June 29, 2025 • 22 mins
Exploring Consciousness and How It Happens
Friederike Fabritius welcomes Professor Mark Solms, author of “The Hidden Spring,” for a discussion to answer this, and more. Mark explains the role of the reticular activating system (RAS) in generating human consciousness. It is a structure in the oldest part of our brain, the brainstem, and it plays an important role in consciousness, as well as our emotional state. Solms dives into how the RAS is not just a power source for wakefulness, but a generator of the raw feelings that form the essence of consciousness and how we experience the world.Key distinctions are made between human and animal consciousness, while practical advice on living a fulfilling life by prioritizing emotional well-being over cognitive achievements is also shared. This episode will be sure to leave you thinking about what it really means to be “awake” and the importance of feeling in your everyday life.
00:00 Introduction
00:43 Mark Solms’ Journey into Neuroscience
02:33 Understanding the Reticular Activating System
08:38 Differences in Consciousness Between Animals and Humans
19:33 Implications for Everyday Life
22:41 Conclusion and Final Thoughts
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Professor Mark Solms is Director of Neuropsychology at the Neuroscience Institute of the University of Cape Town. He is also Honorary Lecturer in Neurosurgery at the St Bartholomew’s & Royal London Hospital School of Medicine and an Honorary Fellow of the American College of Psychiatrists. He is a member of the British Psychoanalytical Society and the American and South African Psychoanalytic Associations. He has received numerous honours and awards, including the Sigourney Prize. He has published 350 scientific papers, and eight books, the latest being The Hidden Spring (Norton, 2021). He is the authorized editor and translator of the Revised Standard Edition of the Complete Psychological Works of Sigmund Freud (24 volumes) and the forthcoming Complete Neuroscientific Works of Sigmund Freud (4 volumes).
Mark as Played
Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Friederike Fabritius (00:04):
Hello everyone.
Welcome back to the show today.
I'm with Professor Mark Solms.
He's the author of a book called TheHidden Spring, and if you're the slightest
interested in the human brain and howthe brain operates in the newest thinking
around it, I think you should read it.
I have read it not once, but twice,and I know I'm gonna read it again,
(00:26):
and the next time I read it I'm goingto find new things because it's one
of those books that you read and thenyou think you have understood it,
but then you read it again and thenyou discover new interesting things.
So I'm very honored and happy towelcome you to the show, Mark.
Mark Solms (00:40):
Thank you.
I'm very pleased to be here.
Friederike Fabritius (00:43):
So let me ask you, you have so many unique and novel
and quite almost controversial ideas inyour book about the brain, so I wanna
hear a little bit about you as a person.
What got you interested intothe brain and all these wild
topics such as consciousness andpredictive processing theory?
Mark Solms (01:03):
In retrospect, I believe it was due to a, a, a, a sort of a
tragedy that occurred in my childhood.
Um, when, when my brother fellfrom the roof of a building onto
his head, fractured his skulland sustained a brain hemorrhage.
He was flown to the nearest citywhere he, where he had surgery and,
(01:26):
you know, was to all intents andpurposes, uh, you know, a success.
But when he came back, although hestill looked the same, you know,
this clearly was my brother namedLee, uh, he wasn't the same person.
He had changed, uh, literally hispersonality, his mind was not the same.
(01:46):
And, uh, you know, youmust remember I was a kid.
So, you know, it wasreally , quite, uh, bewildering.
You know, how, how, where's mybrother and who's this guy and how
come, you know this guy is occupyingmy brother's body, you know?
And, uh, so I was, I was, um, broughtface to face at a, at an early
age, with the fact that somehowwe, ourselves, our minds, our, our
(02:13):
persons, are also a bodily organ.
So I, I was sort of compelled to,to try to get my head around this.
And as I said, it wasn't then andthere as a little child that I
decided I'll study neuroscience,but I think that's where it began.
Yeah.
Friederike Fabritius (02:31):
Yeah.
Very interesting.
So I would like to start with you todayon understanding how arousal influences
the brain, the ascending reticularactivating system, because it's something
that I believe we don't hear much about.
When I read the news, it's always aboutdopamine or the prefrontal cortex or the
(02:53):
amygdala, but we hear a little about it.
So could you maybe start out bytelling us what it is and why
it influences our everyday life?
Mark Solms (03:04):
Yes, gladly.
Um, because as you say, it doesn'tget the airtime it deserves.
I'm, I'm, uh, verypleased to talk about it.
As the name suggests, you know,ascending reticular activating
system, it activates our brains.
Literally activates us intowakefulness, into consciousness.
(03:28):
It was thought until this part ofthe brain, uh, was discovered, which
was in 1949, a very long time ago.
Mm-hmm.
Prior to that, it was not unreasonablyassumed, you know, that consciousness
flows in with perception, because ifyou look at your conscious experience
(03:49):
right now, uh, what, what is it?
What does it consist in?
Assuming you have, uh, all of yoursenses, you know, it consists in mm-hmm
vision, uh, and hearing and sematicsensation, you know, the feeling of, of
your body and it's seated in the chair.
Um, and then, and then taste and smell.
These are the raw ingredients ofconsciousness and this is what we are
(04:11):
experiencing, the qualities of perception.
Um, so the, we know that all ofthe sense organs project, uh, they
send information to the cortex.
And this is where those, uh, sensationsI've, I've just, uh, enumerated.
This is where they generated.
Uh, nothing could be more obvious.
(04:33):
Uh, so it was a complete shock when in,uh, 1949, two American physiologists,
Moruzzi and Magoon, learned by, uh,means of, uh, a surgical experimentation
on cats that if you damage a very smallpart of the brain, which they then name
(04:54):
the reticular activating system mm-hmm.
Uh, which is embedded deep within thebrain, not connected to the outside world.
It's in a very primitive part of thebrain, in the brain stem, ancient,
ancient structure share with allvertebrates, that if you damage those
primitive nuclei, it causes a coma.
(05:16):
And not only in cats, in any creatureendowed with this structure, if
that, if that area is damaged,uh, then the lights go out.
In fact, the smallest area of damage inthe human brain that reliably produces
coma is just two cubic millimeters.
In other words, the size of a match head,uh, in the parabrachial complex, which is
(05:39):
part of the reticular activating system.
So damage anywhere within thatsystem can cause coma and does.
But the smallest possiblearea that can cause coma is in
that part of that structure.
And it's, it's remarkably small.
So it's clear that this is what,uh, generates consciousness,
because if you damage this,that's how you lose consciousness.
(06:03):
And we learned, uh, in subsequentyears that this is the part of
the brain that literally wakesyou up and puts you to sleep.
Mm-hmm.
And, and what Moruzzi and Magoon foundis if you sever, if you, if you cut
the ascending fibers from the reticularactivating system ascending up into
the fore brain with its cortex, if youdisconnect the cortex from this part
(06:26):
of the brain stem, then the cortexno longer functions consciously.
So what that demonstrates is thatit is the reticular activating
system that activates that,that that renders conscience.
The functions of the cortex,which are otherwise unconscious.
So the cortex is notintrinsically conscious tissue.
(06:47):
It's the reticular activatingsystem that, uh, um, arouses
the cortex into consciousness.
Now, you might have well asked, well,if this was discovered in 1949, you
know, why do we all think of the cortexas the seat of, of consciousness?
And the reason is because Moruzziand Magoon, in order to explain
(07:08):
their totally unexpected findings,they drew a distinction between
two aspects of consciousness.
They said the cortex, as we had alwaysbelieved, is where the contents and
qualities of consciousness are generated.
But the reticular activatingsystem is a kind of power supply.
(07:29):
Uh, it, it generates a kind of a kindof prerequisite level of arousal.
Uh, so the, the analogy that's used toexplain this, it's a television set.
All the televisual stuff, youknow, the qualities of the sound
and the sight of television,uh, and the programming content.
(07:49):
Uh, it, it's, it's all generated in thetelevision set, but unless you plug it in
at the wall at a power source, you can't,you know, it, it can't do its thing.
So they, they thought of the reticularactivating system as if it were a power
source, as if it were just, mm-hmm.
Just, uh, like necessaryto boot up the, the cortex.
(08:10):
And then the cortex actually produces thequality and the content of consciousness.
Now that, uh, this is where my own workcomes in, and not only my own mm-hmm.
My, my closest colleagues, uh,we, we are all of the view that
this is wrong, this is not true.
Uh, the, the reticular activatingsystem doesn't just supply a
(08:31):
a, a kind of blank wakefulness.
It does generate actual quality andcontent of consciousness itself.
Friederike Fabritius (08:38):
So, I don't wanna interrupt your thought process, but I
have a couple of questions right awayso that I wanna bring in, in the middle,
and then you can go on, because I wasjust asking myself, so does this mean
that animals have a consciousness?
Because so many people think, I mean,I mean, I've always been an animal
lover, so I wanna hear from you now,like cats and dogs and mice and rabbits.
(09:02):
Do you personally think that, becauseif we share that part of the brain, even
if they don't have a very well developedprefrontal cortex or anything like
that, would you say they all have thesame or similar level of consciousness?
Mark Solms (09:16):
Uh, let me preface my answer by saying that, we don't all have
the same complexity of consciousness.
Human beings clearly have, um,aspects of consciousness, which,
which are not shared by other animals.
And this is due largely to language.
(09:36):
Mm-hmm.
Language enables us to abstractourselves from our experience and,
and have these concepts that weuse to think about our experience.
But if your question is, uh, doother animals have experience?
Then the answer is justan unequivocal yes.
Um, all mammals, all, well,certainly all primates, uh, all
(09:59):
mammals, but even all vertebrates.
In other words, that meanscreatures as, uh, supposedly
lowly as, um, snakes and fishes.
Mm-hmm.
And, you know, lizards and so on.
They all have a reticularactivating system.
This part of the brain that I was justtalking about, and what is more, if
(10:21):
you damage that structure in thoseanimals, they too go into coma.
So it has the same function in allanimals, but remember the, the, the
general prejudice is that, well, all thisdoes is switches on lights, you know?
Yeah.
If you don't have any cortex to be litup, as fishs and, and, uh, and, and
reptiles and so on, don't have then, youknow, the assumption would be, well then,
(10:45):
you know, they have this arousal, butthere's no content or quality to their
consciousness because there's no cortex.
And, and that's exactly, uh, where, whereI left off before your question when
I was saying that that view is wrong.
The evidence for it, since youare asking me about animals, let
me start with animal evidence.
Friederike Fabritius (11:05):
Yeah, please.
Um,
Mark Solms (11:06):
if you remove the cortex from a young mammal, which has
sadly been done many, many times.
So by young mammal, I meana cat or a dog or a rodent.
If you remove their cortex shortlyafter birth you, you, you might think
on the basis of what Moruzzi and Magoontaught us, you might think, well, they,
(11:28):
there will be nothing it's like to bethem because there's no cortex there.
So there will be no qualityor content to the experience.
But that's not what happens.
They are fully conscious in thesense that they go to sleep, at night
and they wake up in the morning.
Uh, but more than that, theyare emotionally responsive.
(11:48):
In other words, if youfrighten them, they run away.
If you tickle them, they enjoy it.
If you, uh, uh, um, frustrate them,they become angry and aggressive.
They copulate, they evennurture their young.
Uh, not perfectly, but they do it.
You know, so they show all thebasic emotions, uh, that you would
(12:08):
expect in, in this situationsin which you would expect them.
Now moving on from animals, thesame applies to human beings.
Of course, you can't surgically removethe cortex from a human being for
experimental purposes, but sadly, thereare diseases, the one I'm going to refer
to is called hydranencephaly, uh, whichis where the child is born with no cortex.
(12:32):
So they have a perfectly functionalbrainstem, but no cortex, if in
other words, they have on Moruzzi andMagoon's theory, they have a power
supply, but nothing for it to boot up.
So on that theory, these children shouldbe, if not in a coma, they, they should
at least be what we call vegetative.
The vegetative state is, is alsoknown as non-responsive wakefulness.
(12:58):
In other words, there shouldbe a kind of blank wakefulness.
The sleep waking cycleis an autonomic reflex.
So, you know, they should wake up andgo to sleep, but they shouldn't respond.
They shouldn't beinteracting with their world.
And that's not what happens.
Uh, these children, not only do theyhave a sleep wake cycle, but when they're
(13:19):
awake, they are emotionally responsive.
Uh, so if you clap yourhands, they startle.
You know, if you tickle them, they giggle.
Uh, if you take away somethingthat they have in their mouths and
are, are enjoying, they, they fussand they fret and they protest.
So there's clear emotional responsivity.
(13:39):
Now, the thing I need to emphasize in whatI'm saying is it's emotional responsivity.
Friederike Fabritius (13:44):
Mm-hmm.
Mark Solms (13:44):
It's impossible for these kids to see consciously 'cause they've got
no cortex, they can't hear consciously.
But all of that information from our senseorgans doesn't only go to the cortex,
it also goes to the brainstem where it'sprocessed unconsciously in the sense that
the visual information is not consciouslyrepresented, but it has an effect.
(14:08):
And that effect is on theemotional state of the child.
So the child responds to thestimuli, but the only thing that
it's aware of is the feeling.
It doesn't know why, it'sfeeling what it's feeling, but
it just shows the feelings.
Many of my neuroscientific colleagues whenI present this evidence to them and say,
you, you, you know, the theory is wrongbecause look, these kids do have a quality
(14:31):
and a content to their consciousness.
It's just that that quality and contentis emotional rather than perceptual.
Friederike Fabritius (14:38):
Mm-hmm.
Mark Solms (14:38):
They say, well, how do you know that the child
is actually feeling anything?
These might just be instinctual,you know, stereotypes.
And, first of all, I would invite themto actually interact with these kids.
, It's very hard to sustain the beliefthat these are just reflexes, but
the kids can't report on what they'reexperiencing 'cause they don't have
(14:59):
cortex and they don't have language.
So, you know, you've gotta find a wayaround that radical, skeptical argument.
And, uh, the way around it is to takehuman beings who do have cortex and
stimulate the reticular activating system.
And what would you expect if all thatit did was provide a, a power supply?
(15:22):
Maybe it would makeyou more or less alert.
You know, it's the kind ofthing an anesthetist would feel.
Friederike Fabritius (15:28):
Mm-hmm.
Mark Solms (15:28):
But that's not what happens.
If you stimulate, as we have occasionto do clinically, for example,
when you implant an electrode for apatient, uh, with Parkinson's disease,
the area that you're stimulatingis just a few millimeters away from
the reticular activating system.
And on occasion, the electrodegoes a little too deep.
And what we find is intenseemotional responses.
(15:51):
But now these patients can, can speak.
So they say, you know, there, there'sa famous case reported by Blomstedt
where the patient fell into a suicidaldepression within five seconds of
the stimulator being switched on,and, um, that stimulator went into
something called the substantial nigra.
But that's just one of the many structuresin the reticular activating system.
(16:15):
If you stimulate anywhere in the reticularactivating system or a structure right
next to it called the periaqueductalgray, you get the most intense emotional
responses and the widest variety ofemotional responses anywhere in the brain.
And these are patients whocan report what they feel.
Friederike Fabritius (16:33):
Right.
Mark Solms (16:34):
There's other evidence too, if you put a, a person in an
intense emotional state, um, say fearor sadness or rage or happiness, uh,
into a positron emission tomogram, youknow, a functional imaging scanner, what
you see, where the activation is thatcorresponds to that intense emotional,
(16:54):
raw feeling state, and the activationis in the reticular activating system.
Again, it's in the brainstem.
And, and, and one last point.
Which is, uh, you mentioneddopamine a moment ago.
Friederike Fabritius (17:06):
Mm-hmm.
Mark Solms (17:07):
Dopamine is of course one of the, uh, neurotransmitters
that we target in the treatment ofpsychiatric patients with psychosis.
Anti-psychotics block dopamine.
If you boost dopamine, youproduce a manic state of mind.
Antidepressants, they,they increase serotonin.
Um, some anxiety drugs,they suppress noradrenaline.
(17:30):
These brain chemicals that I've justmentioned, they all have their source
cells in the reticular activating system.
People don't realize this, butdopamine, serotonin, noradrenaline,
they all are sourced in thereticular activating system.
And as I've just been saying, if youmanipulate those neurotransmitters,
(17:51):
you don't manipulate thelevel of consciousness you
manipulate its emotional quality.
That's what psycho-pharmacology is for.
So all of these different lines ofevidence converge on the inescapable
conclusion that the reticularactivating system, which everybody
agrees, is prerequisite for any formof consciousness that the reticular
(18:14):
activating system doesn't justgenerate a kind of volume control.
It generates qualities of consciousness,which we call raw feeling.
Which means that the basic form ofconsciousness, remember it's prerequisite
for any other form, the basic formof consciousness is raw feeling.
(18:36):
What we technically call affect.
Affect is the basic form of consciousness.
And this is what the reticularactivating system generates.
Friederike Fabritius (18:45):
I think that is, not crazy in the crazy sense, but
if I think about it, when I studiedneuropsychology maybe 20 years ago,
the brainstem was mentioned for maybetwo millisecond in the whole thing.
You know, we never talked about it.
And I think we discoverso many new functions.
(19:05):
I, I think, not in this episode, butmaybe in another, I have recently
rediscovered the cerebellum as doing muchmore than what we thought it was doing.
Or we have the galia cellsand they do so much more than
we thought they, they would.
So I think we should really stayopen-minded and understand that
what we thought was true doesn'thave to be true when you have new
(19:29):
findings or somebody who just looksat the finding through a new lens.
Before we sign off for thisepisode, I have a question to you.
I'm always trying to findlike applicable things.
So is there something we can dowith our ascending reticulate,
our reticula activating systemthat we can use for everyday life?
(19:50):
Because it seems to bevery relevant for emotions.
I think it's also kind ofinfluencing what we pay attention
to and how we perceive the world.
So I just wonder are there any, apartfrom understanding that it does so much
more than we thought it does regardingconsciousness and our affection, is there
(20:12):
anything you, for example, do for your RASsystem or anything people could do to keep
it in good shape or anything applicablewhere you would say, you know, I always do
this little thing, it helps my RAS systemstay in shape, or something like that?
Mark Solms (20:28):
Um, I think that, so you're speaking about, hygiene, you
know, what, what we could do froma sort of lifestyle point of view.
So I'll just mention, first of allsomething along those lines and then
come to what I think is probably themain thing, the main take home message
for, you know, what does this mean forus in terms of how we live our lives.
From the, a lifestyle point of view,you know, there are things like,
(20:52):
stimulants that we take all the time.
When I say stimulants, I mean things asbasic as coffee, you know, and, and so on.
What we don't realize is thatthese things are acting on the
reticular activating system.
That's why they alert us and,you know, or the opposite.
But I think the take home messagereally is that if the most basic
(21:14):
for, for, first of all, what arewe, if not our consciousness?
You know, I mean, if I couldn't experiencemy being alive, there wouldn't be
much point to being alive, you know?
So consciousness is what we are.
To realize as these findings clearlydemonstrate that the basic nature
of consciousness is feeling then Ithink that the take home message is,
(21:38):
well, that's what it's all about.
Consciousness is about feeling.
And this is what we should orientateour lives around and awareness that
everything we do is really for the sakeof feeling good, feeling better, you
know , as opposed to feeling bad, feelinglow, feeling anxious, feeling despondent.
(21:59):
Everything that we are doing is totry and make ourselves feel happier,
feel more, um, fulfilled, feel morethat life has meaning and so on.
And all of this is about feeling.
So I think that we should downgrade ouremphasis on intelligence and cognition.
And remember that it's alljust in the service of feeling.
(22:20):
Feeling is is at the heart of the matter.
Friederike Fabritius (22:23):
Yeah.
And that's very interesting becauseif you maximize for feelings.
You know, you maximize for a happier life.
So you could be chasing so manythings that if they don't make
you happy, then what's the point?
So thank you so much for sharing thisactionable insight that's so relevant.
Thank you so much for today.
(22:43):
I'll have you back for two moreepisodes, so stay tuned for those.
Thank you so much.
Mark Solms (22:48):
Very good.
Thank you.
Hello everyone.
Welcome back to the show today.
I'm with Professor Mark Solms.
He's the author of a book called TheHidden Spring, and if you're the slightest
interested in the human brain and howthe brain operates in the newest thinking
around it, I think you should read it.
I have read it not once, but twice,and I know I'm gonna read it again,
(00:26):
and the next time I read it I'm goingto find new things because it's one
of those books that you read and thenyou think you have understood it,
but then you read it again and thenyou discover new interesting things.
So I'm very honored and happy towelcome you to the show, Mark.
Mark Solms (00:40):
Thank you.
I'm very pleased to be here.
Friederike Fabritius (00:43):
So let me ask you, you have so many unique and novel
and quite almost controversial ideas inyour book about the brain, so I wanna
hear a little bit about you as a person.
What got you interested intothe brain and all these wild
topics such as consciousness andpredictive processing theory?
Mark Solms (01:03):
In retrospect, I believe it was due to a, a, a, a sort of a
tragedy that occurred in my childhood.
Um, when, when my brother fellfrom the roof of a building onto
his head, fractured his skulland sustained a brain hemorrhage.
He was flown to the nearest citywhere he, where he had surgery and,
(01:26):
you know, was to all intents andpurposes, uh, you know, a success.
But when he came back, although hestill looked the same, you know,
this clearly was my brother namedLee, uh, he wasn't the same person.
He had changed, uh, literally hispersonality, his mind was not the same.
(01:46):
And, uh, you know, youmust remember I was a kid.
So, you know, it wasreally , quite, uh, bewildering.
You know, how, how, where's mybrother and who's this guy and how
come, you know this guy is occupyingmy brother's body, you know?
And, uh, so I was, I was, um, broughtface to face at a, at an early
age, with the fact that somehowwe, ourselves, our minds, our, our
(02:13):
persons, are also a bodily organ.
So I, I was sort of compelled to,to try to get my head around this.
And as I said, it wasn't then andthere as a little child that I
decided I'll study neuroscience,but I think that's where it began.
Yeah.
Friederike Fabritius (02:31):
Yeah.
Very interesting.
So I would like to start with you todayon understanding how arousal influences
the brain, the ascending reticularactivating system, because it's something
that I believe we don't hear much about.
When I read the news, it's always aboutdopamine or the prefrontal cortex or the
(02:53):
amygdala, but we hear a little about it.
So could you maybe start out bytelling us what it is and why
it influences our everyday life?
Mark Solms (03:04):
Yes, gladly.
Um, because as you say, it doesn'tget the airtime it deserves.
I'm, I'm, uh, verypleased to talk about it.
As the name suggests, you know,ascending reticular activating
system, it activates our brains.
Literally activates us intowakefulness, into consciousness.
(03:28):
It was thought until this part ofthe brain, uh, was discovered, which
was in 1949, a very long time ago.
Mm-hmm.
Prior to that, it was not unreasonablyassumed, you know, that consciousness
flows in with perception, because ifyou look at your conscious experience
(03:49):
right now, uh, what, what is it?
What does it consist in?
Assuming you have, uh, all of yoursenses, you know, it consists in mm-hmm
vision, uh, and hearing and sematicsensation, you know, the feeling of, of
your body and it's seated in the chair.
Um, and then, and then taste and smell.
These are the raw ingredients ofconsciousness and this is what we are
(04:11):
experiencing, the qualities of perception.
Um, so the, we know that all ofthe sense organs project, uh, they
send information to the cortex.
And this is where those, uh, sensationsI've, I've just, uh, enumerated.
This is where they generated.
Uh, nothing could be more obvious.
(04:33):
Uh, so it was a complete shock when in,uh, 1949, two American physiologists,
Moruzzi and Magoon, learned by, uh,means of, uh, a surgical experimentation
on cats that if you damage a very smallpart of the brain, which they then name
(04:54):
the reticular activating system mm-hmm.
Uh, which is embedded deep within thebrain, not connected to the outside world.
It's in a very primitive part of thebrain, in the brain stem, ancient,
ancient structure share with allvertebrates, that if you damage those
primitive nuclei, it causes a coma.
(05:16):
And not only in cats, in any creatureendowed with this structure, if
that, if that area is damaged,uh, then the lights go out.
In fact, the smallest area of damage inthe human brain that reliably produces
coma is just two cubic millimeters.
In other words, the size of a match head,uh, in the parabrachial complex, which is
(05:39):
part of the reticular activating system.
So damage anywhere within thatsystem can cause coma and does.
But the smallest possiblearea that can cause coma is in
that part of that structure.
And it's, it's remarkably small.
So it's clear that this is what,uh, generates consciousness,
because if you damage this,that's how you lose consciousness.
(06:03):
And we learned, uh, in subsequentyears that this is the part of
the brain that literally wakesyou up and puts you to sleep.
Mm-hmm.
And, and what Moruzzi and Magoon foundis if you sever, if you, if you cut
the ascending fibers from the reticularactivating system ascending up into
the fore brain with its cortex, if youdisconnect the cortex from this part
(06:26):
of the brain stem, then the cortexno longer functions consciously.
So what that demonstrates is thatit is the reticular activating
system that activates that,that that renders conscience.
The functions of the cortex,which are otherwise unconscious.
So the cortex is notintrinsically conscious tissue.
(06:47):
It's the reticular activatingsystem that, uh, um, arouses
the cortex into consciousness.
Now, you might have well asked, well,if this was discovered in 1949, you
know, why do we all think of the cortexas the seat of, of consciousness?
And the reason is because Moruzziand Magoon, in order to explain
(07:08):
their totally unexpected findings,they drew a distinction between
two aspects of consciousness.
They said the cortex, as we had alwaysbelieved, is where the contents and
qualities of consciousness are generated.
But the reticular activatingsystem is a kind of power supply.
(07:29):
Uh, it, it generates a kind of a kindof prerequisite level of arousal.
Uh, so the, the analogy that's used toexplain this, it's a television set.
All the televisual stuff, youknow, the qualities of the sound
and the sight of television,uh, and the programming content.
(07:49):
Uh, it, it's, it's all generated in thetelevision set, but unless you plug it in
at the wall at a power source, you can't,you know, it, it can't do its thing.
So they, they thought of the reticularactivating system as if it were a power
source, as if it were just, mm-hmm.
Just, uh, like necessaryto boot up the, the cortex.
(08:10):
And then the cortex actually produces thequality and the content of consciousness.
Now that, uh, this is where my own workcomes in, and not only my own mm-hmm.
My, my closest colleagues, uh,we, we are all of the view that
this is wrong, this is not true.
Uh, the, the reticular activatingsystem doesn't just supply a
(08:31):
a, a kind of blank wakefulness.
It does generate actual quality andcontent of consciousness itself.
Friederike Fabritius (08:38):
So, I don't wanna interrupt your thought process, but I
have a couple of questions right awayso that I wanna bring in, in the middle,
and then you can go on, because I wasjust asking myself, so does this mean
that animals have a consciousness?
Because so many people think, I mean,I mean, I've always been an animal
lover, so I wanna hear from you now,like cats and dogs and mice and rabbits.
(09:02):
Do you personally think that, becauseif we share that part of the brain, even
if they don't have a very well developedprefrontal cortex or anything like
that, would you say they all have thesame or similar level of consciousness?
Mark Solms (09:16):
Uh, let me preface my answer by saying that, we don't all have
the same complexity of consciousness.
Human beings clearly have, um,aspects of consciousness, which,
which are not shared by other animals.
And this is due largely to language.
(09:36):
Mm-hmm.
Language enables us to abstractourselves from our experience and,
and have these concepts that weuse to think about our experience.
But if your question is, uh, doother animals have experience?
Then the answer is justan unequivocal yes.
Um, all mammals, all, well,certainly all primates, uh, all
(09:59):
mammals, but even all vertebrates.
In other words, that meanscreatures as, uh, supposedly
lowly as, um, snakes and fishes.
Mm-hmm.
And, you know, lizards and so on.
They all have a reticularactivating system.
This part of the brain that I was justtalking about, and what is more, if
(10:21):
you damage that structure in thoseanimals, they too go into coma.
So it has the same function in allanimals, but remember the, the, the
general prejudice is that, well, all thisdoes is switches on lights, you know?
Yeah.
If you don't have any cortex to be litup, as fishs and, and, uh, and, and
reptiles and so on, don't have then, youknow, the assumption would be, well then,
(10:45):
you know, they have this arousal, butthere's no content or quality to their
consciousness because there's no cortex.
And, and that's exactly, uh, where, whereI left off before your question when
I was saying that that view is wrong.
The evidence for it, since youare asking me about animals, let
me start with animal evidence.
Friederike Fabritius (11:05):
Yeah, please.
Um,
Mark Solms (11:06):
if you remove the cortex from a young mammal, which has
sadly been done many, many times.
So by young mammal, I meana cat or a dog or a rodent.
If you remove their cortex shortlyafter birth you, you, you might think
on the basis of what Moruzzi and Magoontaught us, you might think, well, they,
(11:28):
there will be nothing it's like to bethem because there's no cortex there.
So there will be no qualityor content to the experience.
But that's not what happens.
They are fully conscious in thesense that they go to sleep, at night
and they wake up in the morning.
Uh, but more than that, theyare emotionally responsive.
(11:48):
In other words, if youfrighten them, they run away.
If you tickle them, they enjoy it.
If you, uh, uh, um, frustrate them,they become angry and aggressive.
They copulate, they evennurture their young.
Uh, not perfectly, but they do it.
You know, so they show all thebasic emotions, uh, that you would
(12:08):
expect in, in this situationsin which you would expect them.
Now moving on from animals, thesame applies to human beings.
Of course, you can't surgically removethe cortex from a human being for
experimental purposes, but sadly, thereare diseases, the one I'm going to refer
to is called hydranencephaly, uh, whichis where the child is born with no cortex.
(12:32):
So they have a perfectly functionalbrainstem, but no cortex, if in
other words, they have on Moruzzi andMagoon's theory, they have a power
supply, but nothing for it to boot up.
So on that theory, these children shouldbe, if not in a coma, they, they should
at least be what we call vegetative.
The vegetative state is, is alsoknown as non-responsive wakefulness.
(12:58):
In other words, there shouldbe a kind of blank wakefulness.
The sleep waking cycleis an autonomic reflex.
So, you know, they should wake up andgo to sleep, but they shouldn't respond.
They shouldn't beinteracting with their world.
And that's not what happens.
Uh, these children, not only do theyhave a sleep wake cycle, but when they're
(13:19):
awake, they are emotionally responsive.
Uh, so if you clap yourhands, they startle.
You know, if you tickle them, they giggle.
Uh, if you take away somethingthat they have in their mouths and
are, are enjoying, they, they fussand they fret and they protest.
So there's clear emotional responsivity.
(13:39):
Now, the thing I need to emphasize in whatI'm saying is it's emotional responsivity.
Friederike Fabritius (13:44):
Mm-hmm.
Mark Solms (13:44):
It's impossible for these kids to see consciously 'cause they've got
no cortex, they can't hear consciously.
But all of that information from our senseorgans doesn't only go to the cortex,
it also goes to the brainstem where it'sprocessed unconsciously in the sense that
the visual information is not consciouslyrepresented, but it has an effect.
(14:08):
And that effect is on theemotional state of the child.
So the child responds to thestimuli, but the only thing that
it's aware of is the feeling.
It doesn't know why, it'sfeeling what it's feeling, but
it just shows the feelings.
Many of my neuroscientific colleagues whenI present this evidence to them and say,
you, you, you know, the theory is wrongbecause look, these kids do have a quality
(14:31):
and a content to their consciousness.
It's just that that quality and contentis emotional rather than perceptual.
Friederike Fabritius (14:38):
Mm-hmm.
Mark Solms (14:38):
They say, well, how do you know that the child
is actually feeling anything?
These might just be instinctual,you know, stereotypes.
And, first of all, I would invite themto actually interact with these kids.
, It's very hard to sustain the beliefthat these are just reflexes, but
the kids can't report on what they'reexperiencing 'cause they don't have
(14:59):
cortex and they don't have language.
So, you know, you've gotta find a wayaround that radical, skeptical argument.
And, uh, the way around it is to takehuman beings who do have cortex and
stimulate the reticular activating system.
And what would you expect if all thatit did was provide a, a power supply?
(15:22):
Maybe it would makeyou more or less alert.
You know, it's the kind ofthing an anesthetist would feel.
Friederike Fabritius (15:28):
Mm-hmm.
Mark Solms (15:28):
But that's not what happens.
If you stimulate, as we have occasionto do clinically, for example,
when you implant an electrode for apatient, uh, with Parkinson's disease,
the area that you're stimulatingis just a few millimeters away from
the reticular activating system.
And on occasion, the electrodegoes a little too deep.
And what we find is intenseemotional responses.
(15:51):
But now these patients can, can speak.
So they say, you know, there, there'sa famous case reported by Blomstedt
where the patient fell into a suicidaldepression within five seconds of
the stimulator being switched on,and, um, that stimulator went into
something called the substantial nigra.
But that's just one of the many structuresin the reticular activating system.
(16:15):
If you stimulate anywhere in the reticularactivating system or a structure right
next to it called the periaqueductalgray, you get the most intense emotional
responses and the widest variety ofemotional responses anywhere in the brain.
And these are patients whocan report what they feel.
Friederike Fabritius (16:33):
Right.
Mark Solms (16:34):
There's other evidence too, if you put a, a person in an
intense emotional state, um, say fearor sadness or rage or happiness, uh,
into a positron emission tomogram, youknow, a functional imaging scanner, what
you see, where the activation is thatcorresponds to that intense emotional,
(16:54):
raw feeling state, and the activationis in the reticular activating system.
Again, it's in the brainstem.
And, and, and one last point.
Which is, uh, you mentioneddopamine a moment ago.
Friederike Fabritius (17:06):
Mm-hmm.
Mark Solms (17:07):
Dopamine is of course one of the, uh, neurotransmitters
that we target in the treatment ofpsychiatric patients with psychosis.
Anti-psychotics block dopamine.
If you boost dopamine, youproduce a manic state of mind.
Antidepressants, they,they increase serotonin.
Um, some anxiety drugs,they suppress noradrenaline.
(17:30):
These brain chemicals that I've justmentioned, they all have their source
cells in the reticular activating system.
People don't realize this, butdopamine, serotonin, noradrenaline,
they all are sourced in thereticular activating system.
And as I've just been saying, if youmanipulate those neurotransmitters,
(17:51):
you don't manipulate thelevel of consciousness you
manipulate its emotional quality.
That's what psycho-pharmacology is for.
So all of these different lines ofevidence converge on the inescapable
conclusion that the reticularactivating system, which everybody
agrees, is prerequisite for any formof consciousness that the reticular
(18:14):
activating system doesn't justgenerate a kind of volume control.
It generates qualities of consciousness,which we call raw feeling.
Which means that the basic form ofconsciousness, remember it's prerequisite
for any other form, the basic formof consciousness is raw feeling.
(18:36):
What we technically call affect.
Affect is the basic form of consciousness.
And this is what the reticularactivating system generates.
Friederike Fabritius (18:45):
I think that is, not crazy in the crazy sense, but
if I think about it, when I studiedneuropsychology maybe 20 years ago,
the brainstem was mentioned for maybetwo millisecond in the whole thing.
You know, we never talked about it.
And I think we discoverso many new functions.
(19:05):
I, I think, not in this episode, butmaybe in another, I have recently
rediscovered the cerebellum as doing muchmore than what we thought it was doing.
Or we have the galia cellsand they do so much more than
we thought they, they would.
So I think we should really stayopen-minded and understand that
what we thought was true doesn'thave to be true when you have new
(19:29):
findings or somebody who just looksat the finding through a new lens.
Before we sign off for thisepisode, I have a question to you.
I'm always trying to findlike applicable things.
So is there something we can dowith our ascending reticulate,
our reticula activating systemthat we can use for everyday life?
(19:50):
Because it seems to bevery relevant for emotions.
I think it's also kind ofinfluencing what we pay attention
to and how we perceive the world.
So I just wonder are there any, apartfrom understanding that it does so much
more than we thought it does regardingconsciousness and our affection, is there
(20:12):
anything you, for example, do for your RASsystem or anything people could do to keep
it in good shape or anything applicablewhere you would say, you know, I always do
this little thing, it helps my RAS systemstay in shape, or something like that?
Mark Solms (20:28):
Um, I think that, so you're speaking about, hygiene, you
know, what, what we could do froma sort of lifestyle point of view.
So I'll just mention, first of allsomething along those lines and then
come to what I think is probably themain thing, the main take home message
for, you know, what does this mean forus in terms of how we live our lives.
From the, a lifestyle point of view,you know, there are things like,
(20:52):
stimulants that we take all the time.
When I say stimulants, I mean things asbasic as coffee, you know, and, and so on.
What we don't realize is thatthese things are acting on the
reticular activating system.
That's why they alert us and,you know, or the opposite.
But I think the take home messagereally is that if the most basic
(21:14):
for, for, first of all, what arewe, if not our consciousness?
You know, I mean, if I couldn't experiencemy being alive, there wouldn't be
much point to being alive, you know?
So consciousness is what we are.
To realize as these findings clearlydemonstrate that the basic nature
of consciousness is feeling then Ithink that the take home message is,
(21:38):
well, that's what it's all about.
Consciousness is about feeling.
And this is what we should orientateour lives around and awareness that
everything we do is really for the sakeof feeling good, feeling better, you
know , as opposed to feeling bad, feelinglow, feeling anxious, feeling despondent.
(21:59):
Everything that we are doing is totry and make ourselves feel happier,
feel more, um, fulfilled, feel morethat life has meaning and so on.
And all of this is about feeling.
So I think that we should downgrade ouremphasis on intelligence and cognition.
And remember that it's alljust in the service of feeling.
(22:20):
Feeling is is at the heart of the matter.
Friederike Fabritius (22:23):
Yeah.
And that's very interesting becauseif you maximize for feelings.
You know, you maximize for a happier life.
So you could be chasing so manythings that if they don't make
you happy, then what's the point?
So thank you so much for sharing thisactionable insight that's so relevant.
Thank you so much for today.
(22:43):
I'll have you back for two moreepisodes, so stay tuned for those.
Thank you so much.
Mark Solms (22:48):
Very good.
Thank you.
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