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Are there two types of cognition?

J. Evans’ 2008 paper reviews a number of proposed dual-processing descriptions of cognition. (see citation). He finds some stable divisions in the theories but a number of conflicting ones also. Calling the dual processing system 1 and system 2 appears to him to give a mistaken impression of how cognition works; he feels that processes (not locations, contents, parallel systems etc.) is the key difference and uses the terms type 1 and type 2.

A core type 2 is fairly easy to define – slow, sequential, limited capacity, associated with working memory and conscious experience. Around this core, various theories diverge. Type 1 seems almost impossible to define at present with much agreement, except that it is not type 2. It may not be (probably isn’t) a single type of process. I look for types 1a, 1b etc. in future.

Here is part of the concluding discussion in the paper:

Although dual-process theories have been around in cognitive and social psychology for 30 years and more, it is only within the past 10 years or so that the terms System 1 and System 2 have come into common use. … However, close inspection of the evidence suggests that generic dual-system theory is currently oversimplified and misleading. In particular, (a) it is not possible coherently to link together all the attributes associated with Systems 1 and 2 … and (b) there are at least two quite distinct forms of dual-process theory to be found in these various literatures that can not readily be mapped on to each other. We might be better off talking about type 1 and type 2 processes since all theories seem to contrast fast, automatic, or unconscious processes with those that are slow, effortful, and conscious. However, it would then be helpful to have some clear basis for this distinction. … My suggestion is that type 2 processes are those that require access to a single, capacity-limited central working memory resource, while type 1 processes do not require such access. This implies that the core features of type 2 processes are that they are slow, sequential, and capacity limited. The last feature implies also that their functioning will correlate with individual differences in cognitive capacity and be disrupted by concurrent working memory load. …

However, other proposed features of System 2 in the generic theory do not immediately follow from this definition of type 2 processes, for example, the proposal that such processes are uniquely human or associated with decontextualized thought or rule-based reasoning.

The problem with this distinction is that type 1 processes then simply refer to any processes in the mind that can operate automatically without occupying working memory space. As already indicated, there are a number of different kinds of such implicit processes. We may have innate cognitive modules with encapsulated processes for perception, attention, language processing, and so on. We appear to have an associative learning system that implicitly acquires knowledge of the world in a form similar to weights in neural networks; the knowledge cannot be called to mind as explicit knowledge, but it can directly affect our behavior. We have habitual and automated behavior patterns that once required conscious type 2 effort but seem to have become type 1 with practice and experience. We also have powerful pragmatic processes that rapidly identify and retrieve explicit knowledge for conscious processing. Type 2 processing requires supporting type 1 processes to supply a continuous stream of relevant content into working memory. If there are indeed multiple kinds of type 1 processes, then it is to be expected that psychologists will have developed different kinds of dual-process theories, which seems to be the case. …

In short, my conclusion is that although dual-process theories enjoy good empirical support in a number of fields of psychology, the superficially attractive notion that they are all related to the same underlying two systems of cognition is probably mistaken, at least in the way that Systems 1 and 2 are being defined in the current literatures. For example, it is almost certainly wrong to think of System 1 as one system, all of which is old and shared with other animals. Equally, it is probably a mistake to think of System 2 as the conscious mind, all of whose processes are slow and sequential. If there is a second system, distinctively human, involving working memory and neurologically distinct structures, it does not follow that all of its workings are conscious and controlled. It is perfectly possible that one system operates entirely with type 1 processes and that the other includes a mixture of type 1 and type 2 processes, the latter being linked to the use of working memory, which this system uses - among other resources. Such a proposal could resolve the conflict between evidence for dual systems on the one hand with the proposals of different dual-process theorists on the other.

Dual-processes of cognition seems the wrong description of what is likely to be a very complex mixture of types and combinations of types. Again reality refuses to be neatly divided into just two parts.

 

ResearchBlogging.org

J. Evans (2008). Dual-Processing Accounts of Reasoning, Judgement, and Social Cognition Annu. Rev. Psychol. (59), 255-278

The new way to view cognition

This year’s Edge question is “What is your favorite deep, elegant, or beautiful explanation?”. If you want to read all the answers go (here). Simone Schnall has answered with embodied cognition and its solving of the questions of meaning and grounding.

Philosophers and psychologists grappled with a fundamental question for quite some time: How does the brain derive meaning? If thoughts consist of the manipulation of abstract symbols, just like computers are processing 0s and 1s, then how are such abstract symbols translated into meaningful cognitive representations? This so-called “symbol grounding problem” has now been largely overcome because many findings from cognitive science suggest that the brain does not really translate incoming information into abstract symbols in the first place. Instead, sensory and perceptual inputs from every-day experience are taken in their modality-specific form, and they provide the building blocks of thoughts. …following the cognitive revolution in the 1950ies psychology treated the computer as the most appropriate model to study the mind. Now we know that a brain does not work like a computer. Its job is not to store or process information; instead, its job is to drive and control the actions of the brain’s large appendage, the body. A new revolution is taking shape, considered by some to bring an end to cognitivism, and giving way to a transformed kind of cognitive science, namely an embodied cognitive science. … The basic claim is that the mind thinks in embodied metaphors. … But it does not stop here; there is also a reverse pathway: Because thinking is for doing, many bodily processes feed back into the mind to drive action.

She uses the metaphor of verticality (up/down) and morality (good/bad) to illustrate how the metaphors work.

The growing recognition that embodied metaphors provide one common language of the mind has lead to fundamentally different ways of studying how people think. For example, under the assumption that the mind functions like a computer psychologists hoped to figure out how people think by observing how they play chess, or memorize lists of random words. From an embodied perspective it is evident that such scientific attempts were hopelessly doomed to fail. Instead, it is increasingly clear that cognitive operations of any creature, including humans, have to solve certain adaptive challenges of the physical environment. In the process, embodied metaphors are the building blocks of perception, cognition, and action. It doesn’t get much more simple and elegant than that.

Of course, there are many people who have not accepted that the computer model of the brain is finished. They point out that computers can simulate brains (or more or less anything). But there is a difference between being able to simulate the weather in order to predict it and treating a computer as the model of how the weather engines work. The same applies to brains. Computers are very useful tools for studying various simulations of the brain, but the brain is not a computer.

About the claustrum

It is that time of year – time for the Edge question. When I see this on the menu it gives me a little tingle. This year’s question is “What is your favorite deep, elegant, or beautiful explanation?”. If you want to read all the answers go (here).

 

Here is part of V. Ramachandran piece on Crick’s many explanations. This bit is about his claustrum idea.

In biology, knowledge of structure often leads to knowledge of function—one need look no further than the whole of medical history. … I believe there are similar correlations between brain structure and mind function, between neurons and consciousness. I am stating the obvious here only because there are some philosophers, called “new mysterians,” who believe the opposite. … After his triumph with heredity, Crick turned to what he called the “second great riddle” in biology—consciousness. There were many skeptics.

Crick did not, in my opinion, succeed in solving consciousness (whatever that might mean). Nonetheless, I believe he was headed in the right direction. He had been richly rewarded earlier in his career for grasping the analogy between biological complementarities, the notion that the structural logic of the molecule dictates the functional logic of heredity. Given his phenomenal success using the strategy of structure-function analogy, it is hardly surprising that he imported the same style of thinking to study consciousness. He and his colleague Christoff Koch did so by focusing on a relatively obscure structure called the claustrum.

The claustrum is a thin sheet of cells underlying the insular cortex of the brain, one on each hemisphere. It is histologically more homogeneous than most brain structures, and intriguingly, unlike most brain structures (which send and receive signals to and from a small subset of other structures), the claustrum is reciprocally connected with almost every cortical region. The structural and functional streamlining might ensure that, when waves of information come through the claustrum, its neurons will be exquisitely sensitive to the timing of the inputs.

What does this have to do with consciousness? Instead of focusing on pedantic philosophical issues, Crick and Koch began with their naïve intuitions. “Consciousness” has many attributes—continuity in time, a sense of agency or free will, recursiveness or “self-awareness,” etc. But one attribute that stands out is subjective unity: you experience all your diverse sense impressions, thoughts, willed actions and memories as being a unity—not jittery or fragmented. This attribute of consciousness, with the accompanying sense of the immediate “present” or “here and now,” is so obvious that we don’t usually think about it; we regard it as axiomatic.

So a central feature of consciousness is its unity—and here is a brain structure that sends and receives signals to and from practically all other brain structures, including the right parietal (involved in polysensory convergence and embodiment) and anterior cingulate (involved in the experience of “free will”). Thus the claustrum seems to unify everything anatomically, and consciousness does so mentally. Crick and Koch recognized that this may not be a coincidence: the claustrum may be central to consciousness; indeed it may embody the idea of the ” Cartesian theater” that’s taboo among philosophers—or is at least the conductor of the orchestra. This is this kind of childlike reasoning that often leads to great discoveries. Obviously, such analogies don’t replace rigorous science, but they’re a good place to start. Crick and Koch may be right or wrong, but their idea is elegant. If they’re right, they’ve paved the way to solving one of the great mysteries of biology. Even if they’re wrong, students entering the field would do well to emulate their style. Crick has been right too often to ignore.

I visited him at his home in La Jolla in July of 2004. He saw me to the door as I was leaving and as we parted, gave me a sly, conspiratorial wink: “I think it’s the claustrum, Rama; it’s where the secret is.” A week later he passed away.

 

The general notion today is that consciousness is not localized in a particular place and is spread across the cortex, but given Crick’s record and methodology it might be a good idea to look at the claustrum.

Two sides of synchrony

Humans often engage in synchrony (as do mating birds and other animals). We sing, chant, dance, march together. We have special work songs to coordinate movement. Synchrony is enjoyable. It also takes some of our autonomy and gives it to the others that we are in sync with. This can be good and bad depending on the group and its aims. And it seems to have a very powerful effect on consciousness - almost like a high.

 

We can see the usefulness of work songs. The coordination make everyone’s efforts more effective. There is a feeling that you are not pulling alone and that whatever your effort is, it is not being wasted. I would guess that anyone not putting in effort when it was rhythmic would be easy to spot and so the synchrony might also be an enforcer of cooperation.

 

Wiltermuth and Heath in their 2009 paper showed that synchronous movement or singing does indeed enhance a group identity and produced behaviour that was more group oriented even at the individuals expense.

Taken together, these studies suggest that acting in synchrony with others can lead people to cooperate with group members. While the studies do not eliminate the possibility that muscular bonding and collective effervescence may, under the right conditions, strengthen the effects of synchrony on cooperation, our results show that synchronous action need not entail muscular bonding or instill collective effervescence to create a willingness to cooperate. Our results suggest that cultural practices involving synchrony (e.g., music, dance, and marching) may enable groups to mitigate the free-rider problem and more successfully coordinate in taking potentially costly social action. Synchrony rituals may have therefore endowed some cultural groups with an advantage in societal evolution, leading some groups to survive where others have failed .

 

Cooperating in positive group activities is one side but the other negative side is the rejection of people outside the group. Synchrony is used in war dances and modern military displays. While sports teams are competing on the field, their fans are competing in the stands in shows of synchrony.

 

Wiltermuth in his 2012 paper showed the aggressive results of synchrony. His studies indicate that synchronous activities may be used to influence leader-follower relations. Marching and chanting are used rallies to influence people across the world and the centuries. Think Hitler.

An experiment demonstrates that cultural practices involving physical synchrony can emotionally bind people together, making those people more likely to comply with others’ requests to engage in aggressive behavior. Participants who acted in synchrony with a confederate were more likely than were participants in the asynchronous and control conditions to comply with the confederate’s request to administer a noise blast to another group of participants. Increased feelings of emotional connection with the confederate mediated the relationship between synchrony and heightened compliance with the request to engage in aggressive behavior.

 

Do we have any protection against being lead astray by synchrony? Maybe we have. Many people have a natural loner rather than joiner character which makes them suspicious of group displays. The first part of getting in sync is to mimic others. It seems we naturally mimic those we are with and do not realize we do it. But only if we share goals with the others. That is a nice little safety catch!

 

Ondobaka and others showed this in their 2011 paper.

Observing the movements of another person influences the observer’s intention to execute similar movements. However, little is known about how action intentions formed prior to movement planning influence this effect. In the experiment reported here, we manipulated the congruency of movement intentions and action intentions in a pair of jointly acting individuals (i.e., a participant paired with a confederate coactor) and investigated how congruency influenced performance. Overall, participants initiated actions faster when they had the same action intention as the coactor (i.e., when participants and the coactor were pursuing the same conceptual goal). Participants’ responses were also faster when their and the coactor’s movement intentions were directed to the same spatial location, but only when participants had the same action intention as the coactor. These findings suggest that observers use the same representation to implement their own action intentions that they use to infer other people’s action intentions and also that a dynamic, multitiered intentional mechanism is involved in the processing of other people’s actions.

 

This reminds me a bit of oxytocin – it creates empathy to the in-group and increasing xenophobia for the out-group. It is great in the family and small community but a problem in the bigger world.

 

So when you become consciously aware of that nice, warm part-of-group feeling, take a moment to look at the group’s aims, before joining in the song and dance.

 

ResearchBlogging.org

Wiltermuth, S., & Heath, C. (2009). Synchrony and Cooperation Psychological Science, 20 (1), 1-5 DOI: 10.1111/j.1467-9280.2008.02253.x

Ondobaka, S., de Lange, F., Newman-Norlund, R., Wiemers, M., & Bekkering, H. (2011). Interplay Between Action and Movement Intentions During Social Interaction Psychological Science, 23 (1), 30-35 DOI: 10.1177/0956797611424163

Wiltermuth, S. (2012). Synchronous activity boosts compliance with requests to aggress Journal of Experimental Social Psychology, 48 (1), 453-456 DOI: 10.1016/j.jesp.2011.10.007

Skull shape changes are not independent

ScienceDaily had an item (here) on research (Martínez-Abadías and others, Pervasive genetic integration directs the evolution of human skull shape. Evolution, 2011) showing that human history may have intertwined evolutionary pressures rather than sequential ones.

They worked with a unique set of skulls that could be matched with good genealogical data to test various theories of skull shape determinants. In particular they looked at changes that were important in human evolution: the shift of the foramen magnum where the spinal cord enters the skull associated with upright walking, the retraction of the face associated with chewing soft food (cooked using of fire?) and vocalizing, and the rounding expansion of the top of the skull associated from increased neocortex mass leading to tool making, language, general smarts. These have been thought to have evolved independently.

(The researchers) found that, rather than being separate evolutionary events, changes in one part of the brain would facilitate and even drive changes in the other parts. “We found that genetic variation in the skull is highly integrated, so if selection were to favour a shape change in a particular part of the skull, there would be a response involving changes throughout the skull,” said Dr Chris Klingenberg.

Previously, environmental pressure were postulated separately for each of these three changes. This research points to a more fluid evolution where specific pressures might not be needed for some changes or where several less powerful pressures might work together.

Here is their abstract:

It has long been unclear whether the different derived cranial traits of modern humans evolved independently in response to separate selection pressures or whether they resulted from the inherent morphological integration throughout the skull. In a novel approach to this issue, we combine evolutionary quantitative genetics and geometric morphometrics to analyze genetic and phenotypic integration in human skull shape. We measured human skulls in the ossuary of Hallstatt (Austria), which offer a unique opportunity because they are associated with genealogical data. Our results indicate pronounced covariation of traits throughout the skull. Separate simulations of selection for localized shape changes corresponding to some of the principal derived characters of modern human skulls produced outcomes that were similar to each other and involved a joint response in all of these traits. The data for both genetic and phenotypic shape variation were not consistent with the hypothesis that the face, cranial base, and cranial vault are completely independent modules but relatively strongly integrated structures. These results indicate pervasive integration in the human skull and suggest a reinterpretation of the selective scenario for human evolution where the origin of any one of the derived characters may have facilitated the evolution of the others.

What does this have to do with consciousness? Maybe it has nothing to do with it, but it does remove the need for specific causes for every difference between human and other great ape brain proportions.

 

the other way around

Some ideas can just be backwards. Take the famous ‘I think therefore I am’. There are not that many people who actually question whether or not they exist. The idea that I might doubt my existence but not my thought is somewhat odd. The implication is that introspection has more reality than reality itself. The opposite idea is that reality is really real and introspection is an inaccurate, sometimes illusionary, ‘copy’ of it. Now, Descartes was a great thinker for his time but a lot has happened since 1637. Science started only a few years before. Science has been studying the physical world for much of the intervening time making reality much more understandable and, as a result, dualism has fallen out of fashion. Well, that Descartes type of dualism anyway. But we go on dividing things in two.

There was a time when it was reasonable to assume that what we now call consciousness was thought and all of thought. It is what we experience and all other mental activity is inferred or deduced. There seemed one mind and it was the mind we had experience of. But deduction and inference has been going on for some time and now it appears that most thought is carried on without coming to conscious awareness. It would be reasonable to assume that there is only one mind and we are aware of part of what that mind does. We are not longer forced to either the naïve version of only conscious thought or the dualist version of two minds (conscious and unconscious) with two types of thought. We do not actually know how the brain functions – it is possible that there are a number of different thought processes, 6 or 7. Why 2? Personally, I would bet money on there being so much integration that it will be seen as one process in time.

Then we have gone on and divided animals into humans and other animals; an extremely old divide. But over time, the more we know about biology, the more that humans fit right into animals of the higher ape variety. The things that defined us as very different have fallen away one by one. Other animals use tools, they deceive, they make plans, time travel, have theories of mind, similar emotions and on and on. All that is left it seems is language and even that is not fully secure with parrots, dogs, elephants, dolphins and so on having traces of something close to the line. In order to preserve the human position as somehow very different from animals we have made a taboo of anthropomorphism. We feel we must resist any assumption that animals are like us until the we are forced to give up by evidence. In biochemistry, biophysics, physiology, anatomy we are animals with very few distinguishing features (no more than any other animal). Why should we assume that our psychology and behavior is extremely different, a difference of kind rather than degree.

I am getting very suspicious of anything that comes in exactly two distinct varieties. If it turns out to be a spectrum with two names for the extremes – OK. But two distinct types – I suspect that someone likes to have a duality here and I need to be convinced.

A look at the dogma

The authors of a new paper (citation below) have doubts about some well known ‘facts’ in neuroscience. I have to admit I assumed that the numbers were backed by evidence. I may have used these numbers in posts and so I feel bound to share the doubts with readers. Here is the abstract:

Owing to methodological shortcomings and a certain conservatism that consolidates wrong assumptions in the literature, some dogmas have become established and reproduced in papers and textbooks, derived from quantitative features of the brain. The first dogma states that the cerebral cortex is the pinnacle of brain evolution – based on the observations that its volume is greater in more ‘intelligent’ species, and that cortical surface area grows more than any other brain region, to reach the largest proportion in higher primates and humans. The second dogma claims that the human brain contains 100 billion neurons, plus 10-fold more glial cells. These round numbers have become widely adopted, although data provided by different authors have led to a broad range of 75– 125 billion neurons in the whole brain. The third dogma derives from the second, and states that our brain is structurally special, an outlier as compared with other primates. Being so large and convoluted, it is a special construct of nature, unrelated to evolutionary scaling. Finally, the fourth dogma appeared as a tentative explanation for the considerable growth of the brain throughout development and evolution – being modular in structure, the brain (and particularly the cerebral cortex) grows by tangential addition of modules that are uniform in neuronal composition. In this review, we sought to examine and challenge these four dogmas, and propose other interpretations or simply their replacement with alternative views.

 

They give the conventional wisdom as: intelligence is related brain size, brain size is related to cerebral cortical size. But they point out that the cerebellum keeps its ratio with the cortex, the cerebellum has more neurons that the cortex by a factor of 4 and, further, has a lot to do with intelligence. Although the neuron density is much higher in the cerebellum, there are many fewer glial cells.

 

The idea that humans are outliers on graphs of body size against brain size ignores the difference in various types of animals. We are not dramatically off the line for higher primates.

 

Cortical columns are thought to contain 147,000 neurons in each cylinder of about 1mm squared at the surface (except for a few areas) across all mammals. But this has not stood up to evidence. Surface area increases more slowly than neuron numbers and there is not a firm relationship between density and thickness.

 

Here are some figures and their error ranges given in the paper:

Whole Brain

1509(+- 300) grams / 171(+- 14) billion cells / 86(+- 8) are neurons and 85(+-10) glia

Cerebral cortex grey and white matter

1233(+- 234) grams / 77(+-8) billion cells / 16(+- 2) are neurons and 61(+-7) glia

81% of brain mass 19% of brain neurons

Cerebellum

154(+- 19) grams / 85(+- 7) billion cells / 69(+- 7) are neurons and 16 (+- 2) glia

10% of brain mass 80% of brain neurons

Basal ganglia and diencephalon and brainstem

118(+- 45) grams / 8.5(+- 1.5) billion cells / 0.7(+- 0.1) are neurons and 7.7(+-1.5) glia

8% of brain mass 1% of brain neurons

 

Surprised?

 

 

ResearchBlogging.org

Lent, R., Azevedo, F., Andrade-Moraes, C., & Pinto, A. (2012). How many neurons do you have? Some dogmas of quantitative neuroscience under revision European Journal of Neuroscience, 35 (1), 1-9 DOI: 10.1111/j.1460-9568.2011.07923.x

the Freud hangup

It continues to amaze me that there are still scientists who have very kind words to say about Freud’s theories. I tend to think that the leftovers of his ideas have a very negative effect on neuroscience.

Here the sort of thing I mean. Jonah Lehrer who is a great (I mean great) blogger, starts a recent posting (here) with this paragraph:

Sigmund Freud gets a bad rap from modern science. (The immunologist Peter Medawar summarized the feeling of many with his remark that psychoanalysis is the “most stupendous intellectual confidence trick of the twentieth century.”) Sure, Freud’s theories mangled a lot of details — we no longer worry about penis envy or the Oedipus complex — but he was shockingly prescient on the big themes. In recent years, it’s become clear that, as Freud always insisted, the unconscious is the dominant force in our mental life. (What Freud called the id is now a network of brain areas associated with emotion, such as the amygdala and nucleus accumbens.) He was mostly right about the logic of dreams, which often regurgitate those parts of experience we store in long-term memory. And he was basically correct to imagine the mind as a set of conflicted drives, with reason competing against the urges of the passions. We expend a lot of neurotic energy holding ourselves back.

The paper that Lehrer is reviewing does not mention Freud or Freudian theories. It discusses infant attachments to mothers, but in a modern not Freudian way. When I read this paper it did not remind me of Freud.

So Freud insisted that the unconscious is the dominant force. That seems to me to be a small positive compared to the large negative in the kind of dominance he gave it. He painted that dominant force as the dark side in opposition to consciousness. Freud’s picture is all conflict and sabotage; it is unrealistic and to me has always been unconvincing. This Freudian fear of the unconscious is actually holding back the recognition of its importance.

A reasonable picture is of parts of the brain cooperating most of the time to protect an individual’s well-being. Instead of artificial divisions, science is more and more finding that parts are working together or achieving balance rather than fighting.

Possible functions of consciousness 11 - summary

Many people, for a long time, have thought that the function of consciousness was thought, all thought or just all rational thought, or control of action and decision making. Talk of the conscious mind and conscious will than imply to particular sort of consciousness. When thought and control turned out to be largely or wholly unconscious, there appeared to be no function left for consciousness. It might be just an interesting by-product of mental activity but not important to it. We could be zombies and it would make no difference. But no - just because consciousness is not the star does not mean it is not in the play. Just because it is not perception, cognition or action does not mean that it is not involved.

David Chalmers is probably the most prominent dualist philosophy today. He coined the notion of the ‘hard problem of consciousness’. It is explaining the phenomenal, the subjective ‘what is it like?’ of consciousness. He has put forward an argument based on a thought experiment: there could be physical duplicates of human beings that behave just like us but lacking qualitative experience/consciousness – and because we can conceive of these ‘zombies’ they must be logically possible – and because they are logically possible it follows that qualia and feeling are not wholly physical. Thought experiments are always suspect. I personally cannot conceive of someone behaving like a normal conscious human while lacking consciousness. That is ludicrous. Nor does conceiving of something make it logically possible. I can imagine flying without wings or effort but that does not convince me that it is possible. And finally why would logically possible zombies have to be other than physical? Every step of this argument is not convincing to me. Lets try the equally weak counter thought experiment – it is not possible to conceive of a non-physical process – therefore non-physical processes are not logically possible - consciousness is a process and therefore it is a physical process. Thought experiments are only as good as their premises. If you start with a dualist premise, you can come to a dualist conclusion and if you start with a non-dualist premise, you can come to a non-dualist conclusion.

So it seems that the problem for the dualist is the phenomenal experience, the qualia, and their seeming non-compatibility with a purely material brain. Not to be obtuse, I wonder, what would the experience of the world be expected to feel like in a physical brain? How would the nature of surfaces be rendered? How would we know how much light they would reflect? What wavelengths of light they absorb? How smooth they are? Etc? If someone has a better way than the one we experience normally, than they should say so. The evolutionary process has given us a very good way to experience the world, and we should not be surprised that it is impressive. We do not have a clear picture of how it is done but I can think of no reason why it cannot be a purely physical process.

There are wide and narrow definitions of consciousness. At its narrowest, consciousness is simply our experience of a construct of the world and us in it (working memory, attention and so on are not included). All sorts of processes are going to feed into that experience and all sorts of processes are going to use that experience. But the experience itself is essential to a great deal that goes on in the brain; it has functions, important functions. It is not a frill, spandrel, by-product or a recently emergent human only thingy.

The previous 10 posts in this series outline some possible functions that this construct, and our experience of it, provides. (1) The nature of the construction matches the nature of memory so that the contents of consciousness can be stored in declarative memory (episodic and semantic) and the construct can hold retrieved memories. It can also hold imaginings. This connection to declarative memory gives us our autobiographic narrative, our body of formal knowledge, the material and context we use to imagine and to update old memories. The connection to working memory allows System2 cognition, sequential procedures, use of language/math/logic, the learning of most skills. (2) The prediction of the sensory results of ongoing motor acts is displayed in the conscious construct and can be compared to in-coming sense information in order to monitor and correct movement. It also appears to tags actions according to how they were initiated, giving us a source of learning and a sense of responsibility. (3) The construction provides a sense of location for objects in a three dimensional space, of time, of a theory of mind, of a stable self, and probably other ‘frameworks’ that are ‘hardwired’. (4) The construction provides ways for the brain to communicate with itself. It is a place for attention to be registered which informs the whole brain of what is significant or priority. By the global awareness of the contents of consciousness, the brain can coordinate processes that do not ordinarily work directly together. And with internal speech, complex communication within the brain is possible by attention on words.

Consciousness does not ‘do perception’ but is necessary for many uses of perception. It doesn’t ‘do memory’ but is a necessary input/output for large parts of memory. It doesn’t ‘do cognition’ by facilitates an important style of cognition. It doesn’t ‘do movement’ but is part of the motor monitoring. It doesn’t ‘do learning’ but is necessary for all but the most simple learning. It is just a model. It does do awareness, experience, qualia, feeling. It is the model that we live our whole lives inside.

Here are the links to the entire series:

Possible functions of consciousness 1 - leading edge of memory

Possible functions of consciousness 2 – gate to meaning

Possible functions of consciousness 3 – working memory

Possible functions of consciousness 4 – place to imagine

Possible functions of consciousness 5 – create ‘now’

Possible functions of consciousness 6 – presence ‘here’

Possible functions of consciousness 7 – attention on the significant

Possible functions of consciousness 8 – broadcasting waves

Possible functions of consciousness 9 – marking agency

Possible functions of consciousness 10 – being oneself

Possible functions of consciousness 11 - summary

Possible functions of conciousness 10 - being oneself

Now we come to the most confusing part of possibilities of how consciousness may be useful – self. Of course consciousness does not give us our unique existence. The continuity of the organization of our physical bodies from conception to death is what defines our existence as organisms. Our awareness of our existence is just that, awareness, and not what brings about our existence.

 

Consciousness to be useful has to include the whole of ourselves in the model of the world. We have to model ourselves. What would be the use of the slight prediction of the conscious ‘now’ if it did not include predictions of our own movements? What use would be memories that did not include our part of the scene? So we have a model of ourselves (of dubious accuracy) and that model has continuity through our episodic memory as an autobiographical narrative. But does the conscious self have any use beyond completing the working model of the world? Is there any function of consciousness that I am sitting in a chair that is different from the consciousness of the chair I am sitting in? If there is a difference it is likely to be centered on ToM, qualia or communication.

 

The structure that we use to model ourselves is probably useful to model others. Theory of Mind (or ToM as it is usually written) is part of many explanations of how we interact with others. It ascribes to others that same components and relationships that we use to model our own actions. For example, an idea like guilt is a feeling we have when they feel we are responsible for a ‘bad’ thing. In our model of ourselves ‘guilt’, ‘responsibility ‘and ‘bad’ become real things. We can then see evidence of these sorts of element of ToM in the actions of others. This projection of our model of ourselves onto others allows us to predict their behaviour and it allow us to make decision on how dangerous or helpful another person may be. Being a social animal, this is more then useful; it is almost necessary to survive in society. We seem to come into the world with the machinery to construct this model of our own mind. The model is extremely useful but not very accurate. Many problems arose, especially in philosophy and psychology, because this model was taken as accurate outside the everyday use it was evolved to satisfy. If we need to delve deeper into the nature of thought we need to avoid trusting introspection and rely to experiment. Introspection can only show us the ToM model of our thoughts. There is no direct knowledge of ourselves or anything else – Get use to it!

 

The elements and relationships of ToM are, however, interesting and some of them are somewhat valid. If not than how would they be able to make predictions of our and other’s actions. Take what is variously called someone’s personality, character or nature – we see a vague pattern to an individual’s way of living. There is no doubt that we have patterns and that we get to know people in the sense that we understand their patterns of behaviour. Experts keep making new lists of ‘types’, trying to tie down these patterns. Ordinary people accumulate archetypes in their concepts. I personally think that there will never be a completely satisfactory set of types or archetypes, because we are too individual. But we can have a pretty good set.

 

Although we know that there are problems with an unchanging self such as phantom limbs, out of body experiences and a long list of other oddities, we still feel there is a core, stable self. If we see things and hear things then there must be a self that is seeing and hearing. If we remember things then there must be a rememberer remembering their past. So the very vividness of our experiences seems to make a core and permanent self indispensable. The self is not as real as it seems, just like everything else about consciousness, but is useful.

 

This question of the vividness of experience is extremely important to many philosophers. We all work on the assumption that the qualia of our experience is very similar to others but not identical. We do not know for sure but then there is nothing that we know for sure. In this context a paper by Ramachandran and Hirstein (citation below) is interesting. Here is the abstract:

Neurological syndromes in which consciousness seems to malfunction, such as temporal lobe epilepsy, visual scotomas, Charles Bonnet syndrome, and synesthesia offer valuable clues about the normal functions of consciousness and `qualia’. An investigation into these syndromes reveals, we argue, that qualia are different from other brain states in that they possess three functional characteristics, which we state in the form of `three laws of qualia’ based on a loose analogy with Newton’s three laws of classical mechanics. First, they are irrevocable: I cannot simply decide to start seeing the sunset as green, or feel pain as if it were an itch; second, qualia do not always produce the same behaviour: given a set of qualia, we can choose from a potentially infinite set of possible behaviours to execute; and third, qualia endure in short-term memory, as opposed to non-conscious brain states involved in the on-line guidance of behaviour in real time. We suggest that qualia have evolved these and other attributes (e.g. they are `filled in’) because of their role in facilitating non-automatic, decision-based action. We also suggest that the apparent epistemic barrier to knowing what qualia another person is experiencing can be overcome simply by using a `bridge’ of neurons; and we offer a hypothesis about the relation between qualia and one’s sense of self.

And the hypothesis:

One way to approach the question of how our account of qualia relates to the question of the self is to ask from a scientific point of view why something like filling in of the blind spot with qualia-laden representations occurs. … the line of reasoning should run: ‘If qualia are filled in, they are filled in for something.’ … Now, what is the ‘something’ here? There exists in certain branches of psychology the notion of an executive, or a control process. These processes are generally taken to be frontal, or prefrontal, but we would like to suggest that the something which qualia are filled in for is a sort of executive process, but a limbic one, rather than a frontal one. This would be a process involved in connecting motivation and emotion with the choice of actions to perform, based on a certain definite incoming set of qualia — very much the sort of thing which the self was traditionally supposed to do.

 

For humans there is an added usefulness to the conscious self. The self can talk to itself. Words can control the focus of attention so one part of the brain can influence other parts with the spotlight of attention by using language in the stream of consciousness. The internal conversation also is passing through working memory and this is a way to make serial journeys through ideas and concepts. But we have already supposed this to happen (see discussion of working memory and of broadcasting across the brain) – what is added with the verbal conversation of the self with the self? Language brings a new class of objects into consciousness. People can manipulate in consciousness/working memory visual objects, sound objects, movement objects and so on through all the channels of sensory input. But verbal objects, words, open another window of non-sensory objects like justice, education, naval, magnificent.

 

So the self is useful in understanding others, communicating within the brain and it also helps to explain qualia (although I wonder if qualia require an explanation and whether self is a suitable one – many people think otherwise).

 

There is only the final one of this series left to come. Here are links to the previous ones:

Possible functions of consciousness 1 - leading edge of memory

Possible functions of consciousness 2 – gate to meaning

Possible functions of consciousness 3 – working memory

Possible functions of consciousness 4 – place to imagine

Possible functions of consciousness 5 – create ‘now’

Possible functions of consciousness 6 – presence ‘here’

Possible functions of consciousness 7 – attention on the significant

Possible functions of consciousness 8 – broadcasting waves

Possible functions of consciousness 9 – marking agency

 

 

ResearchBlogging.org

V.S. Ramachandran and W. Hirstein (1997). Three Laws of Qualia: What Neurology Tells Us about the Biological functions of Consciousness, Qualia and the Self Journal of Consciousness Studies, 4 (5-6), 429-458

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