus stupa You know versus of thundered Consciousness Cloud those sorts the level of Consciousness was IR respectable topic so um I did my doctoral uh research on brain mechanisms of dreaming because that's the subjective aspect of sleep that's

the in fact it's a fantastically interesting fact that the unconsciousness of sleep is punctuated by these conscious experiences called dreams so the research I was doing on The brain mechanisms of dreaming led me to uh realize or recognize that some of the claims of psychoanalysis in respect of Dreams were not as far-fetched as as they had initially appeared to be so I I was I I I think from these two directions I was drawn to psychoanalysis the one was I was doing sleep and dream research uh I I made some unexpected discoveries which suggested that

maybe the psychoanalytic approach deserved a little bit more serious attention than We'd been giving it um and then looking at psychoanalysis I realized well this was an approach to the mind that that took uh that took subjectivity seriously so neuros psychoanalysis is just um a word that refers to an approach to neuros pychology which which doesn't mean neuro behaviorism or neurocognition it means neuros subjectivity the most interesting aspect of neuropsychology that that's a um I I hope an adequate answer there's a lot More I could say but that is the the absolute essence of the

of the thing no no no it's it's quite adequate I have a few thoughts so first when you mention the other psychologist or perhaps it was neuroscientists who were saying don't ask these questions it's it's bad for your career I just spoke with David Spiegel here at Stanford who does a lot of hypnotherapy and his father was the uh I don't know I mean I know Freud did some did some work in hypnosis but I Think David David's father brought hypnotherapy into the modern four and when he started doing it people were saying don't ask

these questions stick to psychoanalysis so it's funny how like the trends in Psychology how they shift in this way but just to clarify then or or paraphrase so neuros psychoanalysis arises out of this tension between the third person view of the mind that something like Neuroscience gives us and then our first person experience of Feeling and sensation because it seems like the former can never get to it in a way or doesn't treat it adequately no that's exactly right uh psychoanalysis for all of its faults because you know let me uh State as quickly as

possible that I'm not a True Believer in the in the sense that so many psychoanalysts are there they they really have sequestered themselves from the mainstream mental science and haven't stay depressed of you know everything That we've learned since 1939 and which is when Freud died um so um for all of its faults psychoanalysis has developed um from its method uh which is free association in other words a sort of a sort of naturalistic sampling of the stream of Consciousness in in relatively controlled conditions from that uh they've developed a whole um theoretical uh infrastructure

with with a with a vocabulary a conceptual Vocabulary for for thinking about and talking about uh the the the subjective um perspective upon the mind and I thought that's a good starting point if we're going to have a neuroscience that that um can accommodate these things let's build upon what that tradition uh bequeathed us and so I spent a good deal of my scientific life trying to find the neural correlates of the the um major psychoanalytic uh Concepts derived from the study of of subjective the lived Life of the mind um and that naturally of

course means the reverse translation too uh trying to uh bring into psychoanalysis um what we've learned in the neurosciences about the very same things that they are interested in using other methods so it's it's been an attempt to sort of bring the psyche into neuros pychology on the one hand but then also to bring more scientific rigor to bear um on psychoanalysis well you you mentioned That you're not a mainstream psychoanalyst in the sense that you've actually taken in the developments of Neuroscience since Freud death but one of the most fascinating elements of the Hidden

Spring I mean before we get into Consciousness for me was that you think of Freud as a neuroscientist which I don't think is in the Zeitgeist anymore and dispelling this or perhaps explaining in just what sense you mean this should do a lot to Dispel people's misconceptions about Freud like a total Mystic who wasn't doing science well um I I told you that when I was doing my dream research I became uh aware of um the extent to which Freud had um made some claims about it which were consistent with the what I was Finding

in in my research uh the I became aware of that uh through a seminar that was taught in fact by a philosopher um but it was a seminar on a Unpublished or unpublished during Freud's lifetime um he was doing a seminar on an unpublished paper uh or manuscript uh that was entitled a project for a scientific psychology which was Freud's attempt penned in 1895 uh to um to delineate what the uh neurophysiological mechanisms might be of the the sorts of things he was observing clinically when I say the sorts of things he was observing clinically

I mean what he was observing Clinically as a neurologist studying what we nowadays call functional neurological disorders um the word functional neurological disorders um covers um essentially covers what in Freud's day was called hysteria patients uh with so-called hysteria present to neurologists uh because they have what appear to be neurological symptoms paralyses um amnesias um you know loss of the ability to speak and so on so they look like neurological Patients but then it turns out there's there's no structural damage to their brains so that's why they're called functional neurological disorders so Freud as a

neurologist became interested in these patients which by the way I mean I work in a neurology department uh we see them every week I mean this is not an uncommon condition um so it's it's no surprise and it's fascinating it's no surprise that Freud you know was working with those sorts of patients but The point I'm emphasizing is that he was a neurologist um and uh he was a neurologist after uh he was a research neuroscientist uh he he he went to medical school rarely with scientific interests rather than clinical ones uh and he did

some extremely um good research on what uh what is probably best called neurohistology in other words the structure of the nerve cell then he did very good basic neuroanatomical research starting with Very lowly invertebrate creatures and and and low vertebrates primitive fish um like um uh the lampi U studying their spinal cords and the and the intimate structure of the Spiral cord gradually moving up toward the brain stem and with that gradually moving uh to human brains um until uh he he he realized he wasn't um going to be able to make a living he

wanted to get married he wasn't going to be able to make a living as a neuroanatomist and so he went uh uh he He took more seriously the clinical part of his studies and uh then qualified as a neurologist and made fundamental contributions to the study of um cerebral poies you know the um movement disorders of childhood um and ultimately moved up U the to the higher cortical functions and and did a a very good study on Aphasia um in 1891 so given that background you know the background of a histologist an anatomist a a

a a a a clinical Neurologist making you know a substantial contributions to the field and ultimately a neuros psychologist when he studied um language brain mechanisms of language it wasn't surprising that he wanted to um he wanted to understand so-called hysteria um in in neurophysiological terms and that's why he wrote that project which is the most of his papers that I read um now ironically U the reason that Freud Abandoned neurophysiological approaches uh was because in his attempt to delineate the brain mechanisms of functional neurological disorders he had to recognize that it was pure speculation

uh in 1895 we just didn't know enough or we knew practically nothing about the dynamics of the brain uh the function uh the functional organization of the brain when there's no structural lesion we just knew next to nothing about it so he Was wildly speculating in that 1895 paper and was then compelled to recognize against his his own prejudices uh he was compelled to recognize that the and this is why I say it's ironical that if you want to have an empirical approach to the problem you should stick to psychological data because that's the only

data that we had um and so he abandoned uh reluctantly U his attempts to um to understand these things neurologically but always said from then Onwards um that one day uh there will when there advances in methods um that uh it will be possible to to study the apparatus of the Mind as he called it um you know from a physiological and anatomical point of view and so I recognized that that uh that future that he was looking forward to that I was living in that future um you know so so uh that's why I

I made it my business to to try to rejoin psychoanalysis with the neurosciences uh which is what Freud had Always imagined would be possible I'll tell you one other thing I am actually in the middle now uh of the Translating all of Freud's neuroscientific writings into English it's going to come out as a four volume set because there are a lot of neuros FR published from 1877 until 1900 uh in neuroscience and and neurology journals and if you count uh a small review articles they over 200 titles so you know Freud was very deeply steeped

in The neuroscience and Neurology of his time and when one of his psychoanalytic um colleagues in 1936 um the guy's name was Rudolph Brun who was also a neurologist uh became aware that Frey had produced so much neuroscientific research in his early years uh he he said to Freud you know why why don't you ever talk about this this is fantastic stuff and for said well at least I hope it will make people realize that I Didn't pull psychoanalysis out of my hat uh parenthetically is that what you're doing in I you mentioned that you're

on your sabatical in Germany is that is it mainly to be working on these translations that's exactly what I'm doing here yes very nice and then yeah I guess just to paraphrase again and make sure that I'm totally on the right page but what struck me when I was reading the Hidden Spring again was that this is the paraphrase part he totally Freud Totally believed that the mind was biological mediated in the brain so again nothing mystical but that really just due to the limits of neuroscience at the time he sought another method to get

at the underlying unconscious dimensions of the mind and that this is what psychoanalysis emerged from but as you just said he suspected or expected that at some point science would develop to the point where these things would merge again and that is what you're Working on now yeah um he um he when you speak of the unconscious dimensions of the mind I would like to just elaborate a little bit on that point uh Freud said uh that that what he was interested in doing uh is inferring from the conscious phenomenology of mental life he wanted

to infer what the mechanisms were that underpinned those uh conscious states he called that meta psychology in other words Beyond psychology in the sense of Beyond Consciousness what lies Beyond Consciousness and he said since you're a philosopher you might find it amusing he said I want to transform metaphysics into metapsychology in other words he wants to have a rather than a philosophy of mind you know he wants to have a science of mind where we infer the underlying uh laws governing uh the observable surface of of conscious phenomena and um the point I'm leading up

to is this that what Freud called Metas psychology uh was an attempt to describe the underlying functional organization of these abstract entities uh like memory systems perceptual systems executive systems and so on uh in other words the very same things as we're interested in in cognitive Neuroscience today you know there's a we don't study the brain as a as a thing uh you know as a as a as a visual tangible thing we study its functions in order to be able to infer its functional Organization that is the common ground between a neuroscience and psychoanalysis

this the functional organization of of what Freud called the mental apparatus um and uh I think that um if we only approach it from an external point of view in other words if we treat the brain only as an object and not also as a subject then we're going to miss something fundamental about this part of nature because uh as far as we know it is the only part of nature that Has subjective experience uh presumably there's some reason why it feels like something to be a brain and not like anything else uh in other

words nothing else feels like being itself it's only brains that have this uh this remarkable capacity and presumably it evolved for a reason presumably subjective experience does something and if we leave that out of account I think we're going to be grossly misled in in terms of our understanding of the functional Organization of the brain if we don't build into our understanding of its mechanisms what can be learned about those mechanisms from the subjective point of view uh in other words what can be learned about what the subjective manifestations are all about then I think

um we'll never understand the brain if we treat it with the same as the liver no that's a that's an extremely interesting point I mean we're not just Trying to dissect brains and figure out their ultimate makeup because that would just I mean ultimately devolve into something like physics but we're trying to understand what it does and that's all about inference it's all about connecting what we observe in the brain to I think what you said what it what it does and that comes from something like psychoanalysis where you're really getting at the subject and

what what's what feeling is going on is inconscious Yeah let me let me be clearer than I think I was I I I'm actually saying two things there the one is that we're not just interested in observing the organ we're wanting to infer its underlying functional organization that's the first thing but the second thing I'm saying is that that underlying functional organization must also explain why the brain has a subjective aspect you know why does the brain why is there something it's like to be a brain and Not something it's like to be anything else

I'm saying there must be something fundamental about the brain uh that that makes it sentient and uh so I'm saying I don't think we will understand the mechanisms governing the behavior of the brain if we don't centrally uh include in our attempts to understand those mechanisms uh why those mechanisms give rise to experience well now that you've raised the question why is there something it's Like to be a brain I think we can turn more to the focus of the Hidden Spring so maybe we should begin then with the purpose of the book and your

investigation and that raises the question of what is the hard problem of Consciousness if that is what you're trying to show ultimately is not so hard as it seems yes so the hard problem of Consciousness as formulated by David Charmers um is that an understanding uh of the of the the very thing we've just Been talking about an understanding of the mechanisms um which govern the behavior of the brain he says we'll never explain phenomenal subjective experience he he seems to suggest that experience uh lives in some parallel universe uh that that that is not

reducible uh to to the laws um of that sort of natural mechanistic laws that we that we use to explain everything else in nature so he's saying that Neuroscience um goes about and including Cognitive Neuroscience goes about its business as if it were studying anything else in nature in other words it it it takes the phenomena then uh reduces it those phenomena to an explanatory causal model U mechanistic account of the functions and depending the phenomena and then it thinks its job is done and charma says it its job is not done uh in in

respect of one crucial uh fact about the brain namely uh that it experiences because those mechanisms do not account For the experience why does he say that well I'll I'll I'll quote in simplified fall because I I I I I don't want to go down all the repol but in simp implified form I'll quote um Frank Jackson's knowledge argument which which um Charmers invokes in this very um respect um Jackson said imagine a visual neuroscientist Nam Mary uh who knows everything there is to know about the functional mechanisms of visual information processing she knows Everything

that goes on from the light waves being transduced uh into neural impulses where they transmitted through the lateral geniculate to the cortex what the how the cortex the visual cortex processes this information in multiple different streams she knows all of that all about the functional mechanisms of vision but she's blind so she knows nothing about what it is like to see and then one day uh the gift of sight uh is bestowed on her and So she suddenly uh after all these years of studying Vision uh now she experiences vision and uh Jackson's uh argument

is at that point Mary will learn something utterly new about Vision that even though she knew everything about its functional mechanistic organization how visual information is processed uh that knowledge gave her no uh preparedness for the the phenomena that she's now dealing with namely the the qualitative experience of seeing of What it is like to see and the inference that Jackson draws from this and that Charmers builds upon is that therefore a functional mechanistic account of what the brain does does not explain why it feels like something to be a brain um and then uh

there's a further uh inference that therefore the experiencing must exist in some other dimension you know it must not be reducible to the ordinary mechanistic laws of science like like everything Else is so that was my starting point was um is that is that really so is it really so that that conscious experience is not part of nature that that that can be understood uh in the same way as all other parts of nature uh can be and um my um the starting point of my attempts to tackle that that problem uh was the observation

that Vision which I must say it's not by accident that Frank Jackson spoke of marry a visual neuroscientist because The main um effort uh since um well since Crick really since the early 1990s the main effort to find the neural correlate of Consciousness um has focused upon Vision uh we understand uh the the cortical mechanisms of vision better than we do any other perceptual modality so the idea was crick's idea was that if we can crack that how does a cortex generate visual experience then we can generalize from there to experience uh Al together in

other words To Consciousness more broadly my my belief is that's the wrong place to start uh for the reason uh that vision is not an intrinsically conscious process you can see perfectly well without being conscious of what you're seeing um and in fact that is why Mary is able to understand all of the mechanisms whereby Vision occurs because Vision can occur and does occur all the time in us um without any awareness some visual Processes are conscious but the vast majority of our visual information processing is not conscious what is more um the consciousness uh

in Vision to the extent that vision is conscious uh it's not intrinsic to the cortex the cortex is not intrinsically Consciousness generating the the information processing that goes on in the cortex is rendered conscious by it being activated by it being aroused and modulated from below from Brain stem structures uh uh in particular the reticular activating system now the reticular activating system from whence all Consciousness flows it's a absolute prerequisite for any form of Consciousness that um it has to be activated from the reticular activating system this part of the brain unlike the cortex in

general and the visual cortex in particular its whole function is to generate Consciousness not visual information processing but Rather the rendering conscious of visual and all other forms of information processing so I thought that we had started in the RO Place uh looking at vision and cortical Vision uh as our model example of Consciousness was an unfortunate place to start because it is not an intrinsically conscious process so I I I I started from the the the other end of the um apparatus as it were the the bottom end rather than the top and also

I I thought why start with the Most complex forms of Consciousness you know the human cortical Consciousness is the most complex form uh that we that we know of why not start with the elementary form this basic prerequisite form uh from which all upon which all the high other higher forms are are built so um that that's the title of my book The Hidden Spring refers to the the the upper brain stamp which is which is from when cons all Consciousness Sprints the reticular activating system yeah yeah that's might be slightly simplifying it because the

reticular activating system um is not the totality of the the arousal structures of the brain but that that's the heart of the matter you know there there are a few other structures like for example the basil for brain nuclei and so on which which perform exactly the same sort of function but they all deep um subcortical structures um that have the Function of arousing and modulating uh the rest of the brain well a a few comments one Frank Frank Jackson has been on the podcast a number of times and it is funny that I mean

I think he is kind of annoyed by the Mary in the white room thought experiment at this point because he is so well known for it but he's also like totally repudiated it and doesn't agree with it anymore but also another comment I hadn't realized I mean you Have this very wonderful extensive discussion of chmer CH Chalmers and the hard problem in your book I think it might be chapter 11 but I hadn't realized that chmer thinks or at least at one point thought that the hard problem would eventually be solved I hadn't realized that

maybe I wasn't reading it closely enough myself but okay now returning to the direction in which we were going so the cortical dimensions of Consciousness are Generated in some sense by the reticular activating system of the brain stem and there is a ton here I mean a tremendous portion of the book is devoted to this the role of the cortex in Consciousness how this has been ined investigated with animals and Hydra andic patients and hopefully I mean maybe we'll get to touch on that but it all starts with dreaming and you talked a bit about

this at the beginning of our conversation but the the history of the study of dreaming Is extraordinarily rich and interesting in itself but the subject of for another time but what makes maybe you could say more about what makes understanding the neurological source of dreaming at all relevant to understand in Consciousness and what we've just been talking about I told you the cat would be making some of my best friends are cats don't worry about that uh the the um I said uh some minutes ago that um I was interested in dreams because they Are

conscious states that occur uh in in the midst of sleep I mean it's it's truly fascinating that while we're unconscious which is a sort of definitional U almost of sleep is that you're unconscious um you know that that that this unconsciousness is punctuated by these intensely conscious experiences so uh when I sought the brain mechanisms of dreaming um let me say first of all at that time I began my research uh on that subject uh in the Mid 1980s and at that time um the standard view was that the brain mechanisms of dreaming were identical

with the brain mechanisms of R sleep um REM sleep is generated just to put it very simply uh by uh miso pontin tegmentum cells part of the reticular activating system which um are colonic so the neurotransmitter or rather I should say the neurom modulator um that is sourced there is a CLE Which activates the forbrain and according to the standard model of that time which was alen hopson's model uh it activates the forbrain uh sort of chaotically and randomly because this is this is very widespread activation from the misop pantic mum and the cortex you

know to quote uh Hobson makes the best of a bad job it's got all of these sort of activ the images perceptual uh images of various modalities and thoughts and feelings and whatnot and intentions are All activated at the cortex being the organ of the mind that if you activate it you're going to organize you're going you're going to activate mental contexts and his view was that these are then just joined together uh that there's no that's the synthes speaks of activation synthesis they said the cortex's job is to synthesize these um randomly activated cortical

elements and he made the the point that um the dream it is so nonsensical so Unrealistic U so utterly like our ordinary experience precisely because it's randomly generated you there's no intrinsic meaning it's not really referring to anything going on in the outside world this is endogenous activation from the bra stem and so it creates this chaotic splodge and he says that the dream is therefore like an ink plot there's no meaning in it uh it's not psychologically motivated um you can come to that ink plot after the fact and You can find meaning in

it in other words you can project meaning into the ink plot but the ink plot uh itself is is is Mindless meaningless without intentionality and um and he also emphasized the fact that atile choline is to use his phrase motivationally neutral so my um studies uh which differed from his in that I didn't study rats but rather human beings um the the main subjects of REM sleep research had been Rats and cats um which is for all sorts of good reasons that that they they they focused on these animals but um the downside of of

studying them is they can't speak and therefore you can't monitor the subjective side um or takes us back to the very starting point of our discussion you leave out the subjective observational perspective so that's why I studied human beings I wanted to know how are how are the contents of greens altered by damage to Different parts of the brain and that led me to the absolutely uh surprising discovery that patients who lost uh the capacity to uh generate REM sleep nevertheless retained the capacity to dream uh so you can dream without having any R sleep

uh and what is more I found that there were other patients who lost the capacity to dream in whom there was a preservation of REM sleep so these are not the same thing REM sleep and dreaming uh are are what we call uh Doubly dissociable functions so my interest then uh turned to uh the brain mechanisms that generate dream as opposed to the bread mechanisms that generate REM sleep and uh the main mechanism there turns out to be something called the misoc cortical misol liic dopamine circuit which is sourced in the reticular activating system in

an area called the ventral tecmental area and Rises up from there um into subcortical motivational Structures and Beyond now um I told you what it's called but another functional name for this is to is the brain reward system I mean this is anything but motivationally neutral uh it is uh intensely motivating positively motivating uh system um hence the name brain reward system uh it's also been called all sorts of other things seeking system wanting system uh curiosity interest expectancy system and so on so um my uh search for the brain mechanisms Of dreaming uh brought

me to this system which was as I've already told you what made me uh realize perhaps Freud was on to something when he said dreams were motivated mental States uh but also to another fact which is that the reticular activating system although it has an arousal function as we've known since 1949 U this arousal generated by the reticular activating system is not motivationally neutral it's not just blank wakefulness um it is intensely Affective um this this circuit is just one example the one that turns out to be the driving force behind a a dream generation

but the same applies to many other reticular activating circuits so for example so the one I'm talking about uh is is is modulates dopamine uh but um the one that modulates serotonin which plays such a pivotal World in treatment of depression um it's also sourced uh in the reticular activating system likewise Norepinephrine which plays so norepinephrine you you psychiatrists fiddle with it to treat anxiety they fiddle with serotonin to treat depression they fiddle with dopamine to treat psychosis these are not the sorts of things that an theists are interested in these are the sorts of

things psychiatrists are interested in because they have to do with feeling with emotion with with AET so my dream research led me to the brain Stem um because this system is sof in the brain stem but it also led me to the realization that the arousal that emanates from the brain stem is not neutral it's not just quantity of wakefulness it's not just a level of Consciousness it has content and it has quality and uh that uh content and quality is affective so we'd known since 1949 that all Consciousness is contingent upon brain stem arousal

uh but what these findings and it wasn't Just my dream study my dream study led me to a a a body of literature which was then beginning to develop independently of my efforts led by a somebody who ended up becoming my closest colleague in consequence of this named the AR anip uh that that he was is uh demonstrating that um all basic affective States raw feeling States um are generated from upper brain stem mechanisms so that's where dreaming fits in uh and and brings us back to the Topic of the Hidden Spring I said to

you earlier that I thought we were looking in the wrong place that we uh if you want to understand the mechanism of Consciousness you shouldn't look to the cortex and to Vision because the the the mechanism of cortical vision is not intrinsically cult cultes but the mechanism of brain stem arousal is intrinsically conscious and what is more it produces a particular quality of Consciousness or range of qualities uh That we call affect and so I came to the view um that if we want to understand Consciousness we need to understand its most basic form namely

affect and that this is is the right place to start not only because it's its most basic form but also because it if you understand the mechanism of feeling then you have to explain why it feels like something unlike Vision you know you can understand the mechanism of vision without knowing why it has to feel like Something to see but you can't explain the mechanism of feeling without explaining why it has to be felt if Mary were an affective neuroscientist um and she understood all the mechanisms U of how how feeling is generated in the

brain she would have to explain those mechanisms would have to explain why they feel like something that's the whole point of those vectors so so that's that's sort of um that that takes us to pretty much The heart of the argument of what the Hidden Spring is about as in a I mean there's often a a question is raised how can you tell if some sort of organism is capable of Consciousness now we're able as far as I can tell to tell if a creature is Dreaming by examining the whatever is going on in their

brain If is it the case that anything with the reticular activating system in the upper brain Stem is capable of dreaming um well the problem is unfortunately more complex than the way you've just framed it um I'm happy to agree with you uh but but many people would not be happy to agree with you because they would say just because you can see uh that the upper brain stem is activated during sleep uh and that you can see that they dis activating the cortex and you can even see as we have been able to recent

years using some of The wonderful techniques and methods that we now have at our disposal you can even show that there are things that were learned during the day you see the same pattern in the hippocampus that night during dreaming sleep as you saw being acquired during the dream day you can see also the patterns in visual cortex that coincide with the uh images uh that human beings report thought they had seen during the dream so there's all sorts of good reasons to believe that This sort of neurop physiological um evidence of dreaming is indeed

just that evidence of dreaming nevertheless many people will say well that's not a dream that's just activation of certain parts of the brain you know you can't be sure that there's actually a dream attached to that but if we if we you know detach ourselves from that problem of other Minds is basically what that is um that you know you have to be the dreamer to know whether they're dreaming if we Detach ourselves from that um philosophical conundrum and just look at it purely scientifically then yes indeed um all the evidence suggests that all mammals

dream um all mammals all of the um architecture uh uh in the human brain that we know is responsible for dreaming all of the phys ological processes that we know coincide with dreaming uh all of those things happen in all level species so there's very good reason to believe That all levels stream but then there are other animals with brain stems like fish or amphibians or uh birds do they do we also have reason to think that they dream and what I'm getting at is if the same source of dreaming is the source of Consciousness

we might have at least good Prima fascia reasons for like classifying okay these are the conscious animals these are nematodes we don't count them they don't have a they don't have a brain stem yeah I want to draw a distinction here between uh dreaming Consciousness and raw feeling um dreams are suffused with feeling but they also uh include um complex uh uh perceptual experiences which are not just feeling they are they are um things that we see and hear and think Etc um that's something in addition to the raw feeling these properties of Dreams must

be contributed by the cortex um the cortex is where it's the it's the activation by the Braid stem of these cortical structures which enable us if you don't mind me putting it this way to feel our way into those cognitions so the cortex is is producing these complex representational um gymnastics uh and the upper brain stem U modulates them uh and in this way we we we we render them conscious so if we separate those two bits I would say all mammals um there's every reason to believe that they dream because they Have both um

upper brain stem structures of the kind I'm talking about and they have cortex um when it comes to to um uh Birds uh and and and uh several other vertebrate species they have a pallum they have they have a homologue of Cortex uh but many nonvertebrates have no I mean many um vertebrates non-mean vertebrates don't have uh anything cortex to speak of so I would say that all vertebrates have raw feeling uh but I wouldn't I wouldn't claim they all Have dreams I would say they all have raw feeling and again I have to say

um every prediction arising from that hypothesis is confirmed um like for example um you stimulate the structures which generate pleasurable feelings the brain stem structures which generate pleasurable feelings in humans you predict predict if I were to stimulate this structure in a fish um it is going to um it is going to seek to repeat that stimulus so if you give them a little Leave that they can prod with their with their schnars uh you predict they will keep prodding that lever that s that switches on the electrode because it feels good um and that's

what they do and conversely with abive stimuli which are um generated in the in the parts of the brain stem which which produce uh unpleasant affect uh they avoid uh those uh those levers so I'm just giving you one silly little example in fact let me give you a better Example zebra fish um or zebra fish as you got say um you you you they have the same brain stem architecture being vertebrates and um you put them in a tank uh and you put all the food uh on this side of the tank they tend

to congregate there that's called conditioned Place preference Behavior they prefer to be there because that's where the food is now on the other side of the tent you introduce cocaine uh cocaine uh is not good for you it's not Nutritional uh but it feels very nice to IDE cocaine so uh a prediction arising from the hypothesis that zebra fish have feelings um that prediction is that they will start to congregate where the cocaine is um and that's called holic Place preference Behavior they're conditioned by only by a feeling not by any anything that's nutritionally good

for them and that's exactly what they do uh the fish head for the cocaine and the same applies to morphine and the same Applies to amphetamine and the same applies even to nicotine um zebra fish like those substances so you know these these are the kinds of this is the sort of evidence I'm referring to when I say that all of the predictions arising from the hypothesis that all vertebrates have all feelings uh every time we ask that question the answer we get is yes well going back in time a few minutes uh to when

you raised this distinction between the raw feeling and Affect of the brain stem on on the one hand and then everything else that happens in the cortex maybe now would be a good time to talk about some of those or some of that very interesting Research into cortical Consciousness or just more of this distinction between the two and in particular i' I'd love to hear about those Hydra and calic individuals that I mentioned earlier there's this really interesting well there there are plenty of terrific Figures in the book that make it much more readable and

engaging and there is this one pair of pictures I think of a hydralic girl and she's just sitting there and then in the next picture you've like or not you but somebody placed her baby brother in her hands and you just see her light up and my understanding is that a hydralic individual is missing I don't know if it's all of their cortex but a substantial portion of it but this pair Of images really indicates the how the affect or the raw feeling is centered in the brain stem which is still intact in this girl

yep well let me say a few things a few preliminary things about that first of all that girl uh that she was a three-year-old kid she had no functional cortex at all um there are some um hydran andelic children who have remnants of Cortex um there are some who don't even have subcortical B or ganglia they have no for bread not only no Cortex but no for bread at all of course it depends you know the hydrin hyran andil is not a disease it's a it's a consequence of various different types of disease process so

it it vares in its expression but the kid that uh is photographed in my book and whose scan is shown in the book has no functional cortex share has a little flange of Cortex um sort of temporary occipital cortex but it's completely glyos um and there's no white matter connecting that Cortex to the thus so it's just it's just a Remnant it doesn't do anything it demolish doesn't do anything so these and it's also important to point out that this is not just an individual case I mean this is she's typical um of what you

see with these kids with no cortex they not only are they awake um you know in the sense of having a sleep wake cycle uh they they they are responsive the definition um I mean obviously a patient in coma is Completely nonresponsive uh but uh the reticular activating system um is supposed to produce this level of Consciousness as I said a sort of quantity blank wakefulness so the prediction if the upper brain stem produced only a blank wakefulness the prediction would be that these kids um should have a condition which is called persistent vegetative state

also known as nonresponsive wakefulness please note Nonresponsive so these kids wake up they go to sleep so they they they they have um a wakefulness but it's supposed to be blank if the theory that the upper bread stem doesn't have quality and and and content uh but these kids are responsive so she responds to her little brother being placed on her lap she responds she like all of her equivalent kids with the equivalent condition she responds in emotionally varied ways uh and in Emotionally uh uh varied ways that are that are appropriate to the stimulus

so if you take that little baby brother away from her she arches her back and she complains you know she she she's annoyed if you take her brother away from her if you if you give her a fright she startles and cries um you know and Etc so she's she's capable of a wide range of basic emotional states and um and and this is what we see in all of these kids by the way we See the same thing in decorticate animals it's it's been known for a long time that you can you can demonstrate

the presence of all all the basic emotions in mammals that have no cortex it's just it's so much more striking when you see it in a human being these kids are fully emotionally uh responsive and uh and they they they do not have any functional cortex so that for me um pretty much clinches the the the deal that that that we've always Known that the basic form of conscious upon which all other forms um depend is upper braad stem arzal these kits show that that upper bread stem arousal is affective arousal it's emotional arousal feeling

States and um it's not only on those kids that we BL uh that that claim you know it's um there's there's many other lines of evidence from other methods um for example um because let me just say um many people say how Do you know that the child doesn't just behave as if she's conscious you know as if you know they invoke the kind of philosophical zombie argument you know she might look and and behave as if um she has feelings but maybe inside nobody's home so to get around that problem of reportability she can't

report on her on her mental States um we use other methods um I can mention many of them but let me just mention one here uh that if you stimulate with an Electrode those deep brain stem structures as I was saying earlier uh we do in fishes and uh we get the behaviors that we expect it's because we know what happens if you stimulate those structures in human beings uh they report intense emotional states I mean really intense um you you get the greatest intensity by far and the greatest variety by far of emotional states

by stimulating those upper brain stem structures stimulate Cortical structures you get really pale imitations of of feelings um more like thoughts about feelings or memories of feelings rather than actual real raw feelings so it it's it's there's all sorts of lines of evidence that converge on the conclusion that the upper brain stem generates raw feeling itself well with uh with a book of this depth and richness there's always so much to talk about and we could have spent the entire time just talking about I mean the first chapter Freud and Freud in Neuroscience or Freud

in dreaming but in the interest of time and making sure that we get to what Consciousness is I I want to turn back really quickly to to the Hidden Spring and something you say in the introduction which is that so we share it with fish and it has an evolutionary origin and you also mentioned that many scientists and philosophers believe Consciousness doesn't have a Purpose so in philosophical jargon we might say it's epiphenomenal but what then granted everything we've just been discussing about affect for instance that's where a affective Consciousness stems in the upper brain

stem what is the purpose then that Consciousness has and how does this maybe relate to its evolutionary origin okay thank you um let me start by saying that the fundamental difference between living and non-living things is That living things resist the second law of Thermodynamics and other words they don't dissipate uh they don't just equalize uh with the their environment they work at staying within certain parameters um so for example um we have to stay within a certain temperature range we have to stay within a certain oxygen range we have to stay oh is that

a hand up it's a hand it's a hand I just wanted to note that in the book when I was reading I had not made this Connection before that specifically that homeostasis is is sort of anti-entropic in a way and I just thought that this was like a brilliant connection I loved it thank you yes sorry for cutting you off I just not at all I mean it really is it's a fundamental Point um that uh it it it there is literally no living thing that is not governed by homeostasis it is what distinguishes us

from non-living things uh that we're actively working against entropy uh and And and seeking to stay within um what are our viable bounds um and so homeostasis is what keeps us within those viable bounds now um we are born with reflexes or instinctual behaviors um that uh if we move out of say for example you move out of your preferred temperature range you get too hot uh then those reflexes kick in you perspire uh and you pent you breathe more rapidly and Shallowly those two things cool you dark um and the same applies to all

the other homeostats that this is what the autonomic nervous system does it's got these automatic mechanisms reflexes which which respond to homeostatic deviations and maintain you in your viable bonds now um that's all well and good um uh if you are in the sorts of environmental conditions that those reflexes predict uh and if you don't mind I have to here introduce the word Prediction because that's essentially what reflexes are they are actions that predict uh returning if you perform this action uh it is predicted you will return to your viable BS but this doesn't always

happen so um that's if you're in unexpected unpredicted uh environment so I I'll use the example I use in the book imagine Well normally when you know you breathe you you need your your your blood oxygen level in relation to your blood carbon dioxide Level have to remain in a certain ratio and uh you do that very easily there's a reflex uh which your brain is constantly monitoring your your blood gases and that reflex expands your intercostal muscles and then lets them go and then expands and then lets them go and what that does is

it brings in oxygen and it expels carbon dioxide brings in oxygen expels carbon dioxide you do that all the time automatically until we started speaking about it now you weren't aware That you do it doesn't need any Consciousness it just happens um but now you find yourself in the unexpected situation of being in a carbon dioxide fill R um you you you've never been in a burning building before let alone this particular burning building um you don't know what to do um so what mechanism do you use um the the the at this point and

this is a crucial point at the point that you move into unexpected uh circumstances like that you suddenly Become aware of your need for oxygen and we call it air hunger or Suffocation alarm it's a very unpleasant feeling and the purpose of this I'll say purpose theologically because this is why it was selected in the the the creature that uh that de that that that developed this capacity developed a massive adaptive Advantage which is that you can feel your way through the problem if you're aware um of how well or badly you're doing in terms

of Bringing yourself back into homeostasis um then you can predict your demise before it's too late uh you if say for example you go upstairs you find that there your air hunger gets worse um that's because there's less oxygen there but it's the feeling that tells you there's less oxygen there then you go downstairs and your your respiratory distress decreases because there's more oxygen there that feeling has had a very substantial biological causal Consequence which is that you stayed alive rather than died um so that's the Adaptive advantage that feeling bestows uh not to put

too fine a points in it it bestows the capacity for Choice um otherwise all that the organism could do is stochastic random Behavior so my reflex isn't working so I behave random and then some subset of the of the fedot type uh will uh randomly do the right thing they are the ones that will survive and reproduce all the rest over Will expire uh and then the next generation will have the polymorphism that made that subset of the species do the do the right thing and so in future they will have a new reflex which

bestows a um advantages on on that subset of the species but remember it comes at the cost of mass extinction uh what feeling bestow is the capacity to do something which enables you to remain within your viable BS not randomly but rather by Choice uh and any choice has to be granted in a value system there has to be some value which makes one action good and another action bad otherwise it's not Choice it's random so a value system uh well actually the value system fundamentally is the value system of the whole of of um

natural selection namely that it is good to survive and bad to die so that value system is broadcast subjectively and please note it's broadcast subjectively to the gree To the organism um this is going well for me or this is going badly for me um the feeling tells you you've made the wrong choice uh so you change your mind uh and you go the other way and then the feeling tells you you've made the right choice so feeling um underwrites Choice which which in turn uh yields voluntary Behavior so voluntary behavior um is the is

the enormous Advantage uh that feeling U um contributes and this is not Something epiphenomenal uh this is something with massive as I said earlier massive biological causal consequences nothing could be more biologically consequential than dying um so uh the prevention uh of of dying uh is is pretty causally consequential as far as um living things are concerned that's what feeling that's what feeling does that's what it's there for uh and I say again what I said earlier about David charma's hard problem he says that no Mechanistic account of any cognitive function uh will uh explain

in advance why it feels like something and uh I emphasize the word cognitive there that's true no mechanistic explanation of any cognitive function will uh explain in advance why it feels like something but that does not apply uh to an affective function like feeling um the the mechanism of feeling just does explain why it feels like something there's no point of having a feeling if You don't feel it it's the it's this becoming aware of how well I'm doing uh and I need to emphasize again that it is intrinsically subject you know it is about

it's only of the values I speak of are only valuable to the organism you know it's a it's not something that applies uh to the universe it's something that applies to me how well am I doing uh in terms of my survival um and so I'm monitoring my uh oxygen uh level and feeling it uh so get in other Words bestowing value on it so that I can make choices about my behavior I need to add one further point there um which is that feelings uh are not just valanced they also have particular quality qualities

so that thirst feels different from Hunger feels different from uh Suffocation alarm feels different from sleepiness and so on um and that's because we have multiple homeostats in our bodies um in our brains um the that's because we don't Just have some overarching thing called need need to survive it is it is a compartmentalized in terms of Need for oxygen need for water you need for Sleep need for this need for that and you need to know which need is out of guilter so it's you have to treat each of these needs as categorical variables

forgive me just for a moment going a little bit into math there uh continuous variables are reducible to a common denominator categorical variables are not eight out Of 10 of sleep uh and eight out of 10 of thirst are not the same thing it's not 16 out of 20 of total need as you have to treat them separately you have to both sleep and drink you can't say well I'll reduce my total need by only sleeping I'll skip drinking you know that you'll die if you do that so so these different needs have to be

treated as categorical variables and categorical variables are qualitatively distinctive as I said 8 out of 10 of sleep and8 out Of 10 sleepiness and 8 out of 10 of thirst are qualitatively different so these needs that are broadcast in the form of affect are not only intrinsically balanced in in other words they have an intrinsic goodness and Badness for the organism to the organism but also they have an intrinsic quality they are intrinsically necessarily qualitatively distinctive so why I'm banging on about all of this is I'm trying to show that a mechanistic Account of how

feeling Works um just um naturally gives rise to all of the phenomenal properties um that uh we associate with with with oia which are supposed to be irreducible to mechanistic accounts there are two figures that I think are that should be brought up right now and one I'm just curious the first is Daniel Dennett I wonder if your path has ever crossed with him just because I imagine that he would be very Sympathetic to your research and the role that you think affect plays in Consciousness just because as far as I recall he thinks of

Consciousness as this constellation of many different features of the brain that just sort of coincide together and we sort of mistake them maybe for one magical sort of thing happening in the cartisian theater and then the other figure that I wanted to ask about was Carl friston because I know he's a very important collaborator Of yours among many but your work with him plays a major role in this aspect or dimension of the investigation well um if our our viewers or listeners want to go into that more deepy than I'm going to tell you now

um they should look at um the Journal of Consciousness studies um they had a what they call a symposium although it's not in person it's in writing um about my book uh last year uh yes 2022 um and they invited commentaries from uh Daniel dennet and K friston so you can read their views of my book uh in the Journal of Consciousness studies interestingly uh there was also a com commentary there by Tom Nagel which which which may which may interest some of your your philosophical audience um well you've got a great host of commentators

yes yes there were there were a couple of others too so um um Dan dennet yes he's very sympathetic as as You will see when you read his uh his commentary um but I I I must say there's one point on which he and I disagree or rather I should say there's one point on which I disagree with him um I in my response to his commentary I I I touched on this but um I I haven't spoken to him since then uh so I don't know what what he what his response to my uh

response would be but I drew attention to the fact that um I mean I really don't want to obscure the Fact that he and I were substantially in agreement on you know he was very um positive but just for the sake of of clarity I think that this does need pointing out his view uh is that that Consciousness is an illusion uh you know he speaks of uh the the the user illusion of Consciousness it's a it's a user inter face that um that the cartisian theater I metion yes yes that's it so I'm I

understand exactly I mean you've read my book chapter 10 Deals with this the way in which you know we we're in fact interacting with a virtual reality of that we that we've constructed from the brain's own uh uh ingredients as it were uh and and sort of a Canan picture I'm I'm very uh very um sympathetic with that but when it comes to feelings there's something special about feelings uh you can't ever say uh that you have the illusion that you're in pain or you have the illusion uh that you are depressed I mean you

Just are depressed uh if you if you're depressed you're depressed you might say it's not warranted you might you might say I think that you you you you know you you're in pain but I don't find any problem uh in your uh you know in your peripheral nerve so you shouldn't be in pain and the patient says well I'm sorry doc I am in pain uh that's just because pain is what it is so I just want to make that point is that I think there is Something special about feelings um in that they can't

be elusory they they they they I think when it comes to the outer world and that's other whole story which we probably won't have time to get into but feeling applied to perception I feel like this about that um you know there's that's a different story but I feel like this is just what it is uh it it can't be elusory it is it's because the function of feeling is to tell you you know how how you feel about this the Situation you're in now um Carl friston um Carl friston played a a huge part

part in the my life in the last 10 years it started with um well it progressively in the last 10 years because it started with an article that he wrote um in 2013 um it was called it was in one of the journals of the Royal Society the I forget the title of the journal uh but the the paper had the wonderful title Life as we know it um and uh it was an Attempt by a successful attempt by friston to reduce to a mathematical formulism uh the the causal mechanism of homeostasis that that's basically

what Life as we know it refers to the fact I was referring to earlier you know that how fundamental uh homeostasis is to life uh and he reduced in a set of equations he reduced homeostasis to mechanistic causal laws just like anything else in nature that's not surprising homeostasis is not Complicated you know it's a pretty simple thing that you these are your viable bonds uh if you're moving out of your viable bonds you got to get back into your viable bounds uh priston uh added that that means you have to have a model of

of of yourself in the world you have to have a model of how the world works so that you can predict if I do this it will have those sensory con consquences that's why you it's a it's a it's a model of intentionality actually That why we why we do what we do um it's not random it's designed to bring us back into homeostasis so you have to have a model um a causal model in other words a predictive model um of what what what what consequences will flow from what actions given my model of

the causal relations U um uh of of of things outside of myself um and uh so he made this he made this little set of equations showing how this is our homeostasis works that there's a there's A deviation from a prior preference Point uh that this um this releases action based in the predictive model uh which then brings about a sensory response and then there's a measurement of the gap between the sensory response that was expected and the sensory response that actually flows from your action uh and that's called an error signal and that error

signal is used to update the predictive model so it learns from its actions that's basically what He showed in in that article now you can imagine my excitement because I had reached the conclusion that that Consciousness is at bottom raw feeling uh and that feeling is at bottom an extended form of homeostasis and now here's this article which reduces homeostasis to you know mathematical formalisms and I thought oh my God you know if you can do that of course it must be possible to write equivalent equations for this extended form of Homeostasis that gives rise

to feeling so that was um although he and I had had had several conversations about affect before because uh I I was um you know he works within a tradition of computational Neuroscience computational neuroscientists when I first met priston W talking about feelings um you know that's not their thing um so this culminated our our interactions culminated in US writing a paper together which did just what I said a Moment ago we we we we developed an an extension of his original formalisms to account for for um for feeling and in this way um you

know it's like a culmination of what I was saying earlier about Charmers when I was saying that you can do normal science here you can you can even do um you know mathematical quantitative mechanistic uh reductive science about feeling and so that paper he and I published in 2018 um was called how and why Consciousness arises and in a sense my book um The Hidden Spring uh which came out three years later was just unpacking the the arguments that he and I worked out together in 2018 just unpacking them in Greater detail well one final

question on which to end returning to the hard problem of Consciousness and where I mean where I think the heart of the philosophical Debate lies is granting for the moment that these neurological structures so the reticular activating system of the brain stem the cortex do the things that you or other scientists say they do carry signals and so forth represent colors in the world how mechanically does this at all produce the subjective sense of feeling or the qualia you used the word intrinsic earlier and maybe we could just unpack what that intrinsic means a bit

more or maybe it's just not Reducible any further it just is but I think that's a nice way on which to end sure let me Begin by saying that I think the sense of um puzzlement that comes with the hard problem uh would never have Arisen had we started addressing the question um of the uh physical basis of consciousness by looking at Raw feeling uh I think it's only because we started in the wrong place uh with a function that isn't intrinsically conscious that we became puzzled about Well why is this thing conscious because it

doesn't seem to need to be conscious its mechanism doesn't demand it or explain it uh so had we started with raw feing I don't think anybody would ever have formulated the problem I think the problem uh just doesn't arise know why why does the mechanism that generates feeling feel like something you just say duh what do you mean you know of course the mechanism of feeling feels like something um I want to also add uh for The sake of clarity that my metaphysical position and I think anybody working in neuros pychology has to have a

metaphysical position on the my body problem because it is you a metaphysical problem and my metaphysical position is that of a dual aspect monus so I don't think that the physiological goings on in the brain produce uh the conscious experience in the same way that the liver produces bile I don't think Consciousness is excreted by neurons I Think that there's an underlying mechanism uh that's the monist mechanism uh which uh explains uh the two sets of observable data the objective perspective on the behavior of the brain and the subjective perspective on the being of that

same thing uh so I I I I think that these are two different ways in which we uh can um observe two different observational perspectives upon one and the same mechanism so it's crucial to uh to to answering your Question that you understand what I mean by intrinsic I mean that this is a mechanism described uh in the language of mathematics uh in Galileo wonderfully said the book of nature is written in the language of mathematics and uh it's it's I emphasize that it's an this abstract language it's not a physiological language or a psychological

language it's an abstract it's a language of the that that in which you can articulate the laws that That that govern both sets of observables you need one set of laws that govern both sets of observers and so what I've been trying to articulate in the Hidden Spring is the mechanism the causal mechanis the lawful causal mechanism that generates a that that gives rise to A system that has to monitor its own State uh in the ways that I've just described it's a self-organizing system that is to say it's a homeostatic system that is acting

Uh in in intentionally in order to achieve uh desired outcomes uh it's a self-organizing system which distinguishes itself from its environment because it has to otherwise you can't function homeostatically you need to sequester yourself from the environment in order to maintain your existence separately from the environment you can't just equalize with the environment you have to maintain for example your body temperature not Equalize with the one outside Etc so it's a self-organizing system which is monitoring its own States uh in in in matters that are existentially consequential for the system uh and those states are

just intrinsically veence they they just necessarily are good or bad for the system and they must be categorical variables because we have multiple needs of that existential kind uh and uh when you describe such a system you have just described a system That feels like something if you allow yourself take the Viewpoint of the system that's a absolutely fundamental Point um I think that that's the Rubicon we have to cross and I'm glad we started our conversation in the way that we did because I said uh what frustrated me about the Neuroscience of the 1980s

that I was trained in was that we only treat the brain as an object we don't treat it as a subject it we thereby leave out not only half the picture but the most Interesting half of the picture so if you allow yourself uh as a scientist uh to accept that there is such a thing as the point of view of the system then some systems feel like something and some systems do not um and systems that feel like something have the Dynamics that I've just described that's what I mean by the intrinsic mechanism of

of feeling well a final word about your book so consciousness is such a talked about topic that it's virtually Impossible to do something new and interesting in the area at least from my perspective but the Hidden Spring is really just undoubtedly an exception I mean there's there's no fluff it's rigorous uh there are really countless new and interesting threads and I think our conversation really demonstrates that so thanks so much for writing this book and thanks even more for talking about it with me thanks very much I don't know why anybody talks about any Other

topic than brand mechanisms of Consciousness but thank you very much Robinson I've enjoyed our conversation and also thanks for those kind remarks you [Music] made for NE for [Music]