A repost, but I figure you people will appreciate this:
"Yvain" at Less Wrong posits a Bayesian basis for monothematic delusions such as anosognosia. What is anosognosia, you ask?
Anosognosia, a condition in which extremely sick patients mysteriously deny their sickness, occurs during right-sided brain injury but not left-sided brain injury. It can be extraordinarily strange: for example, in one case, a woman whose left arm was paralyzed insisted she could move her left arm just fine, and when her doctor pointed out her immobile arm, she claimed that was her daughter's arm even though it was obviously attached to her own shoulder. Anosognosia can be temporarily alleviated by squirting cold water into the patient's left ear canal, after which the patient suddenly realizes her condition but later loses awareness again and reverts back to the bizarre excuses and confabulations.
It is but one of the monothematic delusions in the class Yvain is addressing. For instance, you also have the Capgras.
In the Capgras delusion, the patient, usually a victim of brain injury but sometimes a schizophrenic, believes that one or more people close to her has been replaced by an identical imposter. For example, one male patient expressed the worry that his wife was actually someone else, who had somehow contrived to exactly copy his wife's appearance and mannerisms.
What do these types of delusions (and some forms of schizophrenia) have in common? Generally, damage to the right frontal lobe of the brain. Beyond that, several different classes of theories have been advanced. There is, for example, a "single factor" theory based on "belief shift" for anosognosia.
Ramachandran suggested that the left brain is an "apologist", trying to justify existing theories, and the right brain is a "revolutionary" which changes existing theories when conditions warrant. If the right brain is damaged, patients are unable to change their beliefs; so when a patient's arm works fine until a right-brain stroke, the patient cannot discard the hypothesis that their arm is functional, and can only use the left brain to try to fit the facts to their belief.
Alas, a "belief shift" theory of this sort, while plausible in the case of anosognosia, doesn't seem to work well for other, similar monthematic delusions with similar patterns of brain damage. One might plausibly have difficulty shifting from the belief that one's leg is healthy to the belief that one's leg is unhealthy based on a single type of damage. But what
about the belief that one's spouse is a body-snatcher type alien? It's an unreasonable belief on its face. It's not simply that the patient might have damage that makes them unable to update their beliefs to fit a new reality; an overarching theory must also explain why any sort of credence is given by the patient to beliefs that fit no reality.
Enter "two factor" theories. These posit that there is both damage that prevents belief updating (i.e. nerve damage that prevents the brain from feeling emotion on seeing one's spouse) and a second sort of damage that forces a fairly wacky reason for the sensory input produced by the first sort of damage (i.e. I feel nothing, so my wife must actually be a really clever impostor!) This gets around the fact that "single factor" theories, while viable for some simple delusions, would in other cases require the patient to be (to quote Yvain) "really stupid". After all, if confronted with a lack of emotional or physical response, you'd have to pretty dumb/gullible to leap to the idea that "my wife is actually a disguised spy" or "my hand is being controlled by aliens". Given that the distribution of intelligence in patients seems to be an otherwise normal one, this is unreasonable. Additionally, many patients with similar forms of brain damage do not develop delusions about why this is the case, but simply soldier on with a handicap like not being able to feel their arm, etc.
The difference appears to lie in the presence or absence of another, more specific form of damage, to the right dorsolateral prefrontal cortex (RDPC.) It is only those with damage to the RDPC that appear to develop not just sensory issues, but wacky theories to explain those sensory issues to themselves. The earlier theory then takes the RDCP to be part of a belief evaluation module in the brain, and posits that damage to it makes it difficult to update one's beliefs.
In his first papers on the subject, Coltheart vaguely refers to the RDPC as a "belief evaluation" center. Later, he gets more specific and talks about its role in Bayesian updating. In his chronology, a person damages the connection between face recognition and emotion, and "rationally" concludes the Capgras hypothesis. In his model, even if there's only a 1% prior of your spouse being an imposter, if there's a 1000 times greater likelihood of you not feeling anything toward an imposter than to your real spouse, you can "rationally" come to believe in the delusion.
But as Yvain notes, this is still problematic. People don't walk around randomly thinking that their wife is a spy or their arm belongs to an alien, so you're still left with the puzzle of why such an unlikely belief might get into position in the first place even if you can explain why it can't be taken out later.
Enter the McKay theory, which posits that the problem is with the patients' ability to use Bayesian priors. For those of you unfamiliar, in simplified fashion the idea in Bayesian statistics is that your use of current evidence should be taken not in isolation, but as modifying your prior beliefs about the situation. So if you happened to get a bit of evidence that, say, the President was born in Kenya or Mitt Romney never paid any taxes, you should (unless you had already developed very strong priors in that direction based on other evidence) tend to modify your belief in the likelihood of such a thing only a little. But our RDPC patients apparently can't do that which results in what Yvain calls the Super Base Rate Fallacy.
For them the only important criterion for a belief is explanatory adequacy. So when they notice their spouse's face no longer elicits any emotion, they decide that their spouse is not really their spouse at all. This does a great job of explaining the observed data - maybe the best job it's possible for an explanation to do. Its only minor problem is that it has a stupendously low prior, and this doesn't matter because they are no longer able to take priors into account. This also explains why the delusional belief is impervious to new evidence. Suppose the patient's spouse tells personal details of their honeymoon that no one else could possibly know. There are several possible explanations: the patient's spouse really is the patient's spouse, or (says the left-brain Apologist) the patient's spouse is an alien who was able to telepathically extract the relevant details from the patient's mind. The telepathic alien imposter hypothesis has great explanatory adequacy: it explains why the person looks like the spouse (the alien is a very good imposter), why the spouse produces no emotional response (it's not the spouse at all) and why the spouse knows the details of the honeymoon (the alien is telepathic). The "it's really your spouse" explanation only explains the first and the third observations.
I think this theory has a certain elegance to it. Additionally, it begins (if correct) to isolate part of the brain as being involved in higher-order functions like prediction and decision making under uncertain conditions. Very cool stuff!
This is awesome! Something seems off to me
(#287371)however in the basic understanding of these monothematic delusions. I have a feeling it's probably backwards, for instance, to say that the Capgras delusion is primarily a theory on top of a malfunctioning mental state. Rather it seems to me that the mental malfunction is fairly overwhelming, and whatever explanatory theory the patient comes up with is driven mostly by the need to come up with a workable explanation of that overwhelmingness. The theory part, in other words, is strictly post-facto. Take the extreme form of Capgras, where everyone you know, along with your house, the world, and time itself appear to be "wrong." You're basically living in a doppelganger world, and all that's missing is the emotion we know as "familiarity," without which life has no continuity. The important thing is not whether you believe you're in the Twilight Zone and everyone's been replaced by aliens...the important thing is that your brain is capable of generating no more reasonable explanation. One doppelganger theory is as good as any other, in other words.
The core of our language ability is rooted in proprioception: me, myself, my arm, my house, you, your stupid face, etc. Unplug the part of the brain that makes sense of proprioception, that provides the tenor for which the most elemental parts of language are the vehicle, and it is no longer possible to form a "reasonable" theory about identity based on prior information (those priors are no longer available).
I think it might not make sense to think of the RDPC as a "belief evaluation" center, in the sense that a malfunction creates people with calcified, unshakeable idees fixes. Rather, it sounds more like the center that gives me my "me-ness", my arm its "my-ness", you your "you-ness" and so on. In other words, it produces the feeling of familiarity that we use to verify for ourselves that in fact the world hasn't been changed into an identical zombie world while we weren't looking. You may not have any *evidence* that aliens are messing with you, but your most basic *evidence* that roots you in the world, indeed the core function that makes empiricism itself possible, is missing for you, and that experience of estrangement is so overwhelming that even the most ridiculous theories seem plausible.
Another way to put it: there is nothing that connects the "me" right now to the "me" five minutes ago, to the "me" 15 years ago, except the warm fuzzy feeling I have that those people and I are one and the same.
M Aurelius was probably right.
Boy was I tired when typing this out.
(#287384)Here's what I was trying to say, hopefully in plainer English: you don't need a two-factor theory to explain the origin of "really stupid" beliefs in either of the cases mentioned. Alternate hypothesis: the part of the brain that provides "emotional proprioception" may be the only thing that keeps the world from seeming like it was replaced by aliens (or some invisible power) every few moments.
Heraclitus famously said you can never jump in the same river twice. Meaning the world is never identical to itself from moment to moment. It really isn't the "same" world, except by convention. At the same time our senses are disjunctive...we see, hear, and perceive in pulses, waves, on-off periods (when we sleep), altered states, etc. We can't keep watching the world continuously, like a convenience store camera, and so we can't be absolutely sure it hasn't been replaced by a very clever replica. Or rather, given the Heraclitus principle, we can't continuously observe the flux to make sure that each state transition we observe is legit & caused by natural, non-alien processes. The world is disjunctive, and so is our perception of it.
The brain is built to smooth out this disjunctive parallax, probably in several different ways. But one important way is through emotional cathexes: we look at the world and it seems different, but feels the same. Like the river...never precisely the same water, never precisely the same width or depth, obviously eddies & turbulence are always changing, surface reflections are never the same. But emotional proprioception tells us this river is similar enough to the one I drove across on that trip to St. Louis that it passes the brain's test for sameness. The river's voter ID checks out, so our brain attaches a fuzzy sensation of familiarity to it. Despite the actual, observed evidence that this river has never been precisely this way before, and never will be precisely this way again, we get a warm flood of recognition: Ahh, that's the Mississippi! The mighty Mississip', heh heh heh. The Ole Miss! The Old Man! Deeeeeep riverrrrrrrr....
The important thing to stress here is how completely artificial that fuzzy feeling of recognition really is. But without it, with people whose RDPC is on the fritz, we are left with essentially no evidence that the world is the "same" world we knew. Because sameness is a proprioceptive illusion created by a healthy brain. The world isn't the same. It really has been changed by unseen forces while we weren't looking. Sure, we can detect similarity (assuming that part of the brain's still working), but identicality no longer exists for us (and probably doesn't exist at all).
In animation & robotics, there's a phenomenon called The Uncanny Valley. It's the response we have when a robot, animatronic, or animated character looks almost but not quite life like. It's a feeling of revulsion: the thing gives us the creeps. Kill it! Kill it with fire! This results from failed similarity: the brain is incredibly perceptive when it comes to sorting out real from fake when it comes to faces, emotions, lies, etc. Lesions in the RDCP, on the other hand, would seem to be a related type of failure. The perception passes the brain's similarity/identity test, but we still don't get the surge of relief that comes from recognition. Something's weird here! Which must mean, the brain warns us, that we're looking at a very clever fake.
TL;DR - Our sole evidence that the world hasn't been replaced by an alien zombie world that looks just like it is a squishy emotional feeling that has nothing to do with the real world. Pure observation would indicate that the world really *is* replaced by slightly off variations of itself with each passing moment.
M Aurelius was probably right.
I think it's even easier than that
(#287403)from what I've read "the brain" is actually a bunch of separate processing centers than pre-process information and there are a few integrating sites that discriminate between the various inputs they receive to construct what we perceive as reality. You only need damage to one of those integrating sites to start accepting thoughts that previously would have been discarded because they don't fit in with past experiences.
I blame it all on the Internet
How does this differ from....
(#287406)....the idea of RDPC damage described above, though? It sounds like you're describing the same idea in less detail.
"Unfortunately the universe doesn't agree with me. We'll see which one of us is still standing when this is over." -- Eliezer Yudkowsky
I guess the difference is
(#287418)there's no "creation" of wacky theories, they're being generated all the time, even in healthy brains, at a preconscious level. The damage just means that they're not filtered out anymore. Now why crazy theories become fixed is a question, since that kind of damage would lead you to expect a bunch of crazy theories over time. This is a problem with the Bayesian model too, I would think, unless the damage also reinforces the first idea that comes along. But then you'd expect the damage to cause a random set of misconceptions, and the ones cited all seem to include separateness and difference rather than similarity.
EDIT: Oops, didn't see #287405 before I posted. That would actually support the "first theory in gets reinforced" idea.
I blame it all on the Internet
I dunno.
(#287405)One objection immediately comes to mind, and it's the same one that arises in response to the initial "one factor" model described above. That is, it doesn't look parsimonious in relation to the variety of possible monothematic delusions. For instance, you can get the opposite of the Capgras, the Fregoli.
In this case, it isn't the brain failing to create our "fuzzy familiarity" but instead creating unwarranted familiarity out of the unfamiliar. But it appears to stem from similar damage in similar parts of the brain. The "two factor" Bayesian idea, OTOH, can cover both sides with one theory.
"Unfortunately the universe doesn't agree with me. We'll see which one of us is still standing when this is over." -- Eliezer Yudkowsky
I think what I'm saying still holds,
(#287409)and it can be boiled down to this: the world's "sameness" is basically a fuzzy emotional illusion created by our brains. The actual world is a bunch of molecules dancing in empty space. Deprived of the brain's illusion (or given too much of it), we have to form some other theory about how the world keeps changing on us, and the one theory that science considers most reasonable (the world isn't actually changing) is self-evidently false.
Recognition is an illusion. Deprived of the illusion, the recognizable world doesn't exist. Because, you see, the real world actually is a zombie doppelganger world, replaced each moment by mysterious unseen forces.
So you only have to remove one process - the brain's emotional attachment to "same-enough" - in order to explain weird, unshakable theories about the world. (Those theories are actually accurate, at least until the person goes as far as to name the planet the aliens are from, without evidence, etc. For those types of delusions you might indeed want to go looking for a second factor. Anyways: you're *not* the same identical person as the one who wrote the diary. I'm not the same person I was when I woke up this morning. The planet isn't the same. Nothing is ever identical.)
M Aurelius was probably right.
I think you've gone too
(#287419)far with this idea that "sameness" is an illusion cooked up by our brains. While it's true that the universe is evolving at all times, and nothing is the exactly the same, there's no doubt that various piles of molecules existing now can be correlated with the piles existing yesterday, with a very high degree of accuracy. You don't need an RDPC to do it, either, a computer program can easily (and objectively) tell that the Tropical Depression 7 over Mexico today is the "same" as the one that was over the gulf yesterday.
I'd also add that people with something like Capgras are probably severely disabled by it, and not just in social interactions. The
ideafact that macroscopic things evolve in a continuous manner rather than abrupt, discrete replacements is pretty damn important. I imagine if you dumped a Capgras sufferer in the woods they'd have a much lower survival rate than someone without."Sameness" isn't a physical property, is my point.
(#287423)It's basically no more than a feeling we have about things when we recognize them. Does an orange experience itself as an orange? No, it's just a cloud of molecules somewhat denser than the cloud of molecules making up the air. A homerun baseball can be "correlated with a high degree of accuracy" with the baseball that left the pitcher's fingers moments before, but there's nothing physically about the baseball that makes it the same ball in the way we mean when we say things are the same. The ball has no physical identity any more than the collective starlight we can see in a few degrees of night sky has an identity. The identity of things is a property that's only useful to us as beings that need to "recognize" things in order to interact with them.
Your computer program doesn't recognize sameness either...it correlates data from weather stations & satellites, and it is programmed to mark certain bands of data and draw those bands to our attention. For the computer it makes no difference how the bands are selected. The computer would be just as happy saying today's Tropical Depression 7 is very, very similar to yesterday's Tropical Depression 7, but it can't be the same weather phenomenon because it's in a different place, with different wind energies, etc. The difference or sameness is strictly speaking irrelevant and arbitrary. Also, it doesn't matter to the computer (or to the air molecules) exactly who or what caused them to be in their current configuration: maybe solar energy did it, maybe aliens. Makes no difference: molecules don't need to have a theory of intention. Likewise the computer doesn't care if TD7 is actually the same storm as yesterday, or only a very similar one.
M Aurelius was probably right.
By this standard
(#287427)you might as well say that "temperature" isn't a physical property, either. It's just a number representing, in a very crude statistical way, the agitation of a large collection of particles, that just happens to be useful to people deciding whether to sit on black marble benches.
The definition of "sameness" hasn't been as closely specified by physicists, but you could certainly produce a definition based on the (a) types and states of particles in a given region at a given time, (b) how closely the types and states correlate with another region at another time, and (c) - this one's the most important - whether that correlation varied in an continuous manner from the earlier time to the later time. Kind of like the concept of homology.
Yeah, it's arbitrary, but you could say that about any matching of a word to physical reality.
I'd also say again that it's an extremely useful property. The property of sameness is essential for one to realize that the black bench that burned your buttocks 100 ms ago is the same as the one that's burning your buttocks now, and that 100 ms from now will almost certainly still be hot, because it will be the same one. If it was a different bench every time you'd have to start over on your evaluation every 100 ms, and could never decide to stand up.
Wasn't it Heraclitus
(#287449)Common sense tells us that the bench of a second ago is the same bench now - it's also a matter of physics as you point out. But it's much harder to maintain that the idea or emotional attachment of a second ago is the same as the one I'm entertaining now. Wasn't it Heraclitus who claimed we couldn't put our foot twice into the same river?
I'm starting David Bohm's "Wholeness and the Implicate Order" which has lots to say on Physics and the nature of consciousness.
You will kill 10 of our men, and we will kill 1 of yours, and in the end it will be you who tire of it. - Ho Chi Minh
Just gotta say more...
(#287428)I can't believe you're dissing what I now realize is my favorite of all physical properties, namely, "sameness". You can't even get past Newton's First Law without it:
An "object". WTF is that? Why, it's something that has this thing you call sameness. Suppose you come up with some other way to define "object" - then what about "motion" - it's when the same object appears at different locations at different times.
You take away my belief in sameness and I'll have to go see one of those consulting philosophers they have in Italy.
Well Newton's Law is a law, not a description of a
(#287478)specific object. Obviously the ideal objects described in the law don't blink in and out of existence. They're ideal!
What I'm saying boils down to this: for any real, macro-level object, there are two equally valid ways to describe its ontology. In the more common way, the brain correlates two discrete observations. Let's say a) baseball cracking off the bat and b) baseball four inches from my nose. Quite accurately, the brain can consider those two observations to belong to the "same" baseball. It's the same ball! It must be traveling pretty fast! Towards my nose, duck!
But it would also be physically accurate to say that the ball cracking off the bat, and the ball that's about to turn my nose into a root vegetable, are very similar, but not identical baseballs. Aside from different momenta & energy levels, the ball that's about to hit my nose has a bruise on it where it's been smacked by a wooden bat. It's several hundred thousand molecules lighter, the winding of strings inside has been disarranged in hundreds of ways, the ball itself has changed shape ever so slightly, etc. The second ball has been changed, albeit in a way that doesn't much matter for my purposes. It is no longer the same identical baseball. Of course this is true at every moment...the dancing, vibrating molecules in the ball exchange places with air molecules, several billion rubber, leather & twine molecules undergo oxidation, etc. The ball is constantly changing. It's only from my point of view and because I don't care about those minor, perpetual alterations that it makes sense to consider it the "same" ball.
Every object is effectively Theseus' ship, at every moment, and so both ways of describing objects are accurate...they are "the same" for our purposes, but constantly changing at a lower level we don't often care that much about.
Far more distressing when you can't shake the idea that people you do care about are no longer the same.
M Aurelius was probably right.
Too far, Jordan
(#287439)sameness is a physical property. Whether you think time is continuous or step-like, a macro object persists and maintains its characteristics. A baseball is a baseball, and can be more than "closely correlated" with another (although at our current state of technology the proof is usually destructive in nature). Quantum level indeterminacies disappear at the classical level* and identities can be established.
Some of your other points are a bit strange, oranges and computer programs don't have self awareness so to say that they "experience" anything is a bit of a stretch unless you're talking shorthand about the physical forces that are acting on them. An orange doesn't experience itself any more than a computer program does.
* now why quantum level effects seem to disappear when the sizes involved get above about a micron or so (except for very exotic forms of matter) is an open question, and AFAIK there's no good theoretical reason why that effect exists.
I blame it all on the Internet
"I imagine if you dumped a Capgras sufferer in the woods ...
(#287457)... they'd have a much lower survival rate than someone without."
That seems to assume that the deficits affect reasoning capacities quite generally rather than being localized, where that's not a typical feature of delusions.
If it's just people
(#287469)they don't recognize, maybe so. If the entire "sameness recognition" engine is gone, it seems there would be problems with things like finding the tree where you cached your food, recognizing the cave that had the angry bear in it, etc.
Of course I recognize that people can function with some level of delusions. For example right here we have....oh nevermind.
"If the entire "sameness recognition" engine is gone"
(#287479)The existence of dissociable damage to things like facial recognitional capacities and related localized delusions like Capgras - which doesn't affect object identification generally - is evidence against a domain-general 'sameness recognition' engine in the brain.
I don't know if this is on point
(#287456)But little the brain does is going to rule out skeptical hypotheses - the possibility of replica hypotheses will always be present, since the info. the senses receive is compatible with a replica world. So that's just not an interesting issue for brain science.
There's a separate issue of how the brain combines sensory info. from different modalities and over time from the same modality, and ascribes it to the same features in the world - the binding problem. But this isn't typically taken to be solved by emotional valence, i.e., that each piece of information feels as if it belongs to the same thing.
There's something else in perception that a. doesn't even posit skeptical hypotheses in most cases and filters out higher level ones in most others.
The binding problem!
(#287477)I'm pretty sure that's what I was on about, sort of, and I'm glad there's a term for it even though the term sounds kind of like a problem that could be cleared up with Fiber One.
I'm not sure why ruling out skeptical hypotheses is "not an interesting issue for brain science" - it seems like one of the more interesting & important things the brain does. Maybe it's because we're so confident in our folk wisdom about physics that we have trouble conceiving that "binding" might not be derived from any physical property of objects in the first place?
This is true, and maybe it helps explain why the Capgras and Fregoli delusions focus on people. Subjects sometimes say it feels as if the world has been replaced, or if time has been altered in some disturbing way, but the far more disruptive & unsettling delusions focus on people. Objects translating through space...a baseball...aren't very emotionally cathected for us, and so we don't much care whether they are the "same" or have been replaced by identical objects with identical trajectories, etc. So a person whose brain is completely unable to bind objects can still catch a baseball, assuming their reflexes are unaffected. For functional purposes in the world, you can catch and throw the "same" baseball, or a baseball that keeps getting replaced by a very similar one every few moments...both are accurate ways of representing physical reality.
But mothers, husbands, children, etc. are much more important to us, and so an inability to filter out skeptical hypotheses about them is inordinately more distressing. We really can't function well when we think the people we care about are discontinuous (or, in the Fregoli delusion, we think the people we care about are everywhere in disguise).
M Aurelius was probably right.
The reason I was saying that the rejection of
(#287480)extreme "matrix-like" skeptical hypotheses isn't in general interesting for brain science is that in the normal case such hypotheses are never generated in the first place.
So there's typically no process of rejecting them that needs description.
"Subjects sometimes say it feels as if the world has been replaced,"
That doesn't suggest, to me anyway, that there's any process in normals that considers whether the world has been replaced and then rejects that hypothesis. It suggests that Capgras subjects insert these emotions and ideas into processes that normally aren't influenced by such background information.
"a person whose brain is completely unable to bind objects can still catch a baseball"
We're using "binding" a bit differently here. Failing to "bind" for perception and object tracking as normally understood would make it difficult to catch a baseball, since perceiving the baseball means "binding" together its shape, color, and motion into one bundled object.
Catchy, if I couldn't annoy professionals with inane objections
(#287486)to established theories, then I might have to give up going on the internet.
I think I might be garbling up at least two distinct processes, namely perception and emotional cathexis (which I think of as "binding"). I think you'd agree that perception is largely hypothetical in nature, meaning the brain continually extrapolates from sensory input to make predictions about objects, movement, people, etc. These predictions are generally accurate enough for government work (a baseball will hurt if it hits us, Romney will lie if he makes a speech, etc.). And so it isn't really interesting to find out whether/how the brain considers & rejects alternate predictions about objects. Although there are marginal cases (the duckrabbit illusion, the spinning dancer) where the brain can be tricked into leaping after a wrong hypothesis. Gifted liars can make us believe that they are sincere in their intentions, so that we cannot perceive a threat. In those cases it matters whether things are the same, or are continually what they appear to be, but in most cases of perception it just isn't that interesting.
However I still feel that there might be an emotional component to identifying things as "the same." If there's a cluster of brain processes that we can call "recognition," then it would seem to me that they work something like this: the brain tests a hypothesis about the person or object, via perception. If the object passes the test as being close enough to what the brain was predicting, then we recognize it, i.e. accord it a feeling of familiarity, which is far more of an emotion than it is an observation.
This happens automatically & unconsciously, so we only notice it when it fails to work. Then we get a feeling of uncanniness, deja vu, suspicion & paranoia, etc.
M Aurelius was probably right.
I suspect there are several paths processing
(#287488)object tracking. That baseball gets handled by a highly reactive/reflexive system that just identifies a threat. Details aboyut baseballs might get filled in and linked to previous baseball experience after the fact if some evidence presents itself - like a baseball hitting the wall behind you and rolling to your feet. Meeting, identifying and gauging the emotions and motives of people is probably handled by a completely different cct. . IOW I doubt the brain is programmed by OOP professionals with an objects/methods/instances methedology where a person is an instance of the the object human etc.
I read a long time ago of an interesting optical illusion experiment where scenes were revealed to the subject by suddenly switching on the light. They were instructed to react to the scene (grab the ball, or whatever) as quickly as possible as soon as the light came on. The scenes themselves were carefully constructed so that as a vector image they were illusions but their shading revealed their true nature. High speed camera tracking of the subjects hand showed that initially the brain seemed to process the scene as a vector image and the hand moved as if fooled by the illusion. After a few milliseconds the path of the hand corrected as the shading information was integrated. All of this was completely subconscious and the subject was not aware of any ambiguity in the scene.
Another interesting little article I read was on the evolution of electrical ccts by natural selection. A group of researchers started out with a goal - measure temperature for example - and chose a series of basic building blocks. I think they started with a selection of random designs and over a series of generations chose the best one and then otereated by generating a series of child ccts that differed from the parent by just 1 step.
What they ended up with were ccts that were constructed of digital components like and and not gates but were making use of their analogue properties rather than their digital ones. So a cct that might have the job of turning a light on and off every second would work perfectly until someone opened the window and the temp in the room dropped. This changed the important analogue properties of digital compents such as resitance and they would fail catastrophically.
I often wonder if we, with our tools for understanding digital logic systems, fail to account for analogue properties of the mind. The brain has, like those ccts, evolved after all. I see no reason why it wouldn't use effects like temperature, pressure, proximity of neurons as happilt as connectivity.
Tangentially and coincidentally
(#287374)you might be interested in this.
literally anything can become right or wrong if the dominant class of the moment so wills it
Thanks!
(#287377)Apropos of nothing, there appears to be some controversy over whether Keynes actually ever said that.
"Unfortunately the universe doesn't agree with me. We'll see which one of us is still standing when this is over." -- Eliezer Yudkowsky
Heh.
(#287379)"Statistics is an imperialist discipline....". This explains my affinity for it, clearly.
"Unfortunately the universe doesn't agree with me. We'll see which one of us is still standing when this is over." -- Eliezer Yudkowsky
Look for simplicity and elegance
(#287442)in things like physics and mathematics, but not brain injury. I mean think of it: the brain houses this stupendously complicated computer with millions of different neuron parts. There must be millions of different ways to injure it, and millions of different effects caused by these injuries. There's no reason why this sort of thing should bow to reductivist explanation.
"I don't want us to descend into a nation of bloggers." - Steve Jobs
"simplicity" an "elegance"
(#287455)are names for constraints on hypothesis formation.
Otherwise the process is unconstrained and therefore not characterizable.
The challenge is to say what the constraint mean in a context where many disscoiable parts are operating in conjunction.
No contraints means you've given up.
I don't understand
(#287504)your third graf.
"I don't want us to descend into a nation of bloggers." - Steve Jobs
Sometimes I Think That Reality is Just Something We Paint...
(#287459)...out in front of ourselves. With luck, we move forward with brush in hand painting furiously as we go. Some paint better than others, but most of it is pure fiction...on the emotional level. The level that matters. I concede that there is a physical existence of ourselves and reality.
Which doesn't care a whit for us.
Mr. Tony Scott, younger brother of Ridley Scott, and the first to gain fame directing movies, killed himself by jumping off Vincent Thomas Bridge in San Pedro this afternoon. He left his car parked in an Eastbound lane of the bridge and a suicide note in his office. He was 7 years younger than brother Ridley.
So what was going on? He was busy, successful, his mind just broke. A lot of cruel things are being said about Jesse Jackson Jr being in a mental facility for depression and being Bi-Polar. I can only recommend seeing Lars von Triers magnificent movie Melancholia on the subject.
More interesting, what does this do for the living? Where is Ridley at now, can he go forward? Likewise, when you twist your head just a little, what happens to Christopher Nolan after the Aurora, Colorado shooting? Creatively, what happens after bad events?
We all live, we all suffer though terrible things, but...reality, whatever that bitch may be, is a bitch.
Treat her nice!
~~~~
MACBETH
Hang out our banners on the outward walls;
The cry is still 'They come:' our castle's strength
Will laugh a siege to scorn: here let them lie
Till famine and the ague eat them up:
Were they not forced with those that should be ours,
We might have met them dareful, beard to beard,
And beat them backward home.
A cry of women within
What is that noise?
SEYTON
It is the cry of women, my good lord.
Exit
MACBETH
I have almost forgot the taste of fears;
The time has been, my senses would have cool'd
To hear a night-shriek; and my fell of hair
Would at a dismal treatise rouse and stir
As life were in't: I have supp'd full with horrors;
Direness, familiar to my slaughterous thoughts
Cannot once start me.
Re-enter SEYTON
Wherefore was that cry?
SEYTON
The queen, my lord, is dead.
MACBETH
She should have died hereafter;
There would have been a time for such a word.
To-morrow, and to-morrow, and to-morrow,
Creeps in this petty pace from day to day
To the last syllable of recorded time,
And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!
Life's but a walking shadow, a poor player
That struts and frets his hour upon the stage
And then is heard no more: it is a tale
Told by an idiot, full of sound and fury,
Signifying nothing.
Best Wishes, Traveller
The McCay "theory" doesn't look like any kind of theory
(#287460)There are a couple of ways to point this out. The first is that Bayesianism isn't really a specific model of inductive reasoning, it's a framework or schema.
So for example a strictly Bayesian framework doesn't say anything whatsoever about how to assign priors, and you can input whatever probability distribution to priors you want into framework that incorporates Bayes rule such that many different kinds of updating come out as "correct".
Put another way, it's not very informative to be told that there's a "Bayesian" theory "which posits that the problem is with the patients' ability to use Bayesian priors," since Bayesianism is essentially silent on assigning prior probabilities.
Ok, another angle to my critique. Many folks have additional commitments about what should constrain Bayesian priors like "simplicity" and, relatedly, Occam's razor (which really have nada to do with Bayesianism per se).
I think you can see this in the discussion of Capgras syndrom you link (the imposter delusion): "we as sane people know that the telepathic alien hypothesis has a very low base rate plausibility because of its high complexity and violation of Occam's Razor"
To me, this exepmlifies what I sometimes run across with Bayesians, namely they help themselves to notions like "simplicity," "complexity," "Occam's razor," etc. w/out sufficient explication. (Or so it seems to me.)
So consider what an inability to use Occam's razor in general - viz. don't multiply entities beyond necessity - would really entail.
The delusional subject would be just as likely to posit an entirely different imposter at each and every moment for every entity she encounters. Not necessarily from the CIA. But equally likely from a different agency/org, from a foreign/alien government, etc. every time she encountered a friend, spouse, family member, etc. And why would she only posit these for close acquaintances, as is common for Capgras sufferors, versus any other object?
Essentially, this kind of appeal to a "deficit in the way priors are assigned" probably isn't a genuine explanation b/c no real explanation for how Bayesian priors are assigned has ever been given in the first place.