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Non-computability – Gödel, Turing machines and brain

 

This article is a subsection of the main article
How physics changes the way we look at mind

The current (and almost universally) accepted view on consciousness is that it is an emergent phenomenon arising from the complex interconnections and communication among neurons. Artificial Intelligence researchers latch their idea of a robotic equivalent of the brain on this concept of consciousness. Basically they believe that the creation of an ‘intelligent’ processor is only hindered by the tedious job of writing out algorithms powerful and complex enough to mimic brain’s functions.

But is that optimism farfetched?

Kurt Gödel’s incompleteness theorem doesn’t actually set some arbitrary limit to the process of acquiring knowledge through human or machine effort. And Penrose doesn’t say it does either. The Incompleteness Theorem is cited by Penrose as an example of how human brain can go beyond a computer or a robotic processor brain. Computers and Artificial intelligence devices function on the basis of ‘formal logic’ based programs (or algorithms for short) that tell them to deduce or derive results in series of logical steps. Penrose argues that such an operation can be used to trick the computer easily so that the computer will soon start contradicting its own logic and break down presumably.

Take for example the simple old puzzle:

If the barber shaves all those who do not shave themselves then who shaves the barber?

The simple tit-for-tat reply that pops into your mind now may be: Another barber!

But that answer is too tricky for a computer to arrive at, if it follows logical algorithms, even though a twelve year old can really “see through” the puzzle’s logic. And this is what Gödel’s theorem basically says. Rudy Rucker, in his book Infinity and the Mind: The Science and Philosophy of the Infinite, has simplified Gödel’s Incompleteness Theorem through an excellent example in a stepwise manner.

 

Think over this:

  1. Someone introduces Gödel to a UTM, a machine that is supposed to be a Universal Truth Machine, capable of correctly answering any question at all.
  2. Gödel asks for the program and the circuit design of the Truth Machine. The program may be complicated, but it can only be finitely long. Call the program TMP for Truth Machine Program.
  3. Now, Gödel writes out the following sentence: “The machine constructed on the basis of the TMP will never say that this sentence is true.” Call this sentence G for Gödel. Note that G is equivalent to: “Universal Truth Machine will never say G is true.”
  4. Now Gödel laughs and asks the Truth Machine whether G is true or not.
  5. If the Truth Machine says G is true, then “Universal Truth Machine will never say G is trueis false. If “Universal Truth Machine will never say G is trueis false, then G is false (since G = “Universal Truth Machine will never say G is true). So if the Truth Machine says G is true, then G is in fact false, and UTM has made a false statement. So UTM will never say that G is true, since UTM makes only true statements.
  6. We have established that UTM will never say G is true. So “UTM will never say G is true” is in fact a true statement. So G is true (since G = “UTM will never say G is true”).

And having tricked the Truth Machine, Gödel triumphantly declares: “I know a truth that Truth Machine can never utter,”

 

 

You may have a hunch: “isn’t this a problem of the language we use?”
The answer is NO.
The original incompleteness theorem is mathematically worded. The above simplified version using linguistic conundrums is just an abstraction of the real one. Gödel’s Incompleteness Theorem is a real problem that is faced by artificial intelligence researchers at least on theory level; the fact that we have not been able to attain any sort of complex thinking in machines doesn’t preclude incompleteness theorem from interfering in these matters.

Roger Penrose suggests that the ability of human brain / conscious brain to “go out of the labyrinth of axioms and find the truth outside” is due to the quantum nature of consciousness. He suggests that human consciousness may depend on some new, as yet unknown, quantum physics that has significant role in the neuronal processes of the brain.

More of that in the coming sections of How physics changes the way we look at mind.

The previous article, Why Should Darwinism be Capitalistic?, invited criticism from many of my ‘evolutionist’ friends. Some were against the anti-deterministic underpinnings of the article – they were reluctant to come to terms with the ‘Nature via Nurture’ hypothesis. Others were against my suggestion that Darwinism can be supportive of Socialism rather than capitalism. What most of them complained about was my support of the job and educational reservations to weaker sections of the society.

So here are some clarifications on the issue. These are excerpts from email replies, orkut messages and internet chats. They represent my attempts to detail the:

  • the influence of environment on gene expression (nature via nurture).
  • the use of neo-darwinian evolutionary principles to fight nature’s selection forces.
  • the concept of all-round social upliftment for maximum expression of best genes.
  • the necessity of social reservation and proactive steps to uplift the backward sects of each population.

An analogy to ponder over

Imagine, two pots, with randomly allocated seeds from the same batch. The two plots have equivalent genetic potential. One plot received fertilizer (an environmental condition), the other pot receives no fertilizer. The average height (i.e. intelligence) differences between each pot will be due to environmental differences (fertilizer), however the height differences amongst individual plants within a pot are due to genetic differences (assuming similar conditions throughout the pot).
Which set of plants have a better chance of disseminating their progeny..?
Which set of plants can ensure that most of their “good” genes are transferred to the next generation ?
Progeny of which set of plants are more likely to survive with the better genes ?

Analysis

The gene for higher intellect (henceforth called “smart-gene”) definitely appears in a family/clan/race as a result of mutation and random chance, as evolutionary laws say.

Let me elaborate this:

A child named ‘Z’ in a family of traditional cobblers in India in 800 AD gets a few smart-genes. He has this constant urge to learn, enjoy philosophy or engage in intellectual pursuits. But the strict caste system and social practices of untouchability forbids him from following his heart. Even his family which doesn’t care about education is against his wishes and the boy is compelled to follow his father’s profession, marry somebody from his own caste and spend his life in the way, the strict society wanted him.

His wife, who is from a plain ordinary cobbler family, has no smart-genes. Now our “index” case of smart-gene-mutant is Mr.Z, who has very very small chance of passing his mutant smart-genes to his son or daughter. But still, let us simply suppose the genes were fortunately inherited by Mr.Z’s son. But even then, the son too has very little chance of passing that to the third generation because of the same socioeconomic set up that prevented his father from achieving his own dreams. If he defies the society, the family will soon be destroyed even before a third or fourth generation of children is born.

What if Z’s daughter is the one who inherits the smart-genes? The prospects are worse for a woman in such a rigidly hierarchical and casteist society!!

As long as the same socioeconomic conditions prevail around the family, the smart-genes find less and less chance of inheritance.

Note that there is no inheritance of acquired characters here.
The smart-genes simply rose as a result of “random aimless mutation” as Dawkins often puts it.
The only factor that environment strongly influences, is its chance of being inherited into the subsequent generation.
This situation is a kind of ‘man-made’ negative selection.
The same way we weed out poor yielding poultry or sheep from a farm.
The same way dogs, which are epitomes of servitude and fidelity, were selectively evolved from wolves

Now consider the same situation in a modern liberal Western society like the USA.

The modern Mr. Z, who inherits the smart-genes, takes a scholarship exam, pursues a college education, research in Duke, become a top rated cardiologist in North Carolina and marries the daughter of his research guide. Now his children have because his wife is likely to have the same in her gene pool too. Now, since his wife’s family has a history of intellectual members, the odds of her transmitting the smart-genes to the next generation are also higher. In whichever way you look, Mr. Z’s progeny will have greater chance of inheriting their parents’ smart-genes.

The atmosphere, in which their children grow up, will be stimulation to their genetic potentials. Better nutrition, visuo-spacial challenges of the city and top class education bring the best out of those old smart-genes.

These children, who seek out their own kind (Dawkin’s “green beard effect”) in the society, marry from families of similar or higher intellectual status. The odds of their successive generations becoming smarter improve with every generation.

Note that our Mr. Z of the21st century American city not only faces zero resistance from society but enjoys the fruits of liberty, equality and government’s financial aid in the form of grants, job reservations, scholarships, insurance etc.

This situation is beautifully condensed in the very famous FLYNN EFFECT.

Dr. James Flynn, after doing a meta-analysis of many Western IQ studies done over generations, plotted it against time, and found that average IQ scores increase with generations in the Western societies.

The reason for this is not because the earlier generations had no smart-genes. It’s just that modern western societies are more liberal & conducive for the better expression of these genes to their fullest potentials.

They permit mix up of all kinds, resulting in a global improvement of intellect rather than focal areas of brain development.

That is the most important thing about supporting reservation and other social initiatives to uplift all the sections of population rather than letting natural selection take its toll.

A short verbal ability test administered to about 12,500 adult American Blacks and whites between 1974 and 1994 support this effect of social influence. It clearly shows a narrowing of the IQ differences over recent years – a telltale sign of positive influence on gene expression.

Defying Natural Selection

It may seem strange that in highly competitive meritocratic modern societies, natural selection actually has very little toll on the individual.

If you look deeper, you will see the reason.

With the general improvement in intelligence, human societies progressively have (and will) become altruistic. It’s the selfish gene’s covert strategy to promote the survival of its own kind.

Our hospitals, medical equipments, diagnostic gadgetry, ever expanding array of drugs, humanitarian organizations, peace organizations, trade partnerships etc are towering examples of this altruism and a blatant defiance of Natural Selection.

I am not forgetting the resurgences in imperialist notions especially in recent war histories, but those can be dispensed as the old animal instinct still refusing to go off the skin.

Once the concept of “Nation” and “Nationality” wither away in the future, such notions will have no meaning at all. And by that time hominids, as a species will have something else to fight against…!

Reservation Issue

The whole meaning of reservation, scholarships and grants is to promote the maximal expression of the good genes in these oppressed castes and sects. For that, first of all, there should be some potentially smart genes that can be worked upon to be fully expressible. This means, we can’t expect the whole of those backward castes to ascend to an equal stance with the rest of the society within a very short period of time, simply from affirmative actions. Affirmative actions should essentially be followed by two things if it’s to yield rapid results: # 1) Positive change in social psyche, in accepting them and acknowledging their contributions. # 2) General increase in equality and opportunities for all.

That’s when we can claim that the society has become truly meritocratic.

 

The reservation of seats at the IITs and institutions of excellence is a complex issue. But one thing can be said. Setting apart 20 or 30% seats to the backward classes will not take away any opportunity from the general merit-class. Because, they already are evolutionarily advanced to seek and earn their share. They are already advanced intellectually. What i mean to say is that, economic independence and wealth do not solve the issue at all. The root problem is in the genes, and the remedy requires more than just a few perks to a few individuals. Mixing their genome with the general population will be the ultimate cure, but that would be too fantastic for an expectation in our society.

Spin-offs on Eugenics

I believe, we all have to learn to tolerate the current diversity of our species. We might have to accept the reality of religion-genes, criminality-genes, racism-genes, communism-genes, capitalism-genes, atheism- genes, agnosticism-genes, and what not for that matter. Within our species, each of these has a time and place – to dominate, to stagnate and even to whither away or may be even replaced by totally new genes for totally new things. But the million dollar question is whether our race is ready for that.
Most societies, be it capitalistic or communist, are growing more authoritarian by the day.
That’s a problem with all kinds of eugenics. One might argue for positive eugenics, on the basis that it promotes good qualities of human genome. But as far as our science knows it, most smart-genes are associated with some or the other kind of psychologic / organic defects in the brain – autism and schizophrenia being the ends of a spectrum. Finding a balance in the gene bridge is the biggest problem.

When smartness becomes unlimited, the person becomes a total rebel defying all laws imposed by the society.. When artistic areas of the brain are genetically pushed to its limits, the person experiences regression of the other areas which may even tend towards autism..!! (the autistic idiot savant syndrome is the best example of this kind).

If we promote negative eugenics, by not permitting” diseased” genes from reproducing, that will be an encroachment into the very nature of our life on this planet. But its a re surging concept now. Most genetic screenings are in one or the other way, negative eugenics. Its only a matter of time before the “criminals” in jails will be banned from reproducing…!!

 

Are you saying that we have to go against evolution?

Yes..!
I was exactly trying to say we have to go against evolution in this matter….!
Or else, this race won’t last another millennium…that’s for sure.

Why, because, its the unique ability of the hominids to manipulate nature to meet his needs rather than letting nature manipulate him.

Thats simply what we have been doing ever since we branched out from the primate ancestors…Just look around and we will see only those things that man has built, invented or designed, to suit his needs, to help alleviate his toil, to ease his life, to bring out the maximum of his potential…!

Our hospitals defy the very basics of natural selection by differential extinction,
Our prenatal checkups do the same
Our geriatric centers do the same
Our schools do the same
Our railway, airlines, banks, bridges and roads, our space stations, satellites, rockets, hydel power stations, nuclear reactors….you name it…Everything helps man in one way or the other in defying Nature’s forces, and saving him from being deselected..!

So why don’t we extend this privilege to all classes of people in every population..?

Darwinian and neo-Darwinian ideas of natural selection, differential extinction and adaptive evolution have traditionally been linked to capitalistic views of “survival of the fittest”. As decades passed by, people including the scientific community at large began seeing Darwinian Laws of evolution (its not just a theory any more) as a justification for the greed, consumerism, “hire-fire” notions and at times, the imperialistic overtones of right winged capitalism and market rule.

 

There are no evidences to show that Darwin himself took his theories to this extent. But the synonymity between capitalistic notions of “might is right” has been increasingly supported by many studies on genetic determinism. Now, anything from racial superiority to anti-reservation campaign is justified by these contorted interpretations of laws of evolution. Even though Galton’s eugenics failed miserably in its original form (negative eugenics), it is coming back in many new disguises from white supremacy to culture-war theories – a poetic justice to history, I should say.

 

Are the laws of evolution as anti-socialistic as is viewed to be?

 

 

It is an undisputed fact that selection process of nature is highly merit-based and extinction awaits anything that is maladapted to its environs.

 

 

 

 

What helps adaptation?
Phenotypic expressions of genes on an individual basis and in combinations.

This is where determinists hijack the theory.
First, every trait from music and arts to adoption of a religious belief becomes the responsibility of genes. And if genes are the basis of selection, then there has to be superiority and inferiority among genes, as there are superior and inferior qualities, they say. Any animal that inherits undesirable or malfunctioning genes, as a rule, becomes inferior by their standards. Some take it a little further and attribute every trait they hate, on genes.

 

Thus ‘black skin’ becomes an undesired trait; lower scores on IQ tests become an undesired trait; poor performance in economic issues becomes an undesirable trait; inability of the brain to concur with societal laws becomes undesirable…the hate-list soon grows to include anything from eating habits, ideologies, cultures to (these days) even religious beliefs!

 

It is not surprising that the Nature versus Nurture debate now revolves around this controversy.

 

What these people and scientists don’t see is the context in which “survival of the fittest” is applicable. Homosapiens as a species needs to compete with everything around, including other life forms as well as nature for survival and he is doing the job remarkably well. But within the species are we supposed to keep this rule alive? Mammals, as a group, have evolved to the present state facing stiff competition from many other groups – mostly reptiles. And it is undoubtedly, societal cooperation that has helped them the most in the fight.

Hominids are no different…

 

 

In fact, it is ‘intra-specific cooperation’ that has been key in the development of many humanly attributable qualities – like language, script, technology and science; this is true for every social animal. There is ample evidence to show that all those ‘human’ qualities that we boast about, are result of nurturing the right kind of genes. The recent expositions regarding the environmental influences on psychosocial development and human intelligence points to this direction.

 

The laws of evolution, far from being the Trojan horse for social injustice, are actually excellent tools for social-engineering in every positive sense of the word. To see this, you just have to consider the whole of humanity – rather hominids – as one large group pitched against the forces of nature. The importance of universal nurturing of advantageous traits thru global initiatives will thus become clearer in the new light.

 

This essentially will mean that leaving various sects of the society to its own fate thru unrestricted finance capital and free market economy is not only against the spirit of human evolution but also the greatest blunder that man can commit, considering the unique ability of his brain to stand up against his genes. And that is where Socialism marries Darwinism.

 

Let me conclude quoting Dawkins, the messiah of ‘selfish gene’, who wrote in a rebuttal of Lewontin, Rose & Kamin:

 

…. it is perfectly possible to hold that genes exert a statistical influence on human behaviour while at the same time believing that this influence can be modified, overridden or reversed by other influences…. human sexuality has evolved from natural selection just the same way any animal trait evolved…this means that there have been genes influencing sexual desire just as genes ever influence anything. Yet ‘genetic determinists’ have no trouble holding back their sexual desires when it is socially necessary to do so. What is dualist about that? Obviously nothing…We, that is our brains, are separate and independent enough from our genes to rebel against them…we do so in a small way when we use contraception. There is no reason why we should not rebel in a large way too…

[The Selfish Gene : 1989 OUP edition End notes to Chapter 11]

 

 

Ever since its discovery, Tyrannosaurusrex, paleontologists and laypeople have been mesmerized by the sheer enormity of this giant carnivore. Every time a new discovery or debate concerning T-rex pops up, it attracts fans from every field; very few historical things have enjoyed such phenomenal popularity – the Titanic, the Pyramids etc are a few on the list.

T-rex has been bestowed with the titles of the most ferocious animal that ever walked the earth and the largest predator on land. But is the story of T-rex, a bit over-hyped? Is it worth these titles any longer?

 

New evidences on the predatory behaviour of dinosaurs are coming up, thanks to the bionic technology that uses computer simulations merging paleontological findings with physics of animal body.

Why is this tyrant-lizard so popular?

 

The first Tyrannosaurus rex fossil was discovered by Barnum Brown in 1902. By the time T- rex was named by Henry Osborn in 1905, news about this strange and seemingly formidable “predator” was out and names that captured the popular fantasy of a “dragon” like ferocious lizard became a necessity. (Dynamosaurus imperiosus, was a synonymous name Osborn later suggested for Tyrannosaurus !). T-rex soon was seen as the materialization of the mythological dragon; the ultimate killing machine. And Hollywood was quick enough to take this fantasy to its extremes, Jurassic Park being the ultimate reference.
After all that popular appeal and fan-following, its now become difficult for both scientists and the masses to see T-rex as a huge, awkward, lumbering beast that waddled out of the bushes to pick off the remains of a carcass.

 

Not the largest predator.

T-rex now has only the fourth position with regard to size among predatory land animals, Spinosaurus being the first, Giganotosaurus being the second and Carcharodontosaurus being the third. Discussions and comparisons on the predatory capabilities of these four dinos had heated up the paleobiology circles recently; the debate is still on. Spinosaur, as depicted almost correctly in Jurassic park III, is currently the largest carnivore. But compared to T-rex, the other three dinos had weaker build and teeth designed for slicing up flesh. T-rex brain case is larger, has solid teeth to crush bones, and supposedly has a better build.

 

These points gave T-rex an edge over the others and T-rex fans finally had some reason for consolation.

 

Stiff spine, sharp senses : hyena or lion ?

 

Then came the expositions about the spine. A US team has used detailed computer models to work out the weight of a typical “king of the dinosaurs”, and determine how it ran and turned. The results indicate a 6 to 8-tonne T. rex was unlikely to have topped 40km/h (25mph) and would take a couple of seconds to swivel 45 degrees. The study indicates the animal would have changed direction incredibly slowly because of its massive inertia, taking more than two seconds to make a quarter-turn. The species certainly could not have pirouetted rapidly on one leg, as popular illustrations have sometimes pictured it, and other large dinosaurs, doing. The more agile prey would have given the slip to a marauding T. rex quite easily, it seems.
A massive blow to the “predatory” nature!

 

But that wasn’t the end of controversial findings. Dr. Lawrence Witmer, from Ohio University, used the medical scanning technique of computed tomography (CT scanning) to reconstruct the shape of the animal’s brain, including its inner ear, which is involved not only in hearing but also body-balance.

 

T. rex has the inner ear comparable to that of a much smaller, very agile animal. It had a heightened sense of equilibrium and balance and employed rapid turning movements of its eyes and head to track its prey.

 

But Dr. Jack Horner, the leading scientist who supports the “Scavenger T-rex” theory, carried out microscopic analysis of the dinosaur’s vertebrae. His team found tissue remnants related to the animal’s nuchal ligament, which provides passive support for the head and neck. The study also points at how rigid it was from the neck all the way back to the tail.

 

The teeth that crush bones are typical of a scavenger… the puny fore-legs are very unlikely evolutionary weapons for a hunter…the extraordinarily latge olfactory lobes of the T-rex brain is typical of a scavenger that sniffed for its food…the massive hind legs are those of a walker, not a sprinter….thus goes the evidence against the “hunter T-rex” theory.

 

We like our T. rex to be the monster from hell, threatening to rip the heads off poor, screaming kids when their jeep gets stuck in Jurassic Park. But evidences are throwing light on a scavenger-lizard now, claims Dr Jack Horner.

 

The simplest way to come to terms with this new reality is to compare an ideal predator like the Velociraptor or the Cheetah with T-rex and see the voids for yourself.

 

“We want people to do what scientists do, which is to take all that in, think about it, and then come to a conclusion….my own view is that the truth lies somewhere in the middle. We know it wasn’t a fast-running creature like a cheetah, but I certainly think it would have been capable of killing a small, old or weak animal.” says Horner.

 

The sudden feeling of vague familiarity about certain scenes or things of life is a common phenomenon we might all have experienced one time or the other. Many of them were dream-like experiences, while some were so vivid; we almost thought it was a replay of the past.

The term “déjà vu” is believed to have been used first in 1876 by French physician Émile Boirac. Each episode last a few seconds only and is much common for Younger people to have these dream-states more often than older adults, yet people of all ages experience déjà vu, especially when they are stressed. There is a reverse of déjà vu, called jamais vu. Here, a familiar person or place is rejected as having never seen before.Many mysteries cloud this curious play of brain chemistry and many of them give rise to beliefs in rebirth, telepathy and clairvoyance. But is this strange feeling of familiarity really a message traveling thru time and space, from the light cone of our past? Or is it just some unconsciously managed memory trace that is peeking up at a second stimulus thru the same neural pathway?

Science has been tracking this question for many years but the stumbling block in investigating the phenomenon is the problem of recreating it in labs.

The Freudian psychoanalysts call déjà vu a replay of suppressed memories. They call it paramnesia. The original event was somehow linked to distress and was being suppressed from conscious recognition, no longer accessible to memory, they say. Temporal lobe epilepsy patients have been thought as good candidates, but their memories lack the true quality of déjà vu – the subject’s disbelief in the memory!

Dr. Vernon M. Neppe[/b] , the Director of the Pacific Neuropsychiatry Institute in Seattle, empirically defined the term déjà vu as: [u]

“any subjectively inappropriate impression of familiarity of a present experience with an undefined past.”[/u]

(His book titled [i]The psychology of Déjà vu: Have I been here before?[/i] has detailed out a long list of déjà vu presentations long back in the 1980s.)

In déjà vu, the subjective feeling of “replay of past” is imminently followed by a feeling of disbelief and rejection of the memory trace, as is widely documented. The act of seeing or hearing also does evoke a feeling of familiarity. It doesn’t pertain just to the memory alone. These qualities are absent in epileptic patients’ recollections and in drug-induced hallucinations. In such cases, the patient or the subject strongly “believes” in these traces of replayed “memory”. A similar phenomenon is seen in schizophrenics too (‘false recognition’). Hence many scientists believe that there should be a “non-epileptic” theory for deja vu that will encompass al the attributes of the phenomenon.

 

New light on an old problem

Robert Efron, in 1963 suggested the delayed vision theory. He stated that it is possible that sometimes the blending of information into the temporal lobe might not synchronize well and this may result in the deja vu episodes. Words flashed too rapidly to subjects without giving time for the conscious brain to register them were later identified as familiar by the same subjects in the pioneering experiments of Dr. Larry Jacoby in 1989. Recent simulated studies on attention and priming for attention have brought out certain correlations between gaps in attention and feelings of familiarity as in déjà vu. There are also reliable correlations between déjà vu and stress/fatigue as well as mood swings. It seems that whereas déjà vu may be triggered during times of peak tension when one is overly alert, it may be even more likely when one becomes tired and attention starts to wane. Alan Brown of the Southern Methodist Univ and Elizabeth Marsh at Duke University, ran a few tests on a group of students; based on the idea that deja vu’s originate in subliminal suggestion. They support the the diverted attention theory.

According to the theory, people sometimes see things twice in quick succession: the first time superficially or peripherally; the second time with full awareness. You might glance at a building while talking on a cell phone, for instance, and not really register it, then give it a second look a little while later after you get off the phone. You might not remember the first glance, but your brain has registered it subliminally, so the second glance may seem oddly familiar (see Dr.Brown’s new book [i]The Déjà Vu Experience[/i])

Temporal lobe – seat of Deja vu

Open brain surgery stimulations of déjà vu in temporal lobe has been done from the time of Dr. Penfield the latest being that of Dr.Bancaud.These expositions are being investigated with greater fervor, ever since the Alison R. Preston and John D.E. Gabrieli paper on the role of hippocampus as a scrap book of the brain, has come out.

….the relational/familiarity distinction predicts that patients with focal hippocampal damage would be selectively or disproportionately impaired on associative recognition, but exhibit intact or less impaired performance on single-item recognition. However, patients with selective hippocampal damage were equally impaired on the single-item and associative recognition tasks….. results suggest that the hippocampal formation contributes similarly to declarative memory tasks that require relational or familiarity processing…. the para-hippocampal gyrus differentiates between familiar and unfamiliar stimuli – and does so without having to retrieve a concrete episode from our memories.

The excitement is inexplicable, as the research has opened new ways to understand how we create a world of our own around us rather than fit ourselves into the world around. And that’s were evolutionary psychology starts taking up the issue.

 

A new bird from the family of Oviraptors (the egg-stealers among dinos) has been discovered by paleontologist Xing Xu and team of the Beijing’s Institute of Vertebrate Paleontology and Paleoanthropology in the Gobi Desert in north-central China.

 

Initially thought have belonged to the T-rex family (see artists scale- drawing), this giant “bird of prey” is now grouped under the family of smaller raptors – an unusual reunion.!

 

The finding complicates the evolutionary descent of birds from dinosaurs. Progressively from within advanced theropods as you come to birds, their size gets smaller and smaller. But after some species originate and spring off the bird line, you get secondary gigantism.

“Big size has some advantages such as having fewer predators and having more food resources that are unavailable for small animals,” Xu notes. He is joined by Thomas R. Holtz Jr., a vertebrate paleontologist at the University of Maryland at College Park who adds “ Gigantoraptors grew muc h faster and reached adulthood more quickly than did tyrannosaurs. There was an incentive [for such a creature] to get big really soon” Size is certainly a defense. And there is ample evidence to believe that these giant-birds lived at a time when T-rex ruled the earth.

The length and proportions of Gigantoraptor’s leg bones hint at another of the dinosaur’s survival skills – its speed. The bird-like femur suggests it would have been among the fastest dinosaurs of its body size.

It also is not clear whether the creature was feathered, though Xu speculates it was like most other animals in its lineage. If so, it would be by far the largest known feathered animal of all time.

One of the fundamental problems of studying the phenomenon of Consciousness is in defining it objectively. To define it, one has to make a replicable model of consciousness, using some universal aspect of animal behavior that can be measured independent of the internal state of the individual’s brain in a lab setting.

Neuroscientists have, long ago, concurred on the usefulness of measuring CONFIDENCE as a function of consciousness.

What is this?

Let me explain a bit:

A subject has to see the direction of movement of a blinking dot on a screen first. After seeing, he has to decide for sure which direction the movement occurred. Since the perception of movement and the decision on its direction can be “unconscious” as far as the brain is concerned. So, to make this unconscious perception a conscious and purposeful one, the subject is asked to make a finite choice – a sort of betting – on the direction of the motion of the blotch on the screen by means of selecting a number. For example, 1 to indicate pure guessing, 2 for some uncertainty and 3 for complete certainty. This procedure assumes that when the subject has little awareness of the dots’ direction of motion his confidence is low, whereas if he clearly “saw” the motion, his confidence is high.

 

Navindra Persaud of the University of Toronto and Peter McLeod and Alan Cowey of Oxford University took this to the next step, by adding a bit of “real” gambling (Nature Neuroscience January 2007). In their version, subjects first make a decision regarding whether they’ve perceived something and then must gamble either a small or a large amount of money on their confidence in this decision.

 

Their first experiment involved a patient code-named GY. This man has a rare acquired pathology called “blindsight”. His brain areas involved in the sense of vision were damaged in an accident. Now, his eyes “see” the blotch on the screen but since the visual areas of the brain never receive signals from the eyes, he doesn’t have the “conscious” feeling of having seen the blotch. But physiologically speaking, he does “see” the blotches. The phenomenon of “blindsight” gives scientists an opportunity to test the subjective “unconscious” feelings and make the patient convert them into “conscious” feelings. When asked to indicate the presence or absence of a faint, small grating on a computer screen, he does so correctly in 70 % of all trials, which is far above chance (50 %). Yet he fails to convert this superior performance into money when betting; he places a high bet on only about half (48 %) of his correct choices. When GY is consciously aware of the stimulus, he wagers high, much as we all would. His gambling thus seems to reflect his conscious awareness of his belief that he saw the blotch rather than his actual (unconscious) detection of the stimulus, suggesting that Gambling may provide a means to measure awareness.

 

The second experiment involves an artificial grammar task. In this task participants learn a small number of short letter sequences. They are then told that the sequences obeyed a simple rule (like for example, that every “x” is always followed by an “a”). But they are not told what the rule is. When shown a new sequence, subjects mostly determine correctly whether the new sequence follows the unknown rule. Yet very rarely can the subjects decipher why they believe a sequence does or does not obey the rule. The overall rate of correct classification is 81%.Yet subjects do not convert performance into money. High bets follow a correct choice 45 % of the time and follow a false choice 32 % of the time. In short, the subjects are usually right about whether the sequence follows the rule, but they lack enough confidence to bet on it.In the final experiment, the Iowa gambling task subjects pick the top card from one of four decks. Each card wins or loses the subject a certain amount of money. Two of the four decks have a net positive yield and two a negative yield, which the subjects don’t know. Subjects place a low or a high bet on the chosen card before it is revealed and lose or win accordingly. The outcome of the experiment is that they usually turn over at least 30 cards on those decks before they gain the confidence to bet aggressively on the results. That is, they wait for a certain time before they can believe in their own knowledge of the nature of the decks.

But whenever the subjects were questioned about their knowledge of the “rule” of the card game, the subjects increasingly started aggressive betting. The questioning gave them a way to ponder on their own knowledge and how it could be turned advantageous. This demonstrates that if subjects learn to trust their gut they can do better.

The wagering techniques used by Persaud, McLeod and Cowey rely on people’s instinct for reaping a profit. This method is a far better one in reliably measuring consciousness b’coz it doesn’t alter the instinct. Rather, it simply assesses how one converts the unconscious perception into a purposeful, conscious, action.