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This is a crude web presentation of the talk I gave at the University of Wisconsin Thursday noon Genetics Seminar series on April 28th, 2011. I’ve passed on the text I lectured from virtually untouched, inserting the slides shown...there may be some rough spots.
Evolving and Constructing the “I”
• Laboratory of Molecular Biology and Dept. of Zoology University of Wisconsin, Madison WI., USA
- The title of this talk is pretentious - Anyone talking about minds should be mistrusted. Take everything I say with a grain of salt.
Summary of talk:
I. Evolving brains.
The Beast Within
Varieties of “I”
II. Developing brains
III. Modeling the subjective self:
The illusion of agency
The virtual machine and virtual organs
Emotions as evolved organs of consciousness
IV. Embodied cognition
Art and Music
V. Summary - the Self Illusion
Here are the topics. I think of these as skipping, hopefully lightly, through a series of bon-bons. If you were feeling less charitable, you could call it everything but the kitchen sink. In my snowbird nest in Florida over the past few months I wrote down a few things I thought might be interesting, and when I started to realistically time it early last week it was obviously at least two hours long, after 10 years of my retirement philosopause I’ve obviously lost the 50 min. lecture conditioning. But I've been hacking away and promise to be on time today. Section II is down to all of 3 minutes.
Thinking about the "I" between our ears has to start with at least a nod to how it evolved and how it develops.
We have Rube Goldberg brains, like our querty keyboards, parts built by co-opting earlier versions in defiance of what might be best engineering practice - they don’t get off the ground during development without extensive crafting by the physical and social environment.
So...before we plunge into 'how it might work' we need to do just a bit on what happens on evolutionary and developmental time scales, (Topics I and II on the outline). After evolving and developing, we can move on to experiments and ideas on how it works in the present (Topics III, IV, and V).
[Summary Slide, Evolving Brains - The Beast Within]
Here’s cartoon summary, a brief fable, that gets us from single cells to vertebrates in one fell swoop. A single cell or a human has the fundamental question "Now, what do I do next."
Bacterial chemotaxis is an early answer, membrane receptors reporting good stuff or bad stuff and effectors like cilia to respond, along with membrane voltage changes.
Still in unicellular organisms, the invention of sex, mating types, sensing each other's pheromones.
Then, crosstalk between the parts of radially symmetrical invertebrates mediated by diffusible hormones, which became the neurotransmitter used by synapses for more rapid communication between emitter cells and target cells.
In our development and in our brains action is usually antecedent to sensing (acting, analysis, sensing, in slide), embryos start twitching before much sensing is happening, so that the point of sensing is to answer the 'what the did I just do' question.
Moving on to our more direct antecedents.....Brains like this frog brain, less than a gram, maybe 2 cm long are the precursors to the bulges at the top of our spinal cord.
There is a present centered proto-self here, regulating breathing, swallowing, body temperature, heart beat, visual tracking, hearing, etc- interactions with the physical world elemental to having a self, renewed in each instant, constantly tracking and renewing body-environment interactions.
It is a kind of "being" - internal states mapping homeostatic reflexes, drives, motivations, feeding, fighting, fleeing, and fornicating, with these states presumably unknown (in the sense of their being a feeling of what happens) to the beast producing them.
These reflexes, instincts, and drives are supplemented in simple mammalian brains like the rat brain shown here on the left, about 6 grams, by a new kind of cortex supporting more flexible learned behaviors, cortex that is elaborated between the brain stem and the outer layer of the cortex shown here,
Our subsequent version of this simple mammalian brain is usually referred to as the limbic system (the pink portion of our brain shown in the figure).
The mammalian limbic brain offers a more extended consciousness or self, with striking new behaviors, - nurturing and defending the newborn- an expanded range of emotional behaviors- vocal and olfactory communication between mother, offspring, and siblings - learning and memory capabilities way beyond cold blooded vertebrates - remembering food or predator locations,
But there is no hint that they can recall or re-present a situation to reflect on it, either individually or collectively.
As mammals develop more complex social groups and communication, the top layer of the neocortex that covers both the limbic system and the brain stem becomes much larger [slide with three brains]. Brain size correlates with group size. You can see how the smooth cortical surface of the rat brain expands in area and becomes tucked and folded.
The neocortex of primates takes frontal growth and folding to an extreme, with prefrontal cortex being central in our advanced strategic capabilities.
The pop psychology triune brain model - that our show is being run by semi-autonomous parallel reptilian, primitive mammalian, and more advanced neocortical brains doesn't really wash, because the newer stuff very thoroughly projects down into, and regulates all the older structures, through to the brain stem.
[Summary slide, I. Evolving brains - Mirroring]
What you get in terrestrial vertebrates and particularly mammals increasingly sophisticated systems of neurons that mirror the actions and emotions of conspecifics, in rats and in humans you can measure, during observations of another animals purposeful actions or emotions, activity in the nerve cells (dubbed mirror neurons) that would become active if they were carrying out the task themselves.
The common assumption is that these systems have to be a basic substrate for building empathy, a building block for social cognition and eventually the first-person perspective, the idea being that our selves are constructed by mirroring, then internalizing the selves of others. We become ourselves by first becoming those around us.
Our sense of "I" can be described as having several nested components that originate at different times in evolution.
First is the phenomenal animal substrate "I" looking out on a world with a sense of `just being' that doesn't include explicit self referential awareness of being in that state.
The idea is that animals do not see into a moment, rather they look out from it. Subjectively, the animal brain would always be facing forward, focused not on where the latest shift in viewpoint has come from, but where it is heading. Rather than feeling like an observer or a passenger, and animal would have a feeling of simply being the vehicle, of doing the journey. With respect to the emotions regulating reciprocity and retribution, animals would have the status of being moral patients, not moral agents.
Then mirror self recognition experiments in monkeys, dolphins, and some birds, a more advanced sense of `mineness' , having a self, yet still no evidence that it is reflecting on it, it's history or its future. A cat looking in a mirror sees another cat, a monkey can know that it is looking at itself.
A next stage argued for humans is a vocal, visual gestural mimetic largely pre-linguistic "I" that is able to reflect on itself as well as a past and a future.
Finally there is our "I" that recruits language, both inner and outer dialog, giving us our more grandiose "I" that underlies myth and artistic expression.
Today I'm not going to get into brain structures necessary for consciousness or self referral - internal midline structures are crucial but you can lob off the cerebellum, hippocampus, chunks of the temporal cortices and other parts of the neocortex and still feel a conscious self.
There's a lot of recent interest in neuronal types and arrangement that are distinctive to humans and great apes. I'll mention just one.
Spindle, or Von Economo, neurons are a new type of cell found only in the ape lineage, humans have many more of these cells than apes, they are large, stripped down high performance cells, making fewer connections and relaying information rapidly mainly between the anterior cingulate cortex, and the insular cortex inside the frontal lobes the only two areas where they are found in significant numbers.
The insula is essentially the sensory cortex for our internal body sensations, subjective feelings, sensing what we can of homeostatic regulation, It’s not out there on the top like the primary auditory, visual, and somatosensory cortices that are easy to get at with external electrodes. It is tucked on the inside middle as 5-7 folds of the cortex, it’s active in social emotions like trust, empathy, guilt, embarrassment, moral judgement or revulsion. The anterior cingulate does our emotional response to pain, is active in conflict resolution,
I'll mention this area again later.
[Summary Slide, II. Developing brains - Physical environment]
Now let me flick to the second topic... a brief hop, skip, and a jump, through development. It's interesting that the major growth areas of the human cortex during development are those that have changed the most in the evolutionary expansion from monkey to human brains. So, the idea is that its useful for regions of recent evolutionary expansion to remain less mature at birth to increase the influence of postnatal experience on their development.
Starting from a crude innate template, at lower levels of processing, the line orientation detectors in our primary visual cortices are shaped by by real world stimuli, experiments with cats and monkeys show that they are exposed during a critical period of development to an artificial visual world of mostly horizontal or vertical stimuli the majority of cells in the primary visual area come to fire best with those stimuli in the adult.
At a higher level, during development the brain develops spontaneous brain activity (measured with multi-electrode arrays) that becomes increasingly similar to activity evoked by natural scenes. Just as with the more simple line detectors, this is a wiring of environmentally relevant templates in the brain caused by interaction with the physical environment, as the brain is constructing internal models of its environment.
[Summary Slide, II. Developing brains - Social environment]
At birth our visual brain already have icon detectors wired for the key elements of human faces, we are primed for social signals, interactions with caretakers and peers is required for normal brain development, social deprivations or abuse distort it.
Our selves are constructed by mirroring, then internalizing the selves of others. We become those around us, then later we start to also become what we read.
Brain wiring is moulded by culture, visual figure/surround analysis develops differently in Eastern and Western cultures, its moulded by the skill sets we develop - the brains of pianists, tennis players, and talmudic scholars show elaborations of the appropriate areas.
That’s it, 3 minutes on developing brains.
[Summary Slide, III - Modeling the subjective self: The illusion of agency]
After this quick gloss on evolution and development, what about how the thing works. First, our illusion of agency. [point]
The "I" we all are experiencing right now isn't where much of the most interesting action is. I want give you thumbnail clips of several simple observations that point to the martian inside thats really running the show.
The most simple demonstration comes if I ask each of you to close your eyes, become quiet for a few moments, just breathe, and tell you to have no thoughts, images, or feelings in your head, wait quietly for 3 minutes, and then ask how many of you were able to follow this instruction. The answer would be zero, unless a few of you were experienced meditators.
Well, if you’re running your own show what’s the problem? Thoughts just keep popping up from somewhere, that's the martian inside, a brain that is is generating this stuff in spite of “our” conscious best intentions. This is what it is designed to do, generate stuff, regardless of whether “you” in quotes, want it to or not.
What about action, I pick up this book and think my conscious intention to do that is what causes me to pick it up.... wrong, as shown by this simple experiment done first by Benjamin Libet, which I never get tired of showing...
- the subject is instructed: "Flex your finger to push the button when you feel like it, and tell us where the hand on the rapidly moving clock is when you decide to do that."
The time at which an EEG signal indicating brain activation for movement occurs is set as zero time, the report of awareness of intention to push the button is about 350 msec (0.35 seconds) later, and the actual EKG, the voltage in the finger muscle doing the push, happens about 200 msec later than that.
We are 'late for consciousness', the action had already started. The brain has started on our acting earlier than our consciousness of it.
There is a point to this delay in awareness, while its efficient to get an action underway unconsciously it also useful to become aware of it before its final execution and edit or veto it, if it is perceived to be inappropriate. Even if we don't have free will, we have a "free won't" editor.
This is not so crazy, really, -the consequences of my action are programmed back into the next automatic startup of the next action as an anticipation. This information is presented back to the underground processing that is preparing the next instant of action that we will retroactively `intend.'
Our brain thus works in an expanded present that contains the moments antecedent to our awareness of thoughts and actions and that also persists as their consequences are integrated into the ongoing cycle.
This was about acting, we can use a simple experiment with perception to also illustrate a delay in the time it takes us to be conscious of things that are already going on in our brains
Here the instruction is to push the button in response to a light coming on. The button push occurs about 200 msec after the light comes on. If the instruction is: “slow down your response by the tiniest possible amount,” then approximately 700 msec passes before the button push. There is a quantum jump of 500 msec, waiting for consciousness to develop if a conscious rather than unconscious response is requested.
So, both our perceptions and actions are faster than our consciousness of them.
-What's the point of this half second delay for consciousness? There is one: our unconscious mind can shape what we think we are perceiving out there in the real world.
-We compare the information that comes with our library of images, and frequently assume that the stored image is the correct one.
-if I quickly flash an impossible card, a red ace of spades, on the screen, many of you will report seeing an ace of spades or an ace of hearts
• -faster than consciousness
• -consciousness = ‘free won’t’ editor
• -faster than consciousness
• -conscious perception = what ought to be there
A brief summary then is that both acting and sensing are faster than our awareness of them, permitting editing functions to intervene and shape both our final actions (free won't editor) and perceptions (what ought to be there).
Here’s another neat experiment... not only are you late to experiencing yourself as an agent or a perceiver, you can also put that late self anywhere you like in space.
Yet another hapless undergraduate subject on the left in the dark blue trousers sees his own virtual body (light blue trousers) in 3D through head mounted goggles, standing 2 m in front of him and being stroked synchronously with his. Dark is the actual body, light is the virtual body seen in the head goggles.
This is a multisensory conflict, vision of the virtual image being stroked is telling him something different from the felt touching on his back. In a case like this, vision typically dominates over proprioception and touch, and the subject starts to feel that the virtual body seen in front of him is his own body and he mis-localizes himself to the virtual body, to a position outside their bodily borders. This indicates an amazing plasticity, with spatial unity and bodily self-consciousness being computed from multisensory and cognitive processing of bodily information.
So... our subjective I is late to acting and sensing, it’s an after the fact report, and we can place our subjective bodies outside our actual one... I could continue to show experiments showing how flexible our assignment of agency is, how easy it is to think we are responsible for an action when we are not, and vice versa, or experiments showing how our unconscious emotional brain puts a good or bad label on virtually everything we sense. Is it something to go for or to avoid? Helping with the 'what should I do next?" question I started the evolution chunk with.
[Summary Slide, III - Modeling the subjective self - The virtual machine and virtual organs]
Well, these few fragments on relativity of our selves and our illusion of agency provide a backdrop for moving on to ask ‘what kinds of models do we have for a conscious self.
I think there is a consensus view emerging among many philosophers of mind and cognitive neuroscientists, ...it describes our subjective I as a virtual machine. Thomas Metinzger has done one of the most clear and accessible summaries, and I follow some of his points.
The virtual machine of consciousness
“I” = Complex property of neural correlates of consciousness
Space of attentional agency
A new kind of evolved virtual organ
Support from evolved hardware
What he calls the Ego Tunnel (or PSM) is a complex property of the global neural correlate of consciousness (NCC which could be the subject of many lectures) - what make “Mineness” or “I” possible - a vastly reduced model of what is really 'out there'
- It is a transparent mental image that allows the conscious experience of being a self to emerge. (Transparency is our not seeing the firing of neurons in our brain, only what they represent for us).
- The model at a given moment is transparent because the brain has no chance of discovering that is is a model - it is a higher order representation integrating its information in longer time window than the lower order information processing in smaller time windows.
Our visual perception time window is much larger than the time windows of primary visual processing and so those more rapid underlying processes are completely invisible to it (the same thing as not being able to see the individual frames in a movie reel, because our visual integration time is much longer). It is a metabolically efficient, quick and dirty way of knowing only what our evolution has deemed it necessary for us to know.
- Our ancestors did not need to know that a bear-representation was currently active in their brains or that they were currently attending to an internal state representing a slowly approaching wolf....All they needed to know was “Bear over there!” or “Wolf approaching from the left!”
-In this view, Consciousness is taken to be the space of attentional agency, that set of information currently active in our brains to which we can deliberately direct our high level attention. Low level attention is automatic and can be triggered by entirely unconscious events.
-Metzinger makes the further assertion that consciousness is epistemologically irreducible: one reality, one kind of fact, but two kinds of knowledge: first-person knowledge and third-person knowledge, that never can be conflated.
-There is a long list of ideas on why consciousness evolved, what it is good for, doing goal hierarchies and long-terms plans, enhancement of social coordination, etc.
-Old things in the evolution of consciousness are ultrafast and reliable (like qualities of sensory experience) and transparent. In contrast, abstract conscious thought is not transparent or fast, it is slow and unreliable, experienced as ‘made.’
I like Metzinger's description of consciousness as a as a new kind of virtual organ - unlike the permanent hardware of the liver, kidney, or heart it is always present. Virtual organs form for a certain time when needed (like an immune response, or like desire, courage, anger)...they are a new computational strategy, that makes classes of facts globally available and allows attending, flexible reacting, within context.
[Summary Slide, III. Modeling the subjective self - Emotions as evolved organs of consciousness.]
The fast acting hardware of our autonomic and neuroendocrine emotional chemistries evolved to support the new classes of transient virtual organs.
[Summary Slide, IV. Embodied cognition - Social emotions]
These are the basis of an array of cognitions that include the social mirroring neurons which I mentioned already in section I. They include the neuroendocrine circuits being recruited in transient social emotions, expressions of anger, happiness, disgust, surprise, sadness, and fear.
Paul Ekman first documented that these are universal across cultures.
The core facial muscle groups used in these emotional communications are similar in humans and chimps.
These emotions and their muscles are guarantors of authenticity, across cultures people unconsciously and easily distinguish genuine Duchenne smiles, which automatically recruit muscles around the eye and mouth, from fake smiles, which mainly move only muscles around the mouth.
Keltner and others have documented the slightly more subtle facial and body language of signals of embarrassment, smiling, laughing, teasing, touching, loving, compassion, and awe - all reflecting evolved social repertoires. These involve subtle variations in the contractions of at least 45 different facial muscle in humans, way more than a chimpanze uses.
[Summary Slide, IV. Embodied mind - metaphor]
Emphasizing the basic embodyment of our mind - versus a more brain centric or ‘brain in a vat’ sort of perspective - offers a way to link together core biology and our higher cognition - our capacity to express social emotions, to use symbols, metaphors, analogies, parables, working on a plausible story about how various brain areas became able to perform these functions.
All concepts are physical brain circuits that include linkages to the body. What we can think or understand is shaped by, made possible by, and limited by our bodies, brains, and our embodied interactions in the world.
The idea is that our cognition, up through the most abstract reasoning, depends on and makes use of concrete and "low-level" facilities like the sensorimotor system and the emotions. What our bodies are like and how they function structures the concepts we can use to think.
Muscles, thoughts, and emotions reciprocally link together - we can bias emotions by following neutral instructions to hold the muscles associated with them in a particular configuration, a neutral instruction to hold face muscles in a smile configuration makes it harder to feel angry, holding them in a frown configuration makes it harder to follow an instruction to feel friendly.
You can measure subtle muscle motor activity associated with different classes of thought (future thoughts, slight muscle movement ahead; past thoughts, slight muscle movement back).
Metaphoric operations based on fundamental bodily functions are a basis of language construction.
Logic operations of language have their foundation in muscle action in the world (up, down, sideways, in, out, containing, rotation)
A verticality schema comes out of the tendency we and other animals have to employ an up-down orientation in picking out meaningful structures like other animals. An in-out schema gives rise to container metaphors based on our own bodies' in-out orientation.
We view our minds as containers, thoughts are like physical objects inside them, natural language utterances inside our heads. If you say "part of me doesn't believe he is telling the truth," you are using the convention of talking about mind parts as persons.
Our brains link the literal and the metaphorical by duct-taping metaphors and symbols to whichever pre-existing brain areas have provided the closest fit.
I mentioned earlier the insula areas of our cortices that a central site collecting our subjective feelings about our bodies, sending information on up to prefrontal cortical areas via the spindle neurons. Here’s the picture I showed earlier, this hidden internal lobe of the brain with 5-7 gyri, or folds. Ours is larger than apes or monkeys.
The insula registers gustatory disgust and other kinds of sensory disgust. Humans have developed sophisticated capacities to be disgusted by moral failures. We didn’t evolve a new brain region to handle it. Instead, the insula expanded its portfolio. It does moral disgust, which is why gustatory and moral disgust can feel so viscerally similar.
Piggybacking of new and old stuff happens also in the anterior cingulate, again relatively bigger in humans than apes, that’s involved in the subjective, evaluative response to pain as well as conflict resolution. As humans evolved the ability to be more accurately feeling the pain of others, mirroring their emotional pain, it seems reasonable that the anterior cingulate took it on, so that it “does” both physical and psychic pain.
[repeat summary slide, point to.....]
[Summary Slide, IV. Embodied mind - ART and MUSIC ]
The aesthetic spontaneously arises in all cultures, representational art and music, this invites speculation about its adaptive function, and arguments that the development of higher artistic functions has recruited our embodied mirroring social emotions.
Here, for example, is an argument from one of the guys who discovered mirror neurons and wants to challenge the primacy of conscious cognition to emphasize how esthetic responses also consist of universal embodied simulations of actions and emotions conveyed through visual art. He might consider experiments looking at the activities of different classes of mirror neuron systems while subjects are viewing visual art that engages different kinds of empathetic response, for example to Michelangelo's guy struggling to escape from a block of stone.
Semir Zeki argues that registering the constant and essential characteristics of objects is the primordial function of the visual brain and of art. ... that the modularity, parallel processing and temporal hierarchy in visual perception is reflected in visual aesthetics, Mondrian's lines, Calder's motion mobiles, etc. and Margaret Livingstone has written a nice book on correlations between how our visual brain and different artists handle luminance, color, and contrast information.
Its easy to get into some rather mushy evolutionary psychology, the sorts of landscape pictures preferred by 8-year-olds around the world seem to mirror the types of flat, savannah-like vistas of their paleolithic ancestors, or that the desire of these ancestors to impress potential mates by developing artistic skills is the ultimate cause behind Arthur Rubinstein’s saying that “what he really liked in a recital was to fix his eye on some lovely sitting near the stage and imagine he was playing just for her.”
Being a performing classical pianist, I'm much more friendly to arguments that music is an evolutionary adaptation ... and really don't like Pinker's dismissal of music, as he says " auditory cheesecake, an exquisite confection crafted to tickle the sensitive spots of at least six of our mental faculties" ...
Music as an evolutionary adaptation
-Use by other species
-Universality, social bonding and cohesion
-Promoting cognitive development
-Specialized brain structures
-As usual, back to Darwin, proposing a role for music in sexual selection, advertising reproductive fitness to potential mates, other animals do it, birdsong. Whales, frogs, chimpanzees, gibbons, prairie dogs, etc. use musical vocalizations to establish territory, signal predator approach, musical animal calls are analogous to the vocal prosody in our language that adds emotion to the syntax.
-It's universal across cultures, with evidence for musical instruments dating now back to over a 100,000 years ago. ..starting as a communal embodied fusion of musical sounds and body movement, serving social bonding and cohesion, group togetherness and synchrony. Music is better than language for arousing feelings that through mirroring and emotional resonance can bind a group of humans together in joy, love, compassion, anger, or aggression.
Nearly every culture has a genre of music geared towards infants, consistent in how they sound - slow, repetitive and featuring descending pitch contours.
One speculation is that musical meter and the hierarchical organization of pitch are cognitive developments that enabled pre-human ancestors to start up speech communication by refining the fine muscle control required to either vocal or gestural signed speech.
Finally, specific brain lesions as well as brain imaging suggest specialized structures for music - you can dissociate rhythm, metrical extraction, melody outline and analysis. Dedicated memory systems for music can sometimes remain intact after other declarative or episodic memory systems fail.
Pleasing music ramps up the reward circuitry in our brain, just like food, sex, and drugs. Anticipation of the musical high activates the caudate relatively more, and during experiencing the high with chills the nucleus accumbens turns on more..... this is going with the release of feel good dopamine.
V. Summary - the self illusion
So, what is a take on all of these everything but the kitchen sink chunks of information I've been cruising through. In one part of this talk I’ve made the point (point to illusion of agency) that we are this alien, almost Martian, machinery that is actually running our show at the same time we can experience being its emotionally rich product that generates language, metaphor, art, music. The virtual machine model and the idea of transient organs of emotions
These are evolved capabilities supported by evolved hardware, with the “I” that is doing this being a virtual machine, a veneer of illusion that imagines itself to be running the show, sort of like the instrument panels of your car taking themselves to be the driver.
Accepting the evidence that the "I" illusion of our subjective self is a virtual model can feel disconcerting, can have a sort of an arid or 'dry' feel. But, not to worry, these self models or illusions piled on top of apparent mental causation obviously work just fine as the building blocks of our psychology, social life, art and music. They are what makes us a dominant, possibly transient, species on the planet.
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