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• Alfredo Pereira Jr

  19 May 2008 | 15:19

  Dear Hans:

  Many thanks for opening this new Forum.
  Like you, I have been thinking about the same issues for years and still believe we can make progress.
  I have posted several ideas on the concept of consciousness in this and other discussion groups; maybe it is time to try to put all them together, although I am afraid I have changed my mind about some.
  In this post I will try to make a very brief (and numbered) description of the structure of human consciousness, as it appears to be when one combines first-person, philosophical and scientific knowledge. After making this description, I will be better prepared to discuss Arnold’s definition.

  1) Sensory stimulation elicits distributed unconscious brain activity related to features of stimuli;

  2) There is an integration process ("binding") such that we do not become conscious of the features separatelly, but of selected groupings;

  3) The selected group of features that appears to consciousness at a given time interval is called “conscious content”;

  4) The appearance of the content is the beginning of a “conscious experience”, understood as the dynamical process by which a conscious subject interacts with the world;

  5) Conscious experiences involve neuromuscular circuits and feedback from the environment;

  6) [An important definition] One whole cycle composed by the formation of a conscious content and the related experience is called “conscious episode”;

  7) Conscious episodes occur in space and time. This space and time is the adaptive result of evolutionary coupling of stimuli, brain and body spaces and times [this multiplicity of spaces and times is for me the hardest conceptual issue];

  8) Conscious experiences and episodes are singular, and for this reason the first-person perspective does not reduce to the third-person perspective [not because one is scientific and the other is not, as some philosophers of mind have proposed].

  Well, these are the main features of the structure of human consciousness IMHO. I hope it helps with the discussion. Everybody agrees? Is there any disagreement? [If so, please refer to the number of the statement(s) you disagree with]

  Best Regards,

  Alfredo

• Arnold Trehub

  20 May 2008 | 14:56

  I want to add that the brief definition of consciousness that I proposed is based on a detailed theory of the human cognitive brain where the structure and dynamics of essential neuronal mechanisms and systems have been described and tested in computer simulations. See:

  http://www.people.umass.edu/trehub/

  In particular see:

  http://www.people.umass.edu/trehub/YCCOG828%20copy.pdf
  http://www.people.umass.edu/trehub/Revonsuo.pdf

  These publications are relevant to Bernard’s Global Workspace and to what Alfredo calls conscious episodes.

  Best,

  Arnold

• Hans Ricke

  26 May 2008 | 06:03

  Thank you Alfredo and Arnold,

  before I go into the points you brought up and the definitory statements you made, I will throw in a definition that I have circulated at the beginning of the ‘quest’, which was about four weeks before this years’s conference in Tucson.
  Here goes: ()Consciousness is (1)the phenomenon (2)that enables (3)human beings (4)to perceive (5)consciously.

  This definition was supposed to be understood not as my own proposal, because I do not feel qualified to propose one. If was meant to point out a few elements of a very short definition, that have a chance of general agreement.

  Basically I do not think we will end up with a definition like () ‘consciousness is’ in the near future. But what was I aiming at?

  (1) ‘the phenomenon’ points at the question wether consciousness is a real natural phenomenon, that can be subject of scientific investigation. This question is relevant because there seem to be relevant positions that deny this quality to consciousness and rather see it as an illusion or even as a delusion.
  (2) once we have agreed on granting this quality to consciousness, we can see what it ‘does’, what it provides us with, what its function is – that enables. That answer is pretty obvious: it enables us to be aware. Without it, we would not be aware of anything. This way of looking at it implies many things, one being defining consciousness via a synonym like awareness.
  (3) I want to confine the definition to human consciousness. Christof Koch did not like that, which I fully understand, because I agree that animals also have consciousness. I am refering to Nagel’s bat analogy and want to eliminate many notions that are as far reaching as the now popular panpsychism view. This restriction fulfills the sole purpose of making an agreement more likely to be achieved. If we can agree on human consciousness, we can maybe later agree on animal consciousness and panpsychism.
  (4) Focussing on perception brings up a question that for instance Alfredo and I do not agree on but I hope I can convince people on the advantage of my view: consciousness just means perception ( and no response to perception whatsoever ). Not just in the sense of sensory perception, because we also perceive thoughts and emotions, the whole inner world, rather in the most basic understanding of experience, observation, witnessing etc. This seems to be a good starting point and many researchers in ‘the field’ have even focussed on vision to make it a smaller object of research.
  (5) Uses consciousness as a variable, because it is well established that there are all kinds of perceptions, some conscious and other unconscious.
  Obviously this can be criticised as ‘circular’ like David Chalmers did. I think though with philosophy alone we will not get anywhere, so a little compromise due to practical considerations will not hurt too much. Moreover, Chalmers advocates the irreducability of consciousness. And how you will define something irreducible by not using synonyms or being somewhat circular?

  My suggestion is to start by describing what we are trying to adress first like it has been done in the tradtion of natural science.
  My suggestion also is to focus directly on the agreable aspects of consciousness, that is why I think Max Velman’s article is crucial, because he points out a rather wide range of what is generally agreed upon. I also think Peter Bieri’s question about which sense of consciousness we are working is crucial, because obviously there are several senses available and in my opinion not adressing exactly the same phenomenon.

  Finally from my experience with this kind of discussion I think a successful attempt to define the central term of a new science, the central object ôf inverstigation will go in several ‘rounds’. That means: first some basic agreements are made, then proceeding to other aspects and check how far the agreements hold, eventually go back to the beginning of the process, question again until the realm is explored and the main aspects of data that are availabe, the main theoretical statement have been related to the attempted definition.
  I call this going around the cake…
  Maybe we will not manage to get hold of the cherry any time soon, but a basic part of the cake itself will be good enough to really strive for a good terminology.

  Yours friendly
  Hans

• Alfredo Pereira Jr

  26 May 2008 | 07:00

  Dear Hans:

  We really have a disagreement. Let´s take advantage of it.
  If I was going to make a really basic definition that is both phenomenologically and physiologically sound, it would be:
  “Consciousness is the phenomenon that enables human beings to act voluntarily”.
  Phenomenologically, our conscious perceptions are always directed to a decision about action (and this is the only conceivable way to explain Max Velmans’ "projection").
  Physiologically, we should look for the closest correlates/mechanisms/analogies of consciousness in dynamical large-scale processes that influence motor cortex activity.
  In this approach, the formation of conscious perceptual content can be scientifically approached by means of Information Theory (classical and/or quantum). The content is an pattern in the brain that can be scientifically described as Informational Content (the inverse of Entropy in Statistical Thermodynamics; see e.g. the work of G.Tononi and collaborators).
  Of course, this kind of description is quantitative and does not capture the “qualitative” aspect of information (the “meaning”, as W. Freeman and C. Nunn called it).
  My argument is that such a meaning can only be defined with reference to the actions to be executed by the brain. For this reason, perceptual patterns are extremely dynamical (the rame rabbitt smelling the same carrot will never produce the same pattern in his olfactory system, as Freeman showed).
  Another conceptual issue that I have stressed is that consciousness refers both to a (perceptual) content and an experience (together forming conscious *episodes*). You cannot have real experience without some action.
  In summary, no matter how we begin we should arrive to a conception that contemplates both perception and action, with a methodological difference that beginning with voluntary action we remain closer to the scientific approach.

  Best Regards

  Alfredo Pereira Jr.

• Arnold Trehub

  26 May 2008 | 16:02

  Alfredo and Hans,

  Evolution has given humans (and possibly other creatures) the biological machinery to behave adaptively and thrive in a complex and uncertain world. In order for humans to behave adaptively in the real world, each of us must have within our brain a useful internal representation of this world from our unique egocentric perspective. This means that the human brain must contain a biophysical counterpart to some kind of a 3D coordinate system with an ego/self location as its fixed origin within which the salient features of the world are first represented and then perceived so that we can either execute or plan effective action. It seems to me that the spatiotemporal neuronal activity within this egocentric brain system is what constitutes what we call consciousness.

  Notice (1) this allows consciousness to be a primitive global event before the analytic processes of perception, and (2) it provides for an internal simulation of our physical environment that can be immediately decomposed and used by us to guide our actions. Alfredo asserts “You cannot have real experience without some action.” If I understand this correctly, I disagree that experience/consciousness necessarily entails action. While I agree with Alfredo that consciousness enables action, and I agree with Hans that consciousness enables perception, I also believe that consciousness can be dissociated from neuromuscular action and perception. My claim is that before we can perceive and before we can act adaptively we must have a transparent phenomenal experience of the world from our own egocentric perspective. My suggestion is that this latter state is the minimal definition of consciousness.

  What are the counter arguments?

  Best,

  Arnold

• Alfredo Pereira Jr

  26 May 2008 | 18:03

  Dear Arnold:

  You wrote: “My claim is that before we can perceive and before we can act adaptively we must have a transparent phenomenal experience of the world from our own egocentric perspective”

  Your idea (that we can have phenomenal experience “before” perceiving and acting) sounds like Kantian, but at the same time you state that it is an evolutionary adaptation and then escapes from the traditional argument against Kantian “apriorism”. Like Piaget’s, your position seems to bring the best of two different conceptual worlds, Kantian Transcendental Idealism and Darwinian biological evolutionary perspective.

  I cannot criticize the consistency of your position, but for the purpose of discussion let me make a question. During Slow Wave Sleep, we do not have (conscious) perceptions or actions. Do we still have “transparent phenomenal experience” with the egocentric perspective? If not, what happens to phenomenal experience during SWS?

  Best Regards,

  Alfredo

• Alfredo Pereira Jr

  26 May 2008 | 18:33

  Dear All:

  Seth et al. proposed the following list of “thirteen features of consciousness that require theoretical explanation”.

  Best

  Alfredo
  
  1 Consciousness is accompanied by irregular, low-amplitude, fast (12–70 Hz) electrical brain activity.
  2 Consciousness is associated with activity within the thalamocortical complex (the “dynamic core”), which is modulated by activity in subcortical areas.
  3 Consciousness involves distributed cortical activity related to conscious contents.
  4 Conscious scenes are unitary.
  5 Conscious scenes occur serially; only one conscious scene is experienced at a time.
  6 Conscious scenes are metastable and reflect rapidly adaptive discriminations in perception and memory. According to the TNGS, qualia are the discriminations entailed by the underlying neural activity.
  7 Conscious scenes comprise a wide multimodal range of contents and involve multimodal sensory binding.
  8 Conscious scenes have a focus/fringe structure; focal conscious contents are modulated by attention.
  9 Consciousness is subjective and private and is often attributed to an experiencing “self.”
  10 Conscious experience is reportable by humans, verbally and nonverbally.
  11 Consciousness accompanies various forms of learning. Even implicit learning initially requires consciousness of stimuli from which regularities are unconsciously developed.
  12 Conscious scenes have an allocentric character. They show intentionality, yet are shaped by egocentric frameworks.
  13 Consciousness is a necessary aspect of decision making and adaptive planning.

  Items 1–6 are in one degree or another susceptible to characterization by quantitative measurement. Items 7–13 are more readily understood through logical and qualitative analyses.

• Arnold Trehub

  26 May 2008 | 18:37

  Good question, Alfredo. During slow wave sleep we have no phenomenal experience because there is a reduction in diffuse arousal from the ascending reticular activating system (ARAS). A supra-threshold level of ARAS input to the brain system which constitutes our egocentric phenomenal experience (the retinoid system) is needed to maintain the autaptic-cell activity of our conscious experience. During REM sleep, however, there is sufficient arousal to the retinoid mechanisms and then we do have phenomenal experiences (dreams). Years ago, I did long sleep EEG recordings together with electromyographic recordings and confirmed (along with others) that the REM EEG normally went along with a concurrent inhibition of neuromuscular activity in the limbs. This makes adaptive sense in that it protects from behavioral accidents during violent dreams.

  Best,

  Arnold

• Alfredo Pereira Jr

  29 May 2008 | 12:54

  Dear Arnold:

  Many thanks for the answer.
  My first impression is that the mechanisms of SWS that you studied and succintly described here indicate that it is not possible to have phenomenal experience without perceiving and acting. Therefore, phenomenal experience cannot be considered as existing “before” perceiving and acting, but (inducing from the empirical findings) it seems to be precisely the result of the conjunction of perceiving and acting.
  In other words, the retinoid system considered as a biological structure may exist before perceptions and actions occur, but its proper function (consciousness) is activated only when the subject is perceiving and acting. Do you agree?

  Best

  Alfredo

• Anonymous

  29 May 2008 | 19:17

  Alfredo,

  You raise an important and subtle point. As I have previously suggested, the proper function of consciousness (an activated retinoid system) is to provide us with a transparent phenomenal experience of the world from a privileged egocentric perspective. My theoretical analysis suggests that our minimal phenomenal experience, the lowest level of consciousness (C1 in my recent CONCOG paper) is simply a primitive sense of 3D space surrounding the self-locus; i.e., no perceptual or sensory content. This means that in the transition from deep slow-wave sleep to wakefulness, consciousness is initially activated (by ARAS priming) before the subject perceives or acts. In the alert subject, the phenomenal content of consciousness is greatly enriched by the perception of exteroceptive and interoceptive neuronal projections into the egocentric space of the activated (conscious) retinoid system. Thus perception and action contribute to our basic experience of what is where in proper spatiotemporal register (properly bound) within the phenomenal volumetric world around our core self.

  But to get back to your last question, as you can see from the above comments, I do not agree that consciousness is activated only when the subject is perceiving or acting.

  Best,

  Arnold

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