consciousness

Between the Stimulus and the Response: the four functions of the Mind

“Between stimulus and response there is a space. In that space is our power to choose our response. In our response lies our growth and our freedom.” Victor E Frankl

Schematic of an idealized analytical instrument.

Schematic of an idealized analytical instrument. (Photo credit: Wikipedia)

In today’s post I will be drawing heavily from the spiritual traditions of India (Yoga etc), and interested readers are redirected to these excellent sources for more information about the same.

As per the spiritual tradition of India, Mind (or Antahkaran) is made up of four functions or parts. These are Manas, Chitta, Ahamkar and Buddhi. These are typically translated as sensory-motor mind, memory bank, ego and intellect respectively. As an interesting aside, Buddha derives from the common root of Buddhi (budh- to know) and stands for the enlightened one.

Here is a brief description of the four functions:

Manas is ordinary, indeterminate thinking — just being aware that something is there and automatically registers the facts which the senses perceive.

 

The subconscious action, memory, etc., is caused by chitta. The function of chitta is chinta (contemplation), the faculty whereby the Mind in its widest sense raises for itself the subject of its thought and dwells thereon.

 

Buddhi determines, decides and logically comes to a conclusion that something is such-and-such a thing. That is another aspect of the operation of the psyche — buddhi or intellect. buddhi, on attending to such registration, discriminates, determines, and cognizes the object registered, which is set over and against the subjective self by aha?k?ra.

 

Ahamkara — ego, affirmation, assertion, ‘I know’. “I know that there is some object in front of me, and I also know that I know. I know that I am existing as this so-and-so.” This kind of affirmation attributed to one’s own individuality is the work of ahamkara, known as egoism.

There is also a hierarchical relation between these with Buddhi at the top and Manas at the bottom. Now, lets look at each of these more closely.

Manas, or sensory-motor mind, is not just registering stimulus but also responsible for executing actions and may be equated with the sensory/ motor cortical functions of the brain.  It controls the 10 Indriyas (5 senses and 5 action-oriented faculties). Its important to note that Manas is doing both the functions associated with stimulus as well as the response,  though its the first one when it comes to stimulus processing (registering the stimulus)  and the last one when it comes to executing responses/actions ( it blindly executes the action that has been decided / chosen upstream). Of course one could just have a reflex action where a stimulus leads to response, but in majority of human action, there is a space between the two. That space is provided by the rest of the mind functions.

Chitta, or memory-prospecting mind, may be typically equated with the association cortex part pf the brain. Many refer to chitta as the memory or impressions bank, but forget to mention the future oriented part of it. Here is a quote:

The part of the Mind thinking and visualizing the objects, events and experiences from the past or the future (emphasis mine) is called the Chitta and this act is called Chintan.

Its thus evident that Chitta drives Manas not only based on past memories, but also based on future expectations or predictions. From brain studies , we know that the same part of the brain is used for memory as well as prospection.  Chitta using past memories to drive manas (and thus behavior or motivated cognition) I view as being conditioned by classical conditioning processes. Chitaa using future expectations/ predictions to drive behavior and motivated cognition, I view as being conditioned by operant conditioning processes. In many philosophical and spiritual traditions, one of the aims is to get over (social) conditioning. Chitta hinders spiritual awakening by using habits, which is an integral pat of chitta function. The habits are nothing but the conditioning, but again one in stimulus path and the other in response/action path.

Ahamkara, or experiential-agentic self, may be typically equated with consciousness/ conscious and ego-driven self. It knows and say ‘I am’  Conscious entities typically have two functions- experience and agency. It is something it is to be like that conscious entity (experience) and the entity has volition or ability to do things (agency). The concept of self as a conscious entity that has experience (in the stimulus path) and agency (in the response/ action path) is important for this notion of ahamkara. With self comes concepts like real self and ideal self which drive and are driven by experience and agency respectively. The less the discrepancy between the two the better your spiritual growth. An interesting concept here is that of coloring or external decorations- your coloring or how you see your self do lead to downward impact on chitta and manas by contaminating the stimulus/ action.

Buddhi, or knowing-deciding mind, is the final frontier on your path to spirituality.  The typical functions associated with Buddhi are knowing, discriminating, judging and deciding. I think knowing/ discriminating (between stimuli/ actions etc) is a stimulus path function, while judging/ deciding (between actions/ responses/ attending to a stimuli) is a response path function. However I also believe they converge to a great extent here or else we will have a problem of turtles all the way down. Once you start to see things as they are, you are also able to choose wisely. At least that is what the scriptures say and what Boddhisattvas aspire or achieve.

To me this increasingly fine-grained control of what we perceive and how we act , from the gross actions and perceptions of manas to the discriminating decisions of buddhi are very intuitively appealing and also appear to be grounded in psychological and neural processes.

Mindfulness (Buddhism based) has become all the rage nowadays, yet if we look at the spiritual traditions of India, perhaps while Yoga defined as Chitta vritti nirodaha (or “Yoga is the silencing of the modifications of the mind”) does refer to being in the present (here-and-now) and not to be disturbed by the perturbations of chitta (memories of past or expectations of future), one also needs to go beyond just Chitta vritti, to addressing the Ahamkara coloring and finally to try achieving the Buddha nature where there is little disparity in doing and being. (Mindfulness) Meditation needs to move beyond being curious, non-judgemental  and in the present to where one doe shave a judgement function, but one that is perfectly attuned.

How Cotard’s and other phenomena throw light on the self

indexCan the Cotard’s syndrome tell us something about the self? A person suffering from Cotard’s syndrome is likely to claim that he/ she is dead- can such a delusional experience make us appreciate what self is what it isn’t – and more importantly how the sense of self can go awry in some phenomena?

Anil Ananthaswamy, in his exquisitely written book ‘ The Man Who Wasn’t There‘ beautifully illustrates how Cotard’s and other such weird and not so weird phenomena can shed light on the true nature of self (provided the self exists and there is something it is like to have a self- more about this later).

The book is beautifully written, weaving narratives of actual patients suffering from various disorders, with cutting edge research in the field and at all times tying it back to the nature of the self.

Although the eight chapters talk about eight different phenomena- ranging from Cotard’s to deperosnalisation to Autism to schizophrenia to out-of-body experiences and ecstatic epilepsy to BIID ( or having a desire to amputate ones limbs) and Alzheimer’s – there doesn’t seem any discontinuity- nor does it seem as if disparate phenomena are being talked about. With self being the focus, each of these is used to approach the self from a different angle.

I am reminded of the parable of  blind men and the elephant – whereby each blind men could only grasp one part of the elephant. Self is such an elephant in the room. The various chapters do advance our understanding of the self and fortunately, this time, the sum is greater than the sum of the parts, and we are indeed able to get a  sense of the elephant/self!

It would be naive to assume that Anil would have solved the problem of self where great philosophers or scientists of past and present have failed to do so- but he does gives tantalizing glimpses of what the answer might me and at least brings us up to speed with what is being thought of in the philosophical / scientific circles.

The power of the book comes from its very approachable and readable writings style and the humane treatment of its subjects.  Whether its the isolation felt by a BID sufferer who has no means of getting his limb amputated legally or the strangeness felt by those suffering from deperosnailsation, Anil makes the stories vivid- loud and clear in one’s mind;s eyes.

The book is also chock full of interesting facts- some of which I was already familiar with, but got an opportunity to brush up on the latest happenings in the filed, others were new to me – for example I hadn’t realized that people with Cotard’s are typically depressed or that people remember more about their life from between 10 and 30 years (the reminiscence bump) and many such nuggets.

The book is immensely readable and holds your attention from chapter to chapter.  I was almost felling bad about having finished it as I wanted more of the treats to continue.  In a week in which we lost Oliver Sacks, it takes some solace to discover that there are others who are keeping the tradition alive.

Both the erudition , humanity and narration of Anil is superb. While reading the book, I thought he was himself a prominent neuroscientist- its only post reading it I realized he is a science journalist and has also written  a best seller in physics. Surprising how brilliant people are able to make their mark in whatever field they chose to focus on. Quiet coincidentally I had also reviewed ‘Subliminal’ by Leonord Mlodinow- who is also a physicist but has written a good book rooted in psychology.

My advice to readers of this blog- if you loved Sacks, if you loved VS Ramachandran,  or even if you didn’t or haven’t heard about them, do give this book a read- you are going to love the easy style- yet a lot of substance. I, for one , am eagerly looking forward to Anil’s next read.

Neural correlates of conscious access: implications for autism/psychosis

ResearchBlogging.org

First published Electroencephalogram of a human
Image via Wikipedia

There is a recent article in New Scientist about consciousness and its neural correlates and the article focuses on work of Stanislas Deheane and his colleagues and how they are trying to get evidence and proof for the Global workspace theory of consciousness as proposed by Beranrd Baars.

That led me to this excellent article by Raphaël Gaillard that uses iEEG (intracranial EEG) using electrodes placed in brain, but not doing single-cell recording but still working on aggregates but at a much higher spatial and temporal resolution than normal extra-cranial EEG. They used electrodes placed in epileptic patients undergoing surgery and determined the difference in neural activity during conscious and unconscious access.

For differentiating between the unconscious and conscious access they used the popular visual masking paradigm, whereby a target word is presented and then immediately afterwords (after a few ms only) a mask is presented; if the duration of stimuli presentation is less and it is immediately followed by a mask, then though the stimulus is processed unconsciously, it is not available for verbal report and is not processed consciously. In contrast, in the unmasked condition, the target is not followed by a mask and hence is available for conscious access. In the present experiment, the authors used a forward as well as a backward mask and also had a condition whereby a blank screen was present instead of target ; so that effects of processing target alone could be determined after subtracting the effect of masks. the paper is one access and very lucidly written so go have a look!

A quick detour: Bernard Baars global workspace theory posits that consciousness arises when neural representations of external stimuli, are made available wide spread to global areas of the brain and not restricted to the originating local areas. This has also been characterized as an attentional spotlight and whatever comes under the spotlight in global workspace, is widely visible to the rest of the audience (the other parts of the brain) and also gives rise to consciousness. In the absence of coming to focal awareness(spotlight), the processing/representation happens unconsciously by the many different parallel brain modules. Thus, while unconscious representations may arise in brain locally, to become conscious they need to become widespread and available to the entire (or most of) the brain. To boot:

We adopted a theory-driven approach, trying to test experimentally a set of explicit predictions derived from the global workspace model of conscious access. This model, in part inspired from Bernard Baars’ theory [30], proposes that at any given time, many modular cerebral networks are active in parallel and process information in an unconscious manner [22,23,31,32]. Incoming visual information becomes conscious, however, if and only if the three following conditions are met [23]: Condition 1: information must be explicitly represented by the neuronal firing of perceptual networks located in visual cortical areas coding for the specific features of the conscious percept. Condition 2: this neuronal representation must reach a minimal threshold of duration and intensity necessary for access to a second stage of processing, associated with a distributed cortical network involved in particular parietal and prefrontal cortices. Condition 3: through joint bottom-up propagation and top-down attentional amplification, the ensuing brain-scale neural assembly must “ignite” into a self-sustained reverberant state of coherent activity that involves many neurons distributed throughout the brain.

Based on this theoretical framework, the following hypothesis were developed:

Neurophysiological Predictions Derived from the Global Workspace Model

In the light of our model, the masked–unmasked contrast corresponds to a comparison between a visual representation satisfying only condition 1 and a representation satisfying all three conditions for conscious access listed above. The global workspace model therefore leads to the following four predictions.

Prediction 1: a common early stage of processing.
Both masked and unmasked words should evoke similar neural activity within an early time window, reflecting a fast feedforward sweep propagating from posterior to anterior cortices. In particular, invisible masked words should induce transient event-related responses along the ventral visual pathway, as assessed by iERPs and ERSP.

Prediction 2: a temporal divergence.
Following this initial common stage, only unmasked words should be associated with sustained effects. We thus predict a divergence in cortical activation for unmasked and masked words. Given that we contrasted heavily masked stimuli with unmasked stimuli, we expect a progressive buildup of the divergence between these two conditions. In the light of recent high-resolution scalp electroencephalogram (EEG) studies in visual masking and attentional blink paradigms, this temporal divergence is expected to occur within a 200–500-ms window [1,2].

Prediction 3: an anatomical divergence.
The activation of frontal and parietal areas, which are allegedly dense in global workspace neurons, should be particularly sensitive to consciously perceived words (see [32] and Figure 1 of [22] for explicit simulations of this property). Although masked words may cause a small, transient and local activation within these regions, we predict that unmasked words should elicit a global and long-lasting activation of these regions, corresponding to a broadcasting process.

Prediction 4: phase synchrony and causality.
During this late time window, the long-lasting and long-distance neuronal assembly specific to conscious processing should be associated with an intense increase in bidirectional interelectrode communication. Measures of phase synchrony and Granger causality should be particularly apt at capturing this phenomenon.

And this is exactly what they found. They found that upto 200 ms activity in the unmasked and masked condition did not differ significantly and represented an early stage of processing. In the 200-500 ms window (post stimulus onset), there was temporal divergence with there being long-distance beta synchrony, sustained amplitudes and power in gamma band and Granger causality in the unmasked case, but not in the masked case. Further, there was anatomical divergence, with the unmasked condition showing more occipitotemporal activation, while the unmasked condition showing global (and especially frontal) activation. Lastly while local beta synchrony and reverse feed back causality (accounted perhaps by top-down attentional factors that try to focus more given the masking) was associated with the masked condition, long distance beta synchrony and causal imbalance in the feed-forward direction was only found in the unmasked condition, thereby validating the claim that in the unmasked condition the posterior local representations weer made globally available to anterior regions as well (these are my very brief summaries, you should read the original freely available article for nuances and details).

This is how the authors conclude:

The main motivation of our study was to probe the convergence of multiple neurophysiological measures of brain activity in order to define candidate neural signatures of conscious access. Conscious word processing was associated with the following four markers: (1) sustained iERPs within a late time window (>300 ms after stimulus presentation); (2) sustained and late spectral power changes, combining a high-gamma increase, beta suppression, and alpha blockage; (3) sustained and late increases in long-range phase coherence in the beta range; and (4) sustained and late increases in long-range causal relations.

Our results suggest that in the search for neural correlates of consciousness, time-domain, frequency-domain, and causality-based electrophysiological measures should not be seen as competing possibilities. Rather, all of these measures may provide distinct glimpses into the same distributed state of long-distance reverberation. Indeed, it seems to be the convergence of these measures in a late time window, rather than the mere presence of any single one of them, that best characterizes conscious trials.

That brings me back to the new scientist article:

Dehaene’s group had already shown that distant areas of the brain are connected to each other and, importantly, that these connections are especially dense in the prefrontal, cingulate and parietal regions of the cortex, which are involved in processes like planning and reasoning.

Considering Baars’s theory, the team suggested that these long-distance connections may be the architecture that links the many separate regions together during conscious experience. “So, you may have multiple local processes, but a single global conscious state,” says Dehaene. If so, the areas with especially dense connections would be prime candidates for key regions in the global workspace.

Now it is well known that in autism there are more local connections and more local processing; while psychosis/ schizophrenia spectrum is marked by more long-distance connections/ activity. If so , it is not unreasonable to conclude that psychotics may have higher p-conscious experiences while autistics may be stuck at more lower A-conscious experiences. I proposed something like that in my post titled ‘what it is like to be a zombie‘ and you are strongly encouraged to go read it now.

Further we also know that default mode network is highly activated in psychosis and very less in activity in autistics and that is again converging proof. From the new scientist article:

Certain regions of the brain’s global workspace, dubbed the default mode network (DMN), are active even when we are resting and not concentrating on any particular task. If the global workspace really is essential for conscious perception, Laureys’s team predicted that the activity of the DMN should be greatest in healthy volunteers and in people with locked-in-syndrome, who are conscious but can only move their eyes, and much less active in minimally conscious patients. Those in a vegetative state or in a coma should have even less activity in the DMN.

The researchers found just that when they scanned the brains of 14 people with brain damage and 14 healthy volunteers using fMRI. In a paper published in December 2009, they showed that the activity of the DMN dropped exponentially starting with healthy volunteers right down to those in a vegetative state (Brain, vol 133, p 161). “The difference between minimally conscious and vegetative state is not easy to make on the bedside and four times out of 10 we may get it wrong,” he says. “So this could be of diagnostic value.”

While the DMN may be important marker for brain damaged patients, it also has the potential to become a marker for different feels of consciousness sin brain intact but differently wired brains like those of autistics and psychotics.

I believe one way of conceptualizing autism is as a diminishing of consciousness/ subjective experience; while that of psychosis as overabundance of consciousness/ subjective feeling. Maybe that is why shamans of all ages have been closely identified with the psychotic spectrum.

If autistics have more local processing, then perhaps they should be better at tasks involving unconscious stimuli: perhaps that’s why despite their savantic abilities , much of what happens in the autistic mind is not only non-verbal , but also non-conscious and hence not juts not available for verbal report, but not accessible to consciousness.

I strongly feel that adding the consciousness dimension to autism/schizophrenia spectrum may be a good thing and lead to more clarity and new directions in research.

Gaillard, R., Dehaene, S., Adam, C., Clémenceau, S., Hasboun, D., Baulac, M., Cohen, L., & Naccache, L. (2009). Converging Intracranial Markers of Conscious Access PLoS Biology, 7 (3) DOI: 10.1371/journal.pbio.1000061

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What it is like to be a zombie?

I am sure many of you are already familiar with Nagel’s perennial question ‘what it is like to be a bat?  (see this one with some added commentary too). Today I propose to ask a slightly different question ‘what it is like to be a zombie‘? That may seem absurd at the outset, as in many people’s mind Zombies are synonymous with no consciousness. I beg to differ. As I have already indicated in my last post on major conscious and unconscious processes in the brain, there is an easy problem of A-consciousness and there is a hard problem of P-consciousness. I have already tried to breakup A-consciousness in its parts and  I similarly think that P-consciousness is much more that qualia (qualia I envisage as more grounded in sensory or perceptive systems). So given the fact that most zombies are behaviorurally indistinguishable from normal humans, and given the fact that most people who argue for zombie models of humans (that ‘there is no one home to watch/direct the picture’) do still endow the zombie and themselves with the A-consciousness aspects – they do not deny that a representation is made and is consciously available for processing (the theater of consciousness) , it is reasonable to speculate that although lacking full P-consciousness, it would still be something like to feel like a zombie. Let me draw an analogy, in some dissociative disorders, one starts seeing the world as unreal (derealization)  and the self as unreal (depersonalization) ; yet even though one believes oneself to be unreal there is still something it is like to exist in that ‘unreal’ state.

Similarly, though one may model oneself and others as zombies, still it would be something like it is to be in a state that thinks and believes that one is a zombie and also acts accordingly. I am making a leap here. I am assuming that awareness or modeling of ones A-conscious experiences leads to or affects one’s phenomenal consciousness. Thus, in my view , someone who models oneself and others as a zombie, would have a different sort of P-consciousness or what it feels-to-be-like, than a person who models oneself and others as sentient agents  and his P-cosnsciousness would be of a different nature.

Now consider the problem we face when confronted with a world which is deterministic and chaotic at the same time, and which is inhabited by agents which seem to be unpredicatable and constrained at the same time. I have already indicated elsewhere, that people may form tow types of model- one is a statistical/ deterministic model that they may apply to the world; another is a probabilisitic/agentic model that they may apply to the self (as well as other sentient beings).  If one keeps these domains of folk-physics and folk-psychology separate, all is hunky dory; all hell breaks lose (pun intended; zombies are correlated with dead apocalypse scenarios in popular culture) when one applies a deterministic  model (that fits the world) to the self/others. Similarly all hell breaks loose, when one applies an agentic/indetrminsitc model (that fits the sefl/others) to the world.

For today, we will focus on the problem of modeling self, and leave the problem of modeling world for a later day. A self may act differently in many similar/same situations. If it acts the same on each occasion, given the same situation; we can easily say that the situation causes the action. This poses no problem for the zombie (I will refer to a zombie as a person whose self/other conceptualization is as that of oneself/others as machines), as one has a deterministic rule that defines the self- (given situation A-> action B), and thus one can keep one’s model of self as-a-deterministic-being consistent. On the other hand, if the situation A sometimes leads to action B, but at other times to action C, then one has to explain the variance in the behavioral output. Consider first the problem of explaining the variance between-subjects. Given the same situation A, subject Z acts in way B while the subject Y acts in way C.   There is considerable variance. If one assumes all selves as created equal, then all should have behaved similarly. Either one has to grant an extraordinariness and uniqueness to all selves, or if one has a statistical  and ordinary nature of human beings, one has to grant that the subject given the same situation, should have behaved identically. But we all see that there is considerable variance.  This variance is individualistc and one may try to explain this between-subjects variance using subject’s personal history (prior conditioning: a behavioristic model; or repressed emotional experiences/memories: psychoanalytical theory), one may also look at subject’s common ancestral history and use that to explain behavior (genetic differences: evolutionary biology; cultural differences : anthropology ) or one may even look at his holistic experiences and use that individualistic experiential history as a basis for explaining behavior ( consider two identical twins that because of their different sampling of environment may end up as differently conditioned etc). Phew that covers all the major psychological theories that I could remember.

Now lets focus on the problem of explaining within-subjects variance ; given the fact that the Situation is the same (situation A)  and the subject is the same (subject Z), why does the same subject react differently to the same situation (acts in ways B and C). This is a relatively hard problem. One could deny the problem itself and claim that no situation is identical, but hey we are doing armchair philosophy right now, and we have already agreed to the premise of existence of a same situation A when we discussed between-subjects variance above, so it doesn’t hurt to concede that the situation A can be same for subject Z, but he may still react differently in ways B and C. None of the above psychological approaches, if applied in a strict, causal deterministic sense can explain the same subject Z reacting differently to situation A , as the subject Z’s personal history (conditioning, repressed memories) or ancestral history (genes, cultural influences) or even previous experiences and choices remain the same and thus should ideally have led to the same behavior. I am making an assumption here that situation A is repeated twice or more in succession (closely in time) so that one cannot counter and say that conditioning (to take an example) has changed in meanwhile due to situation A itself and thus, as the subject Z (at time t=1) has changed to an extent (by delta effect of situation A on the ‘earlier’ subject Z at time t=0) , so he may react differently at tome t=1 from how he reacted at time t=0.   What we are really doing is doing away with a term of the equation; we are saying subject Z is not constant (it  keep changing- self as constantly changing- a Buddhist philosophical premise and also favored by many in psychology) , but in the spirit of Camus’s Absurdity argument in Myth of Sisyphus, I am not satisfied with doing away one of the variables of the equation itself, so let us see, where this model of self-as-a-deterministic-being leads us to. Now that subject Z remains the same for two iterations of situation A, how can one explain the variance that results in action B at one time and action C at the other. One can again try to dissolve the equation by claiming that there is no unified self in space (earlier argument was that there is no unified self in time- it is a constantly changing in time self) – that is we are not a single self , but made up of many different selves- some conscious, some unconscious etc. Different selves may compete with each other and whoever wins at the moment, directs the show. Again assuming different selves cohabiting the same person doesn’t really feel what-it-is like to-be-oneself , and apart from some multiple-personality disorder (DID) this has not been frequently reported; but more importantly . Granting multiple selves to subject Z  again vanishes one of the terms of the equation, and I am not interested, I want to stay and see where my inquiry takes me to.

If the situation is same, the subject is same and a single one, than what explains the within-subject variance? One has to grant unpredictability to a self that was assumed to be deterministic to begin with. One can now take two routes, either resort to the magical mumbo-jumbo of quantum world and indeterminacy and uncertainty; or  stay in the deterministic world but look at complex systems/ chaos theory etc to explain the apparent indeterminacy.  I believe a zombie will prefer the second route and model the self as a complex-system/chaotic self. One could say that the self/ others are still completely determined, but due to an initial ‘butterfly flapping wings effect‘ the self seems or appears to be unpredictable and will continue to remain unpredicatble because of that ‘original sin’. The original sin may be how the infant took the first breath, whether he cried or laughed when born; what the time of conception was etc etc. Whatever may be the initial condition that escaped measuring, it leads to an unperdicatble self, a chaotic self that one cannot measure in the present and thus cannot predict in the long term- a self that is as fickle and as perdicatble as the waether.

There are important implications to seeing / modeling the self as a chaotic system. That leads to a diminished sense of agency / responsibility as perhaps there is not much one can do to correct the original sin and thus modify/ change ones long term behavior. This diminished p-consciousness of agency and the consequent differential experiences of sensations/ perceptions should also lead to diminished qualia or what-it-feels-to be-like feeling.  Maybe the zombies do feel really like zombies- mechanical and chaotic- going along the life stream in a mechanical , predetermined manner- seeing all and understanding all, even acting and reacting, but feeling impotent and lifeless, perhaps just fulfilling a role which has been scripted by someone else (the initial butterfly flapping its wings or the original sin).

This is a good point to stop, but I would like to thank Melbren, a reader of this blog, who commented on my last post and asked me if I would re-define , give a new name to Autism spectrum disorders. Thta made me think and somehow led to this post. But first his comment:

Very cool post. And I love your blog. I am trying to think about this particular post in terms of your psychotic spectrum–most specifically as it relates to autism. But I am impeded by an overwhelming feeling that if we have a new spectrum–we’ll need new terms. The term “autism” has outgrown its usefulness, don’t you think?

For one thing–if we are to use the framework of a psychosis spectrum–I think there will be a lot of people currently diagnosed with autism who are, in fact, organically more biased toward the opposite end of the spectrum. However, such individuals may still have “stereotypies” that we have come to associate with the term “autism.”

That being said–if you were appointed “word czar of the day,” and, as such, had the authority to scrap all of our conventional terminology and come up with “new and improved” terms that are more in alignment with a psychosis spectrum–what new terms would you choose?

I conceptualize autism as defect whereby people falsely apply a deterministic model (relevant for the world/ non-living things) to the self/others (living things) ; I consider of psychosis as the reverse, whereby one applies an agentic model to the world, thus exhibiting magical thinking etc. Because psychotic spectrum is consptualised in terms of a disability (loss of contact with reality), I would rechristen autism spectrum as the zombie spectrum (loss of contact with agency); of course, If I indeed am the ‘word czar of the day’ I’ll probably rename both as consciousness-orientation (psychotic spectrum)  and reality-orientation (autistic spectrum) and highlight the good aspects of both- shaministic Altered states of consciousness and creativity of schizotypals and the scientific and savantic abilities of the Aspergers. Of course, in a lighter vein, perhaps the autistic spectrum people are ‘muggles’  (believers in ordinariness ) who still have to come to terms with the ‘magic’ (believers in extraordinariness)  of consciousness.

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Major conscious and unconscious processes in the brain: part 5: Physical substrates of A-cosnciousness

This is the fifth post in my ongoing series on major conscious and unconscious processes in the brain. For earlier parts, click here.

Today , I would like to point to  a few physical models and theories of consciousness that have been proposed that show that consciousness still resides in the brain, although the neural/ supportive processes may be more esoteric. 

I should forewarn before hand that all the theories involve advanced understanding of brains/ physics/ biochemistry etc and that I do not feel qualified enough to understand/ explain all the different theories in their entirety (or even have a surface understanding of them) ; yet , I believe that there are important underlying patterns and that applying the eight stage model to these approaches will only help us further understand and predict and search in the right directions. The style of this post is similar to the part 3 post on robot minds that delineated the different physical approaches that are used to implement intelligence/ brains in machines.

With that as a background, let us look at the major theoretical approaches to locate consciousness and define its underlying substrates. I could find six different physical hypothesis about consciousness on the Wikipedia page:

  1. * Orch-OR theory
  2. * Electromagnetic theories of consciousness
  3. * Holonomic brain theory
  4. * Quantum mind
  5. * Space-time theories of consciousness
  6. * Simulated Reality

Now let me briefly introduce each of the theories and where they seem to have been most successful; again I believe that though this time visually-normal people are perceiving the elephant, yet they are hooked on to its different aspects and need to bind their perspectives together to arrive at the real nature of the elephant.

1. Orch-OR theory:

The Orch OR theory combines Penrose’s hypothesis with respect to the Gödel theorem with Hameroff’s hypothesis with respect to microtubules. Together, Penrose and Hameroff have proposed that when condensates in the brain undergo an objective reduction of their wave function, that collapse connects to non-computational decision taking/experience embedded in the geometry of fundamental spacetime.
The theory further proposes that the microtubules both influence and are influenced by the conventional activity at the synapses between neurons. The Orch in Orch OR stands for orchestrated to give the full name of the theory Orchestrated Objective Reduction. Orchestration refers to the hypothetical process by which connective proteins, known as microtubule associated proteins (MAPs) influence or orchestrate the quantum processing of the microtubules.
Hameroff has proposed that condensates in microtubules in one neuron can link with other neurons via gap junctions[6]. In addition to the synaptic connections between brain cells, gap junctions are a different category of connections, where the gap between the cells is sufficiently small for quantum objects to cross it by means of a process known as quantum tunnelling. Hameroff proposes that this tunnelling allows a quantum object, such as the Bose-Einstein condensates mentioned above, to cross into other neurons, and thus extend across a large area of the brain as a single quantum object.
He further postulates that the action of this large-scale quantum feature is the source of the gamma (40 Hz) synchronisation observed in the brain, and sometimes viewed as a correlate of consciousness [7]. In support of the much more limited theory that gap junctions are related to the gamma oscillation, Hameroff quotes a number of studies from recent year.
From the point of view of consciousness theory, an essential feature of Penrose’s objective reduction is that the choice of states when objective reduction occurs is selected neither randomly, as are choices following measurement or decoherence, nor completely algorithmically. Rather, states are proposed to be selected by a ‘non-computable’ influence embedded in the fundamental level of spacetime geometry at the Planck scale.
Penrose claimed that such information is Platonic, representing pure mathematical truth, aesthetic and ethical values. More than two thousand years ago, the Greek philosopher Plato had proposed such pure values and forms, but in an abstract realm. Penrose placed the Platonic realm at the Planck scale. This relates to Penrose’s ideas concerning the three worlds: physical, mental, and the Platonic mathematical world. In his theory, the physical world can be seen as the external reality, the mental world as information processing in the brain and the Platonic world as the encryption, measurement, or geometry of fundamental spacetime that is claimed to support non-computational understanding.

To me it seems that Orch OR theory is more suitable for forming platonic representations of objects – that is invariant/ideal perception of an object. This I would relate to the Perceptual aspect of A-consciousness.

2. Electromagnetic theories of consciousness

The electromagnetic field theory of consciousness is a theory that says the electromagnetic field generated by the brain (measurable by ECoG) is the actual carrier of conscious experience.
The starting point for these theories is the fact that every time a neuron fires to generate an action potential and a postsynaptic potential in the next neuron down the line, it also generates a disturbance to the surrounding electromagnetic (EM) field. Information coded in neuron firing patterns is therefore reflected into the brain’s EM field. Locating consciousness in the brain’s EM field, rather than the neurons, has the advantage of neatly accounting for how information located in millions of neurons scattered throughout the brain can be unified into a single conscious experience (sometimes called the binding problem): the information is unified in the EM field. In this way EM field consciousness can be considered to be ‘joined-up information’.
However their generation by synchronous firing is not the only important characteristic of conscious electromagnetic fields — in Pockett’s original theory, spatial pattern is the defining feature of a conscious (as opposed to a non-conscious) field.
In McFadden’s cemi field theory, the brain’s global EM field modifies the electric charges across neural membranes and thereby influences the probability that particular neurons will fire, providing a feed-back loop that drives free will.

To me, the EM filed theories seem to be right on track regarding the fact that the EM filed itself may modify / affect the probabilities of firing of individual neurons and thus lead to free will or sense of agency by in some sense causing some neurons to fire over others. I believe we can model the agency aspect of A-consciousness and find neural substrates of the same in brain, using this approach.

3. Holonomic brain theory:

The holonomic brain theory, originated by psychologist Karl Pribram and initially developed in collaboration with physicist David Bohm, is a model for human cognition that is drastically different from conventionally accepted ideas: Pribram and Bohm posit a model of cognitive function as being guided by a matrix of neurological wave interference patterns situated temporally between holographic Gestalt perception and discrete, affective, quantum vectors derived from reward anticipation potentials.
Pribram was originally struck by the similarity of the hologram idea and Bohm’s idea of the implicate order in physics, and contacted him for collaboration. In particular, the fact that information about an image point is distributed throughout the hologram, such that each piece of the hologram contains some information about the entire image, seemed suggestive to Pribram about how the brain could encode memories.
According to Pribram, the tuning of wave frequency in cells of the primary visual cortex plays a role in visual imaging, while such tuning in the auditory system has been well established for decades[citation needed]. Pribram and colleagues also assert that similar tuning occurs in the somatosensory cortex.
Pribram distinguishes between propagative nerve impulses on the one hand, and slow potentials (hyperpolarizations, steep polarizations) that are essentially static. At this temporal interface, he indicates, the wave interferences form holographic patterns.

To me, the holnomic approach seems to be the phenomenon lying between gestalt perception and quantum vectors derived from reward-anticipation potentials or in simple English between the perception and agency components of A-consciousness. this is the Memory aspect of A-consciousness. The use of hologram used to store information as a model, the use of slow waves that are tuned to carry information, the use of this model to explain memory formation (including hyperpolarization etc) all point to the fact that this approach will be most successful in explaining the autobiographical memory that is assited wuith A-cosnciousness.

4. Quantum Mind:

The quantum mind hypothesis proposes that classical mechanics cannot fully explain consciousness and suggests that quantum mechanical phenomena such as quantum entanglement and superposition may play an important part in the brain’s function and could form the basis of an explanation of consciousness.
Recent papers by physicist, Gustav Bernroider, have indicated that he thinks that Bohm’s implicate-explicate structure can account for the relationship between neural processes and consciousness[7]. In a paper published in 2005 Bernroider elaborated his proposals for the physical basis of this process[8]. The main thrust of his paper was the argument that quantum coherence may be sustained in ion channels for long enough to be relevant for neural processes and the channels could be entangled with surrounding lipids and proteins and with other channels in the same membrane. Ion channels regulate the electrical potential across the axon membrane and thus play a central role in the brain’s information processing.
Bernroider uses this recently revealed structure to speculate about the possibility of quantum coherence in the ion channels. Bernroider and co-author Sisir Roy’s calculations suggested to them that the behaviour of the ions in the K channel could only be understood at the quantum level. Taking this as their starting point, they then ask whether the structure of the ion channel can be related to logic states. Further calculations lead them to suggest that the K+ ions and the oxygen atoms of the binding pockets are two quantum-entangled sub-systems, which they then equate to a quantum computational mapping. The ions that are destined to be expelled from the channel are proposed to encode information about the state of the oxygen atoms. It is further proposed the separate ion channels could be quantum entangled with one another.

To me, the quantum entanglement (or bond between different phenomenons)and the encoding of information about the state of the system in that entanglement seems all too similar to feelings as information about the emotional/bodily state. Thus, I propose that these quantum entanglements in these ion-channels may be the substrate that give rise to access to the state of the system, thus giving rise to feelings that is the feeling component of A-consciousness i.e access to one’s own emotional states.

5. Space-time theories of consciousness:

Space-time theories of consciousness have been advanced by Arthur Eddington, John Smythies and other scientists. The concept was also mentioned by Hermann Weyl who wrote that reality is a “…four-dimensional continuum which is neither ‘time’ nor ‘space’. Only the consciousness that passes on in one portion of this world experiences the detached piece which comes to meet it and passes behind it, as history, that is, as a process that is going forward in time and takes place in space”.
In 1953, CD Broad, in common with most authors in this field, proposed that there are two types of time, imaginary time measured in imaginary units (i) and real time measured on the real plane.
It can be seen that for any separation in 3D space there is a time at which the separation in 4D spacetime is zero. Similarly, if another coordinate axis is introduced called ‘real time’ that changes with imaginary time then historical events can also be no distance from a point. The combination of these result in the possibility of brain activity being at a point as well as being distributed in 3D space and time. This might allow the conscious individual to observe things, including whole movements, as if viewing them from a point.
Alex Green has developed an empirical theory of phenomenal consciousness that proposes that conscious experience can be described as a five-dimensional manifold. As in Broad’s hypothesis, space-time can contain vectors of zero length between two points in space and time because of an imaginary time coordinate. A 3D volume of brain activity over a short period of time would have the time extended geometric form of a conscious observation in 5D. Green considers imaginary time to be incompatible with the modern physical description of the world, and proposes that the imaginary time coordinate is a property of the observer and unobserved things (things governed by quantum mechanics), whereas the real time of general relativity is a property of observed things.
These space-time theories of consciousness are highly speculative but have features that their proponents consider attractive: every individual would be unique because they are a space-time path rather than an instantaneous object (i.e., the theories are non-fungible), and also because consciousness is a material thing so direct supervenience would apply. The possibility that conscious experience occupies a short period of time (the specious present) would mean that it can include movements and short words; these would not seem to be possible in a presentist interpretation of experience.
Theories of this type are also suggested by cosmology. The Wheeler-De Witt equation describes the quantum wave function of the universe (or more correctly, the multiverse).

To me, the space-time theories of consciousness that lead to observation/consciousness from a point in the 4d/5d space-time continuum seem to mirror the identity formation function of stage 5.This I relate to evaluation /deliberation aspect of A-consciousness.

6. Simulated Reality
 

In theoretical physics, digital physics holds the basic premise that the entire history of our universe is computable in some sense. The hypothesis was pioneered in Konrad Zuse’s book Rechnender Raum (translated by MIT into English as Calculating Space, 1970), which focuses on cellular automata. Juergen Schmidhuber suggested that the universe could be a Turing machine, because there is a very short program that outputs all possible programmes in an asymptotically optimal way. Other proponents include Edward Fredkin, Stephen Wolfram, and Nobel laureate Gerard ‘t Hooft. They hold that the apparently probabilistic nature of quantum physics is not incompatible with the notion of computability. A quantum version of digital physics has recently been proposed by Seth Lloyd. None of these suggestions has been developed into a workable physical theory.
It can be argued that the use of continua in physics constitutes a possible argument against the simulation of a physical universe. Removing the real numbers and uncountable infinities from physics would counter some of the objections noted above, and at least make computer simulation a possibility. However, digital physics must overcome these objections. For instance, cellular automata would appear to be a poor model for the non-locality of quantum mechanics.

To me the simulation argument is one model of us and the world- i.e we are living in a dream state/ simulation/ digital world where everything is synthetic/ predictable and computable. The alternative view of world as real, analog, continuous world where everything is creative / unpredictable and non-computable. One can , and should have both the models in mind – a simulated reality that is the world and a simulator that is oneself. Jagat mithya, brahma sach. World (simulation) is false, Brahma (creation) is true . Ability to see the world as both a fiction and a reality at the same time, as a fore laid stage and as a creative jazz at the same time leads to this sixth stage of consciousness the A-consciousness of an emergent conscious self that is distinct from mere body/brain. One can see oneself and others as actors acting as per their roles on the world’s stage; or as agents co-creating the reality.

That should be enough for today, but I am sure my astute readers will take this a notch further and propose two more theoretical approaches to consciousness and perhaps look for their neural substrates basde on teh remianing tow stages and componenets of A-consciousness..

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