The seven attributes of minimal consciousness

Cover of The Evolution of the Sensitive SoulI’m still working my way through Simona Ginsburg and Eva Jablonka’s tome: The Evolution of the Sensitive Soul.  This is the second post of a series on their book.  I’m actually on the last chapter, but that last chapter is close to a hundred pages long, and the book’s prose is dense.  Light reading it isn’t.

Still, it includes a vast overview of the study of consciousness and the mind, not just in contemporary times, but going back to the 19th century and beyond.  For anyone looking for a broad historical overview of the scientific study of the mind, and is willing to put in some work to parse the prose, it’s worth checking out.

As I noted in the first post, G&J aren’t focusing on human level consciousness, that is, higher order metacognitive self awareness and symbolic thought, the “rational soul.”  Similar to the work by Todd Feinberg and Jon Mallatt, their focus is on minimal consciousness, often called “primary consciousness”.  They equate this minimal consciousness with sentience, the ability to  have subjective experiencing (they prefer “experiencing” to just “experience”), which they relate to Aristotle’s “sensitive soul.”

Even having defined this scope however, there remains lots of room for different interpretations.  In an attempt to more precisely define the target of their investigation, they marshal information from contemporary neurobiology and cognitive scientists, along with their theories, to describe seven attributes of minimal consciousness.

  1. Global activity and accessibility.  It’s widely agreed that consciousness is not localized in narrow brain regions.  Although the core ignition and distribution mechanisms might be localized to particular networks, it involves content widely available from disparate brain regions broadcast or made available to the other specialty processes that otherwise work in isolation.
  2. Binding and unification.  The unified nature of conscious perception, such as experiencing the sight of a dog rather than all the constituent sensory components.  Many theories see this being associated with the synchronized firing of neurons in various brain regions, built with recurrent connections between those regions.
  3. Selection, plasticity, learning, and attention.  We are generally conscious of only one thing at a time, or one group of related things.  This involves competition and selection of the winner with the losers inhibited.  It also involves plasticity, which enables learning.
  4. Intentionality (aboutness).  Conscious states are about something, which may be something in the world or the body.  The notion of mental representation is tightly related to this attribute.
  5. Temporal “thickness”.  Neural processing that is quick and fleeting is not conscious.  To be conscious of something requires that the activity be sustained through recurrent feedback loops, both locally and globally.
  6. Values, emotions, goals.  Experience is felt, that is, it has a valence, a sense of good or bad, pleasure or pain, satisfaction or frustration.  These are the attributes that provide motivations, impetus, to a conscious system, that propel it toward certain “attractor” states and away from others.
  7. Embodiment, agency, and a notion of “self”.  The brain is constantly receiving feedback from the body, providing a constant “buzz”, the feeling of existence.  This gives the system a feeling of bodily self.  (Not to be confused with the notion of metacognitive self in human level consciousness.)

G&J refer to this as “the emergentist consensus.”  It seems to pull ideas from global workspace theory, various recurrent loop theories, Damasio’s theories of self and embodiment, and a host of other sources.

It’s important to note that these attributes aren’t free standing independent things.  They interact with and depend on each other.  For example, for a sensory image to be consciously perceived (4), it must achieve (1) global availability by winning (3) selective attention by (2) binding, which results in (5) temporal thickness and strengthens the plasticity aspect of (3).  This process may trigger a reaction which goes through a similar process to achieve (6) value.  All with (7) as a constant underlying hum, subtly (or not so subtly) stacking the deck of what wins (3).

So that’s G&J’s target.  Their goal is to identify functionality, capabilities which demonstrate these attributes in particular species.  Their focus is on learning capabilities, which I’ll go into in the next post.

What do you think about these attributes?  Do they strike you as necessary and sufficient for minimal consciousness, the “sensitive soul”?  Or are they too much, bringing in inessential mechanisms?

Posted in Mind and AI | Tagged , , , , , , , , | 20 Comments

The Q-Drive and the difficulty of interstellar exploration

I’ve discussed the difficulties of interstellar exploration before.  To get a spacecraft to another star within a human lifetime requires accelerating it to an appreciable percentage of c (the speed of light), say 10-20%.  In general that requires titanic amounts of energy.  (Forget about the common sci-fi scenarios of going into warp drive or jumping through or into hyperspace.  Those are fantasy plot devices with either no science or highly speculative science behind them.)

The mass ratio of fuel-propellant to the rest of the craft, using the most plausible short term option, nuclear pulse propulsion, is something like 10,000 to 1 to reach 10% of c, that is, for every kilogram of spacecraft you want to reach the destination, you’ll need 10,000 kilograms of fuel.  Although multiple stages would help, when we consider everything that would be required to send humans, things start to look pretty bleak.  It’s a little bit more hopeful with uncrewed probes.

One solution being considered is Breakthrough Starshot.  Use tiny probes with light sails attached, which are accelerated by ground based lasers to 20% of c.  The biggest issues with this plan include the cost and logistics of the ground based lasers, the challenges in successfully miniaturizing the craft, and the fact that there’s no way to slow the probes at the destination, so they’d have to collect what data they could during the few hours they had when flying through the destination system.  And their small size limits their transmitting power, meaning sending back the resulting data would require decades.

Another old solution proposed in 1960 by Robert Bussard, is to collect fuel from the interstellar medium.  The Bussard Ramjet (BR) has a tremendous electromagnetic scoop in front of it, which brings in the diffuse hydrogen floating ahead of the craft, compresses it so that it undergoes nuclear fusion, and expels it as propellant.  The idea is that the faster the craft is moving, the more fuel available to it, and the faster it can accelerate.  The biggest issues with the BR is that the interstellar medium has been found since Bussard’s proposal to be far thinner than he believed, and the drag of the scoop limits its overall effectiveness.

Alex Tolley has a post up at Centauri Dreams discussing a new proposal: the Q-Drive, as put forward by Jeff Greason, chairman of the Tau Zero Foundation.  Like the BR, the Q-Drive uses the interstellar medium, but in a different manner.  Unlike the BR, this craft uses an inert stored propellant: water.  (The water is stored as a giant cone of ice in front of the craft, acting as a shield against interstellar particles.)  The water is ionized and accelerated out the back of the craft, propelling it forward.

What comes from the interstellar medium is the power to accelerate the water.  This involves two large magnets that create a couple of magsails (sails made of magnetic fields), but instead of using them as sails, they function sort of like a wind turbine, in that they collect energy by slowing down (relative to the craft) the passing ionic interstellar matter, transferring the difference in kinetic energy to the drive.  The faster the craft is moving, the more energy collected, the faster it can accelerate the propellant, and the higher the thrust.

Tolley’s diagram of the Q-Drive interstellar craft. (Click through for source.)

Notably, the craft has to be initially accelerated to some small percentage of c by other means, such as the nuclear pulse propulsion I mentioned above.  But once that is achieved, that first stage can be jettisoned, allowing the Q-Drive to supposedly then reach speeds around 20% of c.  It can decelerate by pointing the drive in the direction of travel.  (It’s less clear to me how the final stages of deceleration near the destination would work.)

If you’re interested in the details, I recommend reading Tolley’s post.  Tolley is clear that this is something that seems possible in principle, but the practicalities may be another matter.  In particular, there is a question of whether the energy conversion can be efficient enough to make the Q-Drive more effective than just using something like the nuclear pulse rocket for the whole trip.

However, if it does work, or it can be developed into something that works, it may make interstellar exploration far more practical than it currently looks.

If you’re interested in the hard core technical details, check out Jeff Greason’s paper, or his talk on the subject.

Greason’s primary message in the talk is to emphasize the key idea, that drag energy from the surrounding medium (the interstellar medium in interstellar flight, the solar wind in solar system flight) represents an untapped energy source.

It’s been a while since I saw a new idea in this space.  Interstellar travel is a very hard engineering problem.  Hard enough that some scientists think it’s effectively impossible.  It’s nice to see someone make a possible dent in that problem.

Posted in Space | Tagged , , , | 59 Comments

Viruses and the definition of “life”

One of the things we often debate here is the definition of “consciousness,” but consciousness is far from the only concept that is difficult to define.  Others include religion, democracy, free will, and biological life.

Life has a number of definitions, many of which are suitable for particular purposes.  If I recall correctly, NASA, for purposes of detecting it in extraterrestrial environments, defines life as anything that reproduces and undergoes evolution.  But many biologists insist that homeostasis is crucial aspect.

Cells are often referred to as the basic unit of life.  That certainly seems true for the homeostasis definition.

(Interestingly, cells may be the basic unit of life, but they’re not the basic unit of capability.  For that, we have to drop down to proteins, molecular nanomachines that do the actual work in biology.  A simple cell has tens of millions of proteins.  More complex cells, such as neurons, reportedly have tens of billions.  It pays to remember that life began as, and remains, a molecular enterprise, with even cells being vast ecosystems.)

But here’s a question.  Are viruses alive?  It depends on which definition we use.  They reproduce and undergo evolution, producing new species and strains all the time, as most of us are only too aware of these days.  But they don’t have homeostasis.

Outside of a cell, in their “virion” phase, they consist of some genetic material (RNA or DNA) surrounded by a protein coat, both for protection and containing penetration machinery to get through cellular membranes.  Once they’ve invaded the cell, they hijack that cell’s reproductive mechanisms for their own use, reproducing themselves.

Viruses appear to be evolutionarily ancient, perhaps co-evolving along with the earliest cells.  Both cells and viruses may have evolved from pre-cellular biology.  It’s tempting to think of the cells as farmers putting up a fence to protect their mechanisms and resources, and viruses as the raiders coming in to hijack and ransack those mechanisms and resources.

Thinking back to Aristotle’s three layers of soul, he would almost certainly have attributed a nutritive soul to cells.  But I’m not sure he necessarily would have for viruses.  He might have seen them as soulless parasites.

But is that entirely fair?  It seems like viruses simply use the resources available to propagate, just as all heterotrophic life consumes other life to survive and propagate.  In evolution, they also provide an important means of horizontal gene transfer, increasing genetic diversity in non-sexually reproducing species.  And they’re often used today as vehicles for delivery gene editing therapies.

It’s worth noting that viruses are not the smallest infectious agent.  Viroids are even smaller.  Composed of a short circle of RNA with no protein coat, they only infect plant cells.  Their existence seems to have inspired the idea that life began in an RNA world.  Viroids may be leftovers from the earliest primeval life, or proto-life forms.  If viruses are alive, then it seems hard to exclude viroids.

There are even smaller replicating agents: prions.  These are proteins that have become misfolded, with the disturbing ability to transmit their misfolding, leading to a number of neurodegenerative conditions, such as “mad cow” disease.  Are prions alive?  Most biologists say no.  They do reproduce, but I haven’t seen any assertions they undergo evolution.  They may be more like crystals or clay, albeit of a more organic variety.

So what is life?  Does it require a cell?  Or do viruses and viroids count?  Thinking in terms of extraterrestrial life, it seems possible to conceive of mechanisms we might discover that would challenge any definitions we come up with.  Suppose we encountered a sort of organic clay somewhere.

Reality often seems to delight in ruining our little categories.

Posted in Zeitgeist | Tagged , , , | 21 Comments

All adults are vulnerable to COVID-19

The other day I urged you to take COVID-19 seriously.  But in that post, I said that if you were younger than 60 or didn’t have health problems, the virus probably wouldn’t do anything to you.  In retrospect, that was misleading.

A lot of people are saying that we should reopen the economy for people “not vulnerable” to the virus.  The thing is, all adults are vulnerable.  We’ve all fixated too much on the fatality rate.  We also need to look at the hospitalization rate, as well as the ICU rate.  This report from the CDC has that information.

What I want to call your attention to, is this chart from the report:

Bar chart showing high hospitalization rates for all adults

Image credit: US CDC (click through for original)

You can see it in terms of percentage of cases in a table format here.  The TL;DR is that if you’re an adult and get the virus, you have a 20% chance or higher of ending up in the hospital.

Young adults are far less likely to die from the virus, if they have good care.  But being in the ICU is nothing to be blasé about.  And if the virus is allowed to run rampant among the “non-vulnerable” and the health systems become overrun, good care may not be available.

Keep this in mind when considering the calls currently being made by politicians and business people to let up on the social distancing and shelter in place policies.  There’s a reason health professionals are opposed to those calls.

I get that the economic situation is agonizing.  But it’s not like the economy would be robust with an overrun health system.

Posted in Zeitgeist | Tagged , , , | 11 Comments

The sensitive soul and the rational soul

I think examining the evolution of consciousness in animals helps shed light on it in humans.  Admittedly, there are difficulties.  Animals can’t self report using language, which limits just how much of their experience can be garnered from experiments.  Still, taking data from human studies and combining it with animal studies can provide a lot of insight.

One issue is that, in the absence of a precise definition of “consciousness”, there is no sharp line in evolution where everyone agrees that consciousness begins.  Scientists, such as Joseph LeDoux, who seems inclined toward animal consciousness minimalism, and Antonio Damasio, who’s more inclined to see it as widespread,  can agree on all the relevant facts, but disagree on how to interpret them.

This leads many of us to come up with hierarchies.  Those of you who’ve known me a while know mine:

  1. Reflexes and fixed action patterns
  2. Perceptions, representations of the environment, expanding the scope of what the reflexes are reacting to
  3. Volition, goal directed behavior, allowing or inhibiting reflexes based on simple valenced cause and effect predictions
  4. Deliberative imagination, sensory-action scenario simulations assessed on valenced reactions
  5. Introspection, recursive metacognition and symbolic thought

1 seems to apply to all living things, 2 to many animals, 3 to at least mammals and birds, and 4 to the more intelligent species, with 5, at least at present, only appearing to exist in humans.

But I’m far from the only one who’s come up with a hierarchy.  I highlighted LeDoux’s a while back.  Indeed, it appears to be an ancient tradition going back at least to Aristotle.  The ancient Greeks didn’t have a word for “consciousness”, but they did write about the soul.

(The Greek word for “soul” is “psyche”, which obviously is where we get the term “psychology” from, but its etymology is interesting.  It originally meant “to breath”, what probably seemed like the primary difference between living and non-living things.)

Plato’s conception of the soul was something immaterial that survived death, which resonates with the conception in many religions.  Indeed, the word “soul” today is largely synonymous with the immortal soul of monotheistic theology.  A lot of the way the word “consciousness” is thrown around today seems like an unwitting code word for this version of the soul.

Aristotle’s conception was more materialistic.  Most people take him to regard the soul as part of the body and mortal.  (Although, per Wikipedia, there is apparently some controversy about it.)  And he had his own hierarchy back there in the 300s BC.

Hierarchy of Aristotle's versions of the soul

Image credit: Ian Alexander via Wikipedia (click through for source)


  1. The Nutritive Soul, enabling reproduction and growth
  2. The Sensitive Soul, enabling movement and sensation
  3. The Rational Soul, enabling reason and reflection

1 was labeled the “Vegetative” soul in the Wikipedia article on soul; it appears to apply to all living things.  2 applies to all animals.  3 is supposed to apply only to humans.

When I first read about this hierarchy years ago, it didn’t really work for me.  My issue is that many animals appear to be able to reason to at least some degree.  While debatable for fish, amphibians, or arthropods, all mammals and birds appear able to think through options and do short term planning.  This seemed like yet another trait taken as unique to humans but where the real difference is a matter of degree rather than any qualitative break.  Indeed, my thinking is that consciousness, if equated with baseline sentience, requires at least an incipient ability to reason.

However, I’m slowly making my way through Simona Ginsburg and Eva Jablonka’s The Evolution of the Sensitive Soul (which I was alerted to by Eric Schwitzgebel’s review).  Obviously the title refers to Aristotle’s hierarchy, and the goal is to explain what the author’s call “minimal consciousness”, which they note is often referred to as “primary consciousness”, among other names.

And they equate minimal consciousness, sentience, with the sensitive soul.  However, they don’t exclude all reasoning from the sensitive soul.  (Indeed, their unlimited associative learning thesis, as I understand it, will require that it be there, but I haven’t reached that part of the book yet.)  G&J draw the line at symbolic reasoning, involving language, mathematics, art, etc.  That makes the rational soul equivalent to my own level 5 above.

I haven’t read Aristotle directly, so I don’t know if G&J’s characterization is closer than Wikipedia’s version.  And I’m not sure “rational soul” is the most accurate way to describe it.  And the sensitive soul itself has vastly varying capabilities across species.  But minds, both animal and human, are complex things, and trying to boil down the difference to a single phrase is a lost cause anyway.

So, in this framework, all living things, including plants and simple animals, have a nutritive soul, many animals (but not all) have a sensitive soul, and humans a rational soul.    G&J’s goals is to explain the sensitive soul.

What do you think of Aristotle’s hierarchy?  Or G&J’s interpretation of it?  I’m still inclined to use my own more detailed hierarchy (which admittedly still vastly oversimplifies things), but is Aristotle’s easier to follow?

Posted in Mind and AI | Tagged , , , , , | 27 Comments

Star Wars: The Rise of Skywalker

Poster for Star Wars: The Rise of SkywalkerI noticed today that it had been released for streaming, so I went ahead and watched.  (I missed it in the theaters.)  Based on everything that had been said about it, it was better than I expected.  It was entertaining and Abrams managed to get the emotional high points right.  It felt like a decent conclusion to the saga.

And yet this movie, like the entire new trilogy, seemed primarily backward looking in its orientation.  I personally never connected with the new characters as much as the old.  Likely a lot of that had to do with my age.  I was 10 when the original movie came out, but as a middle aged guy, the new story never loomed as large as it did for that kid in the late 70s and early 80s.

And you can tell that the real goal of the trilogy was to act as a bridge between old classic Star Wars and the new batch of movies and shows Disney now wants to produce, shows like The Mandalorian, which I watched and enjoyed, but in a rather bland sort of way.

With that goal, the trilogy felt like something I remember the first sequel of Star Wars managed to avoid.  The Empire Strikes Back, when it came out in 1980, surprised everyone by not being what most sequels had been until that time, a slightly lesser version of the original designed to cash in on the original’s name recognition.  Empire actually continued the story, and is often regarded today as the best in the series.

But this latest trilogy, in many ways, felt like the Star Wars 2 seasoned movie goers were expecting in 1980, particularly with the recycling of the Death Star, Death Star like weapons, and villains.  It was somewhat mitigated by modern first class production values, but the story in many ways feels like a retread.

To be fair to the current producers, George Lucas tried to pull off the same thing with the prequel trilogy that he’d done with Empire, to expand the universe and show us aspects of it we hadn’t seen before, but this time to widespread ridicule and derision.  (Admittedly, the writing for the prequels was also lackluster, and they too were backward looking in their own way, being preoccupied with establishing the background for the classic trilogy.)  So it’s somewhat understandable that Disney took a conservative route with the new movies.

But you have to wonder what the new trilogy might have been if they’d tried the Empire move again.  In interviews, Lucas provided some hints about where he might have gone if he’d made the final trilogy, and it sounds like it would have been very different, verging on metaphysical, exploring the microscopic mechanisms of the Force, which were hinted at in The Phantom Menace, again to fan derision.

Lucas admits fans probably would have hated it, and the example of the prequels didn’t give him much hope.  Based on what I’d read, the chance of that final trilogy happening under Lucas was remote anyway.  Still, if a novel, graphic novel, or something else along those lines about it were ever commissioned, I’d be tempted to read it.

Anyway, The Rise of Skywalker was very entertaining.  It continues to be a space fantasy, with heavy emphasis on the “fantasy” part.  Abrams didn’t concern himself much with canonical consistency or rigorous logic.  But he knows how to tell a story, and I was surprised by how much I enjoyed it.

Have you seen it?  If so, what did you think?

Posted in Science Fiction | Tagged , , , | 10 Comments

Take COVID-19 seriously

Just got back from getting a haircut and a run to the grocery store (which had an atmosphere very similar to the one down here when a hurricane is imminent), during which time I think I heard enough crazy rumors to start my own conspiracy blog.  The worst, by far, were variations that this is all just people freaking out over the flu, or a liberal conspiracy, or some kind of con.  So, I’m sharing this Political Wire blog post, because I think it’s important.

Coronavirus Is Unlike Anything in Our Lifetime

Charles Ornstein: “As a longtime health care reporter, the unfolding coronavirus pandemic represents everything I’ve read about — from the early days of epidemiology to the staggering toll of the 1918 Spanish Flu pandemic — but had not covered in my lifetime.”

“And still, I have been caught off guard by the pushback from top elected officials and even some friends and acquaintances who keep comparing it to the flu.”

“Not one public health expert I trust — not one — has said this flu comparison is valid or that we’re overdoing it. Every single one, from former FDA Commissioner Scott Gottlieb to Harvard professor Ashish Jha, has said we’re not doing enough, that this is far more serious than it is being taken.”

I’m not an epidemiologist, but I listen to the experts.  If you’re younger than 60, this virus probably wouldn’t do much to you.  Congratulations.  Good for you.  (CORRECTION: Actually young adults still have a roughly 20% chance of ending up in the hospital.  Your chance of survival is just better.)  But you’d still be a carrier, a link in the chain threatening people who have a serious chance of being harmed by it: those over 60, or with chronic conditions like diabetes, asthma, heart conditions, etc.

Just about everyone knows and cares about someone in these categories.  (Maybe you’re in one yourself.)  It’s fine to risk your own safety, but don’t be one of those selfish chest thumping jerks who make a big deal about how brave they are while putting others at risk.

Maybe in three to six months we’ll all look back with hindsight knowing that this wasn’t as severe as the experts currently think it is.  Maybe.  But before accepting assurances from anyone who claims to know that right now, ask what evidence or information they have that the health professionals are missing.

Posted in Zeitgeist | Tagged , , , | 43 Comments


Cover for the book, Re-coilI just finished reading J. T. Nicholas’ Re-coil, a space opera novel.  It takes place in the solar system, so it’s not an interstellar story, although there are hints the series might go there eventually.  It involves a future where everyone’s mind can be backed up and instantiated in a new body if they die.  Bodies are referred to as “coils”, so the title, “re-coil”, refers to being put in a new body.  (Not to the kickback of a fired gun, although there is plenty of gunfire in the book.)

Minds are stored in “cores” within the brain of the coil, and can be retrieved if the person dies, but new coils are very expensive.  In some ways, the premise resembles Altered Carbon, but with a couple of important differences.

Unlike in AC, backing up a mind, in and of itself, is not that costly, so everyone is able to do it.  The expense of the body does mean that normal people can’t re-coil casually.  But in this universe, people noticed this was an issue and a business opportunity, so there are insurance policies to provide new coils.  However, the premiums are high, and average people have to devote a substantial portion of their income to paying them.

Most can’t afford a policy that gives them exactly the replacement coil they’d like.  So they can end up in a very different type of body, including one of the opposite sex.  And a low end policy might put someone in a body with defects of one type or another.

Also, being restored to a new coil only includes memories up to the point you were backed up, an important plot point.

As the story starts, Carter Langston is on a salvage team who discover what appears to be an abandoned shuttle heading into the sun.  He spacewalks over and enters it.  Things go horribly wrong and he never makes it out, with the shuttle being destroyed.

Langston awakes in a re-coil facility, with only memories up to his backup, and with the attendants concerned that his mind might have been corrupted.  Shortly afterward, someone tries to assassinate him, and he finds himself on the run, his teammates all missing.

Eventually he discovers a message from his prior self on the derelict shuttle, and realizes that someone is out not only to kill his body, but erase all his backups.  Backup storage is supposed to be among the most reliable and secure assets in the solar system, indicating that whoever is after him, they are rich and powerful.

This was a good book, although I can’t say it was a great one.  Nicholas has a lot of talent, but it seems like he’s still learning the craft.

In particular, he really seems to enjoy his fight scenes.  Throughout most of the book, they are a solid part of the story.  But the final act largely becomes a giant sequence of fight scenes.  It was thrilling but, for me, verged on tedious.  I personally could have seen that final sequence be a bit briefer.  That said, I suspect some will eat it up, and it certainly wasn’t bad enough to stop reading.

So, if you’re looking for solid entertaining space opera, it’s worth checking out!

Posted in Science Fiction | Tagged , , | 21 Comments

AI: An Exercise in Analytical Philosophy

An excellent analysis of the issue! It seems like this is a problem for any interesting philosophical question. I’m always struck by how often philosophical disagreements are really just definitional disputes in disguise. It’s particularly troublesome for any discussion about the mind, about us at the most fundamental level, because people have intense emotions about the conclusions.

Blogging to Share Knowledge

The Question

I recently attended a computing group in which the following question was asked:

Can Software Achieve Human Level Intelligence?

We covered this question over the course of 3 meetings (7-9 hours total).  Those meetings didn’t go well.  We spent hours talking past each other, objecting to arguments, and accusing each other of missing the point.  In the end we gave up and agreed to talk about something else.

How can people spend hours talking about something without anything to show for it?Because we weren’t talking about the same thing and never settled on meanings first to discover that.

After reflecting on those meetings, I thought the following process would have been more productive:

  1. Each person precisely translates the sentence as they understand it.
  2. Replace any contentious terms to avoid arguing over semantics.
  3. Decide if there’s any basis for arguing.

So let’s continue by assuming two arguers: John and…

View original post 527 more words

Posted in Zeitgeist | 44 Comments

The response schema

Several months ago Michael Graziano, and colleagues, attempted a synthesis of three families of scientific theories of consciousness: global workspace theory (GWT), higher order theory (HOT), and his own attention schema theory (AST).

A quick (crudely simplistic) reminder: GWT posits that content becomes conscious when it is globally broadcast throughout the brain, HOT when a higher order representation is formed of a first order representation, and AST when the content becomes the focus of attention and it is included in a model of the brain’s attentional state (the attention schema) for purposes of guiding it.

Graziano equates the global workspace with the culmination of attentional processing, and puts forth the attention schema as an example of a higher order representation, essentially merging GWT and HOT with AST as the binding, and contemplating that the synthesis of these theories approaches a standard model of consciousness.  (A play of words designed to resonate with the standard model of particle physics.)

Graziano’s synthesis has generated a lot of commentary.  In fact, there appears to be an issue of Cognitive Neuropsychology featuring the responses.  (Unfortunately it’s paywalled, although it appears that the first page of every response is public.)  I already highlighted the most prominent response in my post on issues with higher order theories, the one by David Rosenthal, the originator of HOT, who argues that Graziano gets HOT wrong, which appears to be the prevailing sentiment among HOT advocates.

But this post is about Keith Frankish’s response.  Frankish, who is the leading voice of illusionism today, makes the point that, from his perspective, theories of consciousness often have one of two failings.  They either aim too low, explaining just the information processing (a dig perhaps at pure GWT) or too high in attempting to explain phenomenal consciousness as if it actually exists, and he tags HOTs as being in this latter category.

His preferred target is to explain our intuitions about phenomenal consciousness, why we think we have it.  (I actually think explaining why we think we have phenomenal consciousness is explaining phenomenal consciousness, but that’s just my terminological nit with illusionism.)  Frankish thinks that AST gets this just right.

But he sees it as incomplete.  What he sees missing is very similar to the issue I noted in my own post on Graziano’s synthesis: the affective or feeling component.  My own wording at the time was that there should be higher order representations of reflexive reactions.  But I’m going to quote Frankish’s description, because I think it gets at things I’ve struggled to articulate.  (Note: “iconsciousness” is Graziano’s term for access consciousness, as opposed to “mconsciousness” for phenomenal consciousness.):

Suppose that as well as an attention schema, the brain also constructs a response schema—a simplified model of the responses primed by iconsciousness.  When perceptual information enters the global workspace, it becomes available to a range of consumer systems—for memory, decision making, speech, emotional regulation, motor control, and so on. These generate responses of various kinds and strengths, which may themselves enter the global workspace and compete for control of motor systems. Across the suite of consumer systems, a complex multi-dimensional pattern of reactive dispositions will be generated. Now suppose that the brain constructs a simplified, schematic model of this complex pattern. This model, the response schema, might represent the reactive pattern as  a multi-dimensional solid whose axes correspond to various dimensions of response (approach vs retreat, fight vs yield, arousal vs depression, and so on). Attaching  information from the model to the associated perceptual state will have the effect of representing each perceptual episode as having a distinctive but unstructured property which corresponds to the global impact of the stimulus on the subject. If this model also guides our introspective beliefs and reports, then we shall tend to judge and say that our experiences possess an indefinable but potent subjective quality. In the case of pain, for example, attended signals from nociceptors prime a complex set of strong aversive reactions, which the response schema models as a distinctive, negatively valenced global state, which is in turn reported as an ineffable awfulness.

Now, Frankish is an illusionist.  For him, this response schema provides the illusion of phenomenal experience.  My attitude is that it provides part of the content of that experience, which is then incorporated into the experience by the reaction of all the disparate specialty systems, but again that’s terminological.  The idea is that the response schema adds the feeling to the sensory information in the global workspace and becomes part of the overall experience.  It’s why “it feels like something” to process particular sensory or imaginative content.

This seems similar to Joseph LeDoux’s fear schema.  LeDoux’s conception is embedded in an overall HOT framework, whereas Frankish’s is more at home in GWT, but they seem in the same conceptual family, a representation, a schema of lower level reactive processes, used by higher order processes to decide which reflexive reactions to allow and which to inhibit.  It’s the intersection between that lower level and higher level processing that we usually refer to as feelings.

Of course, there is more involved in feelings than just these factors.  For instance, those lower level reflexive reactions also produce physiological changes via unconscious motor signals and hormone releases which alter heart rate, breathing, muscle tension, etc, all of which reverberate back to the brain as interoceptive information, which in turn is incorporated into the response schema, the overall affect, the conscious feeling of the response.  There are also a host of other inputs, such as memory associations.

And it isn’t always the lower level responses causing the higher level response schema to fire.  Sometimes the response schema fires from those other inputs, such as memory associations, which in turn trigger the lower level reactions.  In other words, the activation can go both ways.

So, if this is correct, then the response schema is the higher order description of lower level reflexive reactions.  It is an affect, a conscious feeling (or at least a major component of it).  Admittedly, the idea that a feeling is a data model is extremely counter-intuitive.  But as David Chalmers once noted, any actual explanation of consciousness, other than a magical one, is going to be counter-intuitive.

Similar to the attention schema, the existence of something like the response schema (or more likely: response schemata) seems inevitable, the attention schema for top down control of attention, and the response schema for deciding which reflexes to override, that is, action planning.  The only question is whether these are over simplifications of much more complex realities, and what else might be necessary to complete the picture.

Unless of course I’m missing something.

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