Summary April 29 2009


This blog has reached 100 posts and I feel it is time for a little summary. The object is a make it easier for my visitors to find what they want among the posts. I have made a list of general ideas/questions that I am trying to investigate, and then, for each heading, I list the posts that apply to that idea.

Purpose of the blog

The aim of this blog is to prepare people for the revolution that is going to happen soon in neuroscience. The very first post (1 Jun 08 aims ) outlined the scope of the blog. The aims are enlarged on later in (10 Aug 08 scientific shocks). To give an indication of the type of material that was intended in the blog an early post gave a list (12 Jun 08 what do we know about consciousness) and another gave probable functions (2 Jul 08 does sconsciousness have a function). Putting consciousness in context was the purpose of (9 Oct 08 one way to look at consciousness).

 

A different way to look at consciousness

Some posts have been specifically written to help people come to grips with a different way of viewing their mental life. These posts hardly contain any quotes or links to scientific material. I have used some descriptions of my own way of seeing myself: (6 Jun 08 living without a conscious mind) (10 Jul 08 decisions) (15 Aug 08 who is watching) (18 Oct 08 why make problems) (15 Nov 08 metaphors for consciousness) (30 Nov 08 metaphor) (15 Dec 08 a few definitions) (18 Mar 09 Little thought experiment) (22 Feb 09 A framework) (23 Apr 09 History of the quest)

Some posts look at more specific problems in understanding consciousness

Old ideas that get in the way

There are ways of thinking that interfere with understanding the brain. (12 Dec 08 a different angle)

Some ‘how’ hypotheses

There are some hypotheses that seem very convincing. So far we have taken a quick look at the following:

Miscellaneous bits and pieces

(23 Jul smell is different), (30 Aug 08 do grandmother cells fly?), (12 Oct 08 metaphor to embodiment), (27 Nov 08 not inside us), (11 Jan 09 Epistemology changes), (20 Jan 09 Proprioception), (16 Feb 09 Other definitions) (20 Apr 09 A kluge?)

My own tentative view


Here is my (tentative) way of looking at consciousness.

Mind is a biological function (like circulation or digestion) and the brain is the principle organ that accomplishes this function. Brain ‘does’ mind. Mind is not the only function of the nervous system but it is the major function of the forward parts of the brain. Brain ‘is for’ mind. This is in the same sense that a heart does circulation and a heart is for circulation.

The mind function consists of: building, maintaining and refining a model of reality; using the model to predict, plan, decide, initiate and control responses to reality; and storing/maintaining an edited version of the model as a memory of experience for comparison and learning. This model includes a self in the world. This modeled world is not the same as reality. Neither is the modeled self the same as reality. The more effectively reality is modeled, the better the model. Consciousness is the edited model, prior to, during or immediately after it is stored as a memory.

The edited model has a focus and a larger outline. In other words, a large part of the model is in the edited version but with sparse detail, while one aspect is in detailed focus. Introspection happens when the focus of consciousness is the edited version itself. Introspection is not inspection of reality or of the brain’s model of reality or of the process of forming that model but it is inspection of the edited version of the model prepared for memory.

The model is a pseudo real time model. It contains a modeled ‘now’. ‘Now’ in the model is simply the immediate past (from memory) of the model projected by prediction into the immediate future giving a model of ‘now’. The same or similar modeling processes can stimulate the past and the future as well as the pseudo now. This appears in consciousness as a past-now-future continuum with additional flash back, flash forward, and timeless imaginings occasionally superimposed.

Modeling is constrained by the architecture of the brain and by the primitives (like movement) it builds and elaborates on. The modeling process creates discrete objects occupying locations in three dimensions. The modeling process attaches properties to the objects (and other elements) of the model such as colour or pitch. The modeling process models motor activity from goals, intention, initiation, to action and outcomes. It monitors for surprises or inconsistencies in order to correct its control of perception and motor activity.

We can think of the brain, doing its modeling, as the ultimate artist creating the continuous qualia of our lives. We can also think of the brain, doing its modeling, as the ultimate scientist continuously comparing its prediction with what reality gives it in the next fraction of a second and correcting its model of reality accordingly.

Very little of this modeling process is available in the edited version for consciousness/memory. Even in the areas of focus, the process is hidden except for shorthand indicators (fringe perceptions) like: this is the past, a decision is made, that was good, that is known. If an attempt is made to follow the process through introspection, the result is educated guesswork.

How does the brain create this model? It does not create a continuously changing model but a series of ‘snapshots’. These are melded together in working memory to give the impression of a stream of consciousness. Activity in the brain builds up to each installment of the model. This activity amounts to an increase in the synchronization over larger and larger areas of the brain. The synchronization appears to connect all the components and levels of analysis into one whole – a particular pattern of neural activity. And it is the wherewithal to recreate the pattern that is stored and then further processed.

The synchronization is achieved by the interaction between the thalamus and the cortex. Almost all inputs into the cortex pass through the thalamus and almost all cortical areas send signals back to the thalamus. The thalamus appears (in a rough way) to initiate and control cortical activity. The different areas of the cortex are connected to one another as well as to the thalamus. This gives billions of interlocking and overlapping, parallel feedback loops. Massive, overlapping parallel feedback loops in some arrangements can settle quickly on a stable condition. This would give synchronization in a model that was the ‘best fit scenario’ incorporating sensory input, memory, actions in progress etc.

This way of looking at consciousness gives an identity between the whole of the mind (modeling) and the activity of part of the brain (modeling) – they are one and the same without a trace of duality.

Other philosophical problems can be approached. Epistemology would change from search for knowledge to search for understanding. Modeling does not result in knowledge but in understanding. The criteria of a good model is not ‘truth’ but relevance, consistency, extent, and predictive accuracy. A good model is very much like a good scientific theory – it is reliable but not ‘truth’ in a pristine sense. The modeling process is capable of choice but it would not be free from constrains although, under introspection, it would appear to be freer than it was. As the modeling is affected by the attitudes, values and goals of the brain and the attitudes, values and goals are affected by the modeling, the whole system is responsible for its actions and therefore can be morally judged. All our philosophical attitudes would have to shift to accommodate this new way to look at our thought but there need not be a radical change.

 

History of the quest


The time has come to put forward the ideas that I (tentatively) favour. Tentativeness is important for me in the current state of knowledge. We cannot say, with any sort of completeness, what the cells in the brain actually do, especially the glia cells – maybe something to do with calcium movements and voltages that are not action potentials. Our picture of synapses is also somewhat foggy, especially the mechanics of how the number and strength of synapses changes as the brain forms memories and learns. The connections of neurons has only started being mapped. Some of the main highways are known but not the details. And so it goes. A wholly new aspect of the brain could appear out of left field any day and change the understanding of the brain overnight. So I must be tentative. Nevertheless it is constructive to speculate, and fun as long as it is not taken too seriously. In the next post, I will speculate, but first I give some history.

Every once in a while, we can experience a culture shock within our own culture. We find that some idea that we took to be a vague and sloppy metaphor, is a literal truth to many others. In my late teens (in the 1950s) I took a psychology course in high school. The material was not always believable but like a good student I learned it and gave it back in exams. That did not mean I had to accept it. Being a good student, I usually accepted what I was taught. However, I just could not believe 1950′s psychology. I became aware that the other students had no trouble accepting the material. It fit with their world. That was a culture shock. Shortly after this I first heard about dyslexia and realized that it explained my reading and writing difficulties. I made the assumption that the reason I had no feeling of comfort with Freud’s ideas was because I was ‘made differently’. The thing that was most unbelievable was that there was a ‘conscious mind’ and a separate ‘unconscious mind’ or ‘subconscious mind’. It was inconceivable to me that I had two separate minds. I had one and what was more, if I had to choose between a conscious or an unconscious mind then I would have to choose unconscious. This attitude on my part was because I thought of mind as the thing that thinks. As there was no trace of any mechanisms of thought in my consciousness, my thinking must happen elsewhere. I could not feel any metaphorical gears or levers or other mechanisms doing any thinking work in my consciousness, the only conscious awareness was of the finished final products. Pop, there’s another thought, nicely related to the last one. Even some puzzles done in a fixed stepwise fashion had no feeling of ‘how’ each step was accomplished. I had consciousness and I had a mind but not a conscious mind.

I became less sure that I was made so differently from everyone else when I questioned them and found that others did not see anything odd about what I said or did. They also could not describe any conscious thought processes either but just finished thoughts. I might be made different in terms of dyslexia but probably not in terms of conscious experience.

Sometime, about 40 years ago, in the 1970s, I sat on the top step of the stairs and tried to figure out how I knew when I was conscious. I realized that the answer was memory. If I could remember being conscious, I believed I was conscious at that time. If there was a gap in my memory, I believed I had been unconscious during that gap. If I was conscious, I had a memory and if I had a memory, I had been conscious. Introspection did not show me consciousness, memory of introspection did. I formed the tentative belief that consciousness was like the leading edge of memory and not really separate from memory. This is not particularly helpful because memory is almost as mysterious as consciousness, maybe more.

I took ‘Biological Basis of Behavior’ from the Open University and began reading papers and books on the subject of consciousness.

About 30 years ago, in the 1980s, I had an argument with a friend about whether it would be possible to draw a one-to-one mapping between a biological account of the brain, a psychological account of behavior, and a philosophical account of the mind. I thought that if you had the right three accounts, they would fit together and I tried to produce such a mapping. It had a lot of holes but I felt it showed that the enterprise would someday be possible. I have re-read it a couple of times since I wrote it and noted where more reading or thinking was required. The mapping is a sort of on-going project.

What started me creating this blog was the explosion in material on functioning of the brain. I thought of my friends who were not aware that a revolution as big as the Copernican revolution, or the Darwinian one or the quantum mechanical one, was just about to happen in neuroscience. It was going to be hard for people to change the way they thought about their minds. I could try to give them (and me) a head start in little incremental posts. I was already following the science and therefore just needed to write the posts.

The next post will be on my tentative model and then a summary of the first 100 posts.

A kluge?


There is an idea in the air, in the background, hovering about, that the functioning of our brains is far from optimal. No doubt our thinking is not perfect but not in the way that many people imply.

Take vision as an example. The argument goes: vision is about forming an accurate picture of what is in front of our eyes, therefore any deviation from that accuracy is an imperfection that contaminates our sight. So illusions get treated as a weakness of the system. Then we notice that the illusions help us with consistency, depth perception, prediction and so on. Illusions are not weaknesses at all but very useful aspects of vision that are only noticeable in ambiguous and artificial situations.

Or take language as an example. The argument goes: language is about forming logical statements about reality, therefore any deviation from the logic of a language’s grammar is a weakness in our use of language. But we really know that language is not about logic but about communication. And we know that language is only a part of communication. When people speak they are not striving for good logic but for good communication. The problems with logic become visible when language is written down and then examined minutely and out of context.

Or take decision making. The argument goes: good decisions are rational decisions, emotion interferes with rationality and therefore emotion should be eliminated from decision making. However, emotion is how we establish a value system. We cannot make good decisions if the only value system we accept is a monetary (or similar) one.

Here is the way we should look at our weaknesses. We have to take time into consideration. We do not have the time to form an accurate image of the world before the whistle blows and we have to act in that world. We need some ‘quick and dirty’ tricks along side more detailed analysis to get us through life. When we speak we do not always have time to communicate in well formed logically pristine sentences. We do the best with the time available – the best at communication not at logic. Nor do we have the time to make complicated spreadsheet type analysis for our decisions. A decision that is too late can be as bad as a weak decision, sometimes worse.

Here is another way is see the problem. No doubt in elementary school you were taught to roughly estimate the answer to a mathematical problem before doing all the long hand arithmetic. Advice that is mostly ignored. I was also taught to use a slide rule first before having to use other methods for more significant figures. I was told to do calculations on a calculator with well rounded numbers and accurate numbers of zeros first and then do the calculation with the full numbers. Three different teachers at three stages of my life giving me the same message, “take a little time and protect yourself from huge, gross errors but comparing your answer to a rough estimate.” It seems our brains do both quick estimates and slow calculations and they are checks on one another.

Finally many people seems to dislike the wet, wiggling, squashiness of living things. Accuracy is not an end in itself, life is. Logic is not an end in itself, life is. We may see other goals but our biology has its own. We should not consider our brains as faulty unless they are failing in a biological sense.

Attention 2

Here is more from Psyblog (here) on attention. This time on the independence of eye direction and attention.

“Eye direction normally coincides with where attention is directed but it is such an important social signal that disguise is sometimes necessary. Take these for instance:
People in close proximity like rail commuters who can watch each other by adopting a fixed gaze and letting their attention wander around the visual field.
Parents keeping tabs on their children out of the corner of their eye while looking at their conversational partner.
Skilled sports people hiding their intended passes or moves by using their peripheral vision rather than looking directly…
Posner and others argued that it is our attention moving around the visual field, often remarkably independent of our actual gaze direction. Indeed even if we’re looking directly at something, and when we don’t expect to see it, we’re no more likely to notice it than if it appears on the edge of our vision…
It appears that attention can be likened to a spotlight roving across our vision like a virtual eye, just picking out the things in which it is interested; it’s not as attached to where we point our eyes as we might imagine. ”

Attention 1

It is easy to confuse attention and consciousness. Attention seems even part of consciousness. Some articles in the blog Psyblog (here) make an interesting take on attention. In fact, what I found at this blog was so engaging that I intend to visit it regularly.
An article by M. Miller from Nature 2003 is cited by the blogger. It shows that visual attention can be divided between two things. Here is the abstract:

“By voluntarily directing attention to a specific region of a visual scene, we can improve our perception of stimuli at that location. This ability to focus attention upon specific zones of the visual field has been described metaphorically as a moveable spotlight or zoom lens that facilitates the processing of stimuli within its ‘beam. A long-standing controversy has centred on the question of whether the spotlight of spatial attention has a unitary beam or whether it can be divided flexibly to disparate locations. Evidence supporting the unitary spotlight view has come from numerous behavioural and electrophysiological studies. Recent experiments, however, indicate that the spotlight of spatial attention may be divided between non-contiguous zones of the visual field for very brief stimulus exposures (<100 ms). Here we use an electrophysiological measure of attentional allocation (the steady-state visual evoked potential) to show that the spotlight may be divided between spatially separated locations (excluding interposed locations) over more extended time periods. This spotlight division appears to be accomplished at an early stage of visual-cortical processing.”

This does seem to indicate that attention is a complex concept and not just another word for consciousness. If each sense mode has zero, one or more focuses of attention at any time, plus perhaps other things (non-sensory) being attended to, then attention may be a busy little area.

Visual memory

In a recent ScienceDaily item (here) there is a report on a paper, Short-Term Memory for Figure-Ground Organization in the Visual Cortex, by P. O’Herron and R. von der Heydt. The problem they looked at was the stability of vision.

“As we look at the world around us, images flicker into our brains like so many disparate pixels on a computer screen that change every time our eyes move, which is several times a second. Yet we don’t perceive the world as a constantly flashing computer display.”
“…Recent studies have hotly debated whether the visual system uses a buffer to store image information and if so, the duration of that storage,…We found that the answer is ‘yes,’ the brain in fact stores the last image seen for up to two seconds.”
“The image that the brain grabs and holds onto momentarily is not detailed; it’s more like a rough sketch of the layout of objects in the scene. This may elucidate, at least in part, how the brain creates for us a stable visual world when the information coming in through our eyes changes at a rapid-fire pace: up to four times in a single second.”
“The study was based on recordings of activity in nerve cells in the V2 region of the brains of macaques, whose visual systems closely resemble that of humans…. discovering memory in this region was quite a surprise because the usual understanding is that neurons in the visual cortex simply respond to visual stimulation, but do not have a memory of their own.”

This fits with the idea that there are two levels of conscious images: a very detailed image of two or three aspects of the scene which changes often and a much, much less detailed image of the whole visual field that changes far less often.  In combining these two levels, we have the feeling (illusion) of seeing the whole visual field in detail all at once. What happens for vision is probably also happening in the other senses.

Conscious computer

I have not been able to read the original but the abstract sounds very interesting. The paper is called Self-Consciousness for Artificial Entities using Modular Neural Networks and here is the abstract.

“One of the most puzzling cognitive features is self-consciousness. A considerable amount of research has been conducted on this question in different fields like Psychology, Neurobiology and Cognitive Science. Self-consciousness implies not only self or group recognition, but also real knowledge of one’s own identity. In this paper, a cognitive architecture of self-consciousness for autonomous artificial entities (holons) is proposed. This cognitive architecture includes: abstraction, self-representation, other individuals’ representation, and action modules. It also includes a learning process of self-representation by direct (self-experience based) and observational learning (based on the observation of other individuals). For model implementation a new approach is taken using Modular Artificial Neural Networks (MANN) due to their biological inspiration, modularity and adaptability. We explain the cognitive architecture that enables dynamic self-representation. For model testing a multi-holon virtual environment was implemented. We analyse the effect of holon interaction, focusing on the evolution of the holon’s abstract self-representation. Finally, the results are explained and analysed and conclusions drawn.”

So using computer programs that mimic groups of neurons this Spanish group lead by Milton Martinez Luaces have produced self-aware programs. ScienceDaily has an item on this research. (here)

“….This research represents a dual advance in the modelling of awareness-associated cognitive functions. On the theoretical side, it applies the theory of informons and holons to awareness structures. An informon is an information entity. It can take the form of data, news or knowledge. The term holon refers to autonomous entities that act both as a part and as a whole.

On the practical side, awareness-associated processes were simulated and influenced the design and development of software models. To do this, modular neural networks were used to develop multi-entity simulators. The networks were used to simulate several scenarios of interaction between their own potential and that of the systems with which they interact.

In the case of human beings, self-awareness does not imply just an abstract image of what one is, but also an image of one’s trajectory throughout time. This research also modelled the time dimension of self-awareness using time-delay neural networks. These networks have shown, in different interaction scenarios, that the image that each entity has of its qualities in the past or its expectations for the future has an impact on how it interacts with other entities. For example, a figure reveals how interaction with other artificial entities, in this case in a competitive scenario, enables these entities to develop self-awareness.

In the same way as individuals tend to form groups with common interests and, as a result, develop a sense of belonging at more than one level, artificial entities may interact similarly to achieve a particular purpose….”

I hope more detail is available in future.

 

Biology and culture

On the Edge site there is a video featuring Denis Dutton.( here) He is the author of The Art Instinct. What he has to say is a little off the subject of this blog, consciousness, but it does highlight the turf war between biology and culture in explaining human thought.

Darwinian aesthetics is not some kind of ironclad doctrine that is supposed to replace a heavy postructuralism with something just as oppressive. What surprises me about the resistance to the application of Darwin to psychology, is the vociferous way in which people want to dismiss it, not even to consider it. Is this a holdover from Marxism or religious doctrines? I don’t know. Stephen Jay Gould was one of those people who had the idea that evolution was allowed to explain everything about me, my fingernails, my pancreas, the way my body is designed—except that it could have nothing to say about anything above the neck. About human psychology, nothing could be explained in evolutionary terms: we just somehow developed a big brain with its spandrels and all, and that’s it.

Nicely put, I thought.

No conflict with science


The Scientific American reported on the Dalai Lama’s address to the Society for Neuroscience in November. (here) Apparently attendance at the speech was exceptional. The Dalai Lama believes his religion does not conflict with science.

“Today when this political and religious leader is faced with conflicting explanations of life’s mysteries, the Dalai Lama still favors scientific evidence over classical Buddhist concepts. At a time when Americans are battling state by state for religion-free science education, he urges people to take a path of peace between the perspectives. An estimated 14,000 people attended his lecture on November 12, 2005, at a meeting of the Society for Neuroscience in Washington, D.C., with most of them watching from overflow rooms where the talk was broadcast on large screens. Dressed in gold and crimson robes, he suggested a healthy dose of skepticism toward religious pronouncements. Although science can overturn spiritual teachings, people can benefit from scientific understanding without losing faith, he reasoned.
But the Dalai Lama also emphasized that religion can help science, not just hinder it. In particular, he urged neuroscientists not to discount the role of Buddhist traditions on the brain, specifically meditation. “Try to find reality with an open mind,” he said, referring both to investigations in science as well as to studies in Buddhist thought. “Without investigation we can’t see reality.”
The neuroscientists in the auditorium responded with approval, especially those who have examined the effects of meditation.”