Revista Argentina
de Neurociencias

Consciousness and the Brain

Interview with Rodolfo Llinás

Conducted by Sérgio Strejilevich, MD

 

"The brain is not a sausage...it is more like a well tuned musical instrument". R. Llinás.

Llinás is one of the strongest defenders of the "cerebrality" of the human mind. For this reason, by comparing the human brain to a musical instrument, he makes a 180 degrees turnabout in his position, if we wish to be dramatic, from which it will be hard to extricate himself. It is not only a metaphorical question or a question of form. His thalamo-cortical theory of the human consciousness adapts easily and flexibly to this analogy, originating multiple possibilities for new models.

 Rodolfo Llinás, was born and graduated in medicine in Colombia, and is currently the Chairman of the Department of Physiology and Neurosciences of the School of Medicine of the New York University. He came to Buenos Aires for the World Congress of Neurology and delivered a high-impact lecture in the School of Medicine on his favorite theory, philosophy of the mind and other flavors. An audience composed for the most part by students of Exact Sciences witnessed as this researcher's histrionics survived to an "attack" by the clunky old projector of our School. It served as the basis for what we listened as a strong and direct bet on the biological theories of the mind and consciousness. Between this event and the congress, we pursued Llinás to discuss all these matters.

Click on the underlined text to see the explanation of some of the terms used in the interview.

See also: Who is Rodolfo Llinás, some of his selected publications and the author of the interview.


S. Strejilevich. You compared the operation of the brain with that of a musical instrument. Well then, but musical instruments have developed in intimate agreement with the manner that its sounds and tuning were set, and this led many times to dramatic changes in the form of playing them and in its performance. A classic example is that of the clavier the predecessor of the piano - before and after the "Well Tempered Clavier" composed by Bach. Could we play with the idea of changes in the configuration of the consciousness through the evolutionary process?

R. Llinás: I understand your question in two senses, structural and functional. Structurally we should understand that one cannot think that the human brain is different from the brain of the other vertebrates. It is an important question, because we can investigate what is the difference between the brain of a mouse and ours, and of course the difference is enormous, in size and capacity. But if we look at the microscopic anatomy of a system such as the thalamo-cortical system (which generates consciousness) the difference disappears, because they have the same types of cells in both cases. Then we know that the difference exists in the complexity of the circuits, but not necessarily in its general architecture (shacks as well palaces as have a roof!). But if we look at the function, the situation is different. The brain, similarly to musical instruments, has great emergent properties. Remember that there used to be strings that one could not play in the old strings instruments, called "sympathetic chords", which were inside the instrument. I have suggested that this has happened inside the brain when it evolved. There is an enormous number of "sympathetic" chords that increase the cerebral capacity and that make our internal resonances more complex. This is the richness of the human brain, because the specific areas of the cerebral cortex are possibly the same in a monkey and in the human being, but the sympathetic chords are not. The association cortex, the indirect connections, are the features which really make us different from other animals. In particular, the capacity to imagine new things (our ideas or imaginations) of pieces of things, or of properties of the external world, is that allows us to invent things that don't exist. We began by using bones of animals as weapons and by using the same process we got to invent the television or the space satellites.

S.A.S.: Very well, but those same characteristics that you assign to us would give a greater flexibility to the human brain in relation to the way of organizing these emergent properties. But leaving the musical analogy apart, for example, J. Jaynes in "The Origins of Consciousness in the Breakdown of the Bicameral Mind " proposes that our consciousness, before the Greek culture, was organized in such way that the people truly dialogued with their own voices. Will we be able in the future to organize in a different way our conscious instrument?

R. Llinás: The different political systems, religions and social habits demonstrate that the same brain can be tuned in different manners. But the tuning capacity is limited. We can never feel as a jaguar, for example. We can imagine a man who believes or who intends to be a jaguar, but to intend is not the same as to be. We can have other ideologies, but we will continue restricted by the nature of our brain and of our body.

S.A.S.: You mentioned in your lecture the fact that consciousness seems to result in some way from an interaction between the thalamo-cortical scanning activity and the incoming stimuli from the environment. If we explore in more depth this proposal, we could get explanatory models for the action of some psychoactive drugs. For example, we could say that neuroleptics act as filters or "gates", impeding the generation of those interactions or resonances that could be present in the structure of some psychotic symptoms. What possibility do you see in these analogies?

R. Llinás: Definitely this seems to be the reality. And that not only from the point of view of neuroleptics, where the thalamo-cortical function can be changed, in the sense of "let's play another music" which is in better agreement with the external world (cheerful when it is sunny, sad when it rains) and not the continually sad music of the depressive or the continually cheerful music of the maniac. Besides, it changes in the parkinsonian or in the individual who has epilepsy of the "petit mal" type, also called epileptic absence. About this we know enough. We have discovered a large part of the biophysics of this type of activity in terms of its neural basis.

S.A.S.: What role would you ascribe to memory as an underlying mechanism of consciousness?

R. Llinás: Well, that is a different situation. Here we no longer see the evolution of the nervous system, but that of a certain individual. The role of the memory is very important but... not as important as we believe. Most of the important things that we do don't depend on memory. To hear, to see, to touch, to feel happiness and pain; these are functions which are independent of memory; it is an a priori thing. Thus, for me, what memory does is to modify that a priori thing, and this it does in a very profound way. But we cannot learn how not to recognize the differences between green and red. What we can learn is to change its sensibility (for example, that orange color is too red to paint an orange fruit) or its meaning (red, stop; green, proceed). We are two-legged omnivorous animals, and this means that we have many ecological niches, regarding the possible places where we can live. Therefore, we have to adapt to these different environments and we cannot predict, in a generic way, in which type of world we are going to live (cold as the North Pole or hot as Congo). Those parameters, which are the ones that change in the external world, give us the indication what type of memories we should have (for example, a seal should be killed with a harpoon and a tiger with an arrow). The most precious example is that of the phonemes of the human language. Everyone of us was born with the capacity to understand and to speak all and any of the human languages, but as time passes, we simply specialize in one or a few languages, and are unable to hear some phonemes of other languages (the boy who learned how to speak only in Japanese or Chinese, when he becomes adult is unable to hear the difference between "L"s and "R"s and they say "clazy" instead of "crazy").

S.A.S.: Since we spoke about language, do you believe that its evident "narrative" style is a fundamental part of consciousness? To what extent does the peculiarity of the human linguistic module in generating continuously inferences about facts participate in the structure of our consciousness?

R. Llinás: Language changes only those aspects of our consciousness which are based on information, but not the feelings themselves. The words are as stones that can cause wounds or as caresses that becalm and that guide us, but the content of consciousness is intrinsic. It is the same as with a suite of playing cards: we have a finite number of cards, but we can combine them and produce an infinite number of hands, but the "ace of hearts" will always be an "ace of hearts". The values don't change, only the place where we place them.

S.A.S.: Are the instinctive theories of language in the line of Chomsky's or Pinker's well adjusted to your ideas and do they contribute in some way to them?

R. Llinás: Chomsky is a good friend of mine, and in spite of this, I agree with many of his ideas. In particular, the idea of functional modules in the brain and its genetic pre-specification is in accordance to what I think.

S.A.S.: You recently wrote a book with Patricia Smith Churchland titled "The Mind-Brain Continuum". Do you believe that there is somehow a "remodeling" of the Cartesian dualism when one thinks about these subjects in terms of mind-brain relationships?

R. Llinás: The book is actually a collection of papers, but the title "mind-brain continuum" was suggested by me, because all its authors are cradle-to-grave monists, just like me.

S.A.S.: How emergent properties fit in this landscape?

R. Llinás: They don't present any problem. Emergent properties are what we usually call physics. Atoms combine among themselves and produce water; cells combine among themselves and produce the brain.

S.A.S.: You surely know Daniel Dennett's works. What opinion deserve the mind models proposed by this philosopher?

R. Llinás: In fact, I know him well and personally. Dennett has fallen in love with artificial intelligence and I think that the content of his books doesn't deserve the titles that he gave them. When he says to me "Consciousness Explained", I will think that, in exchange for a certain amount of money and some hours of reading, Dennett will give me an explanation, but the only thing that he tells me is "what I don't know". That book should be called "Consciousness Unexplained" or " How to Bore the Public ".

S.A.S.: Since we have touched the topic of artificial intelligence: do you believe that the contact between the human brain and computers, and the virtual spaces generated by them are gradually modifying our consciousness?

R Llinás: Definitely. To such an extent that some people prefer to see the game in the television than to go to the stadium. With virtual reality this will go to be worse, but at the end the "real" reality will win, because a virtual meal is not the same thing as a real one!

S.A.S.: How do you believe that this restructuring of the "concept of ourselves", which implies a greater knowledge about the mechanisms of consciousness will have a broad impact the social relationships, political structures, etc.?

R. Llinás: This is a very important issue. Imagine if we didn't have a soul, that there exists no heaven and no hell. Then, how could we appreciate life and why would we respect it? However, there are some people who don't respect it, even when they accept that life has a "second chapter" after earthly existence. But, what if this doesn't exist? I believe that we would be better individuals; we would appreciate life more, we would respect it more. This is my point of view.

S.A.S.: How could we reconcile the fact that, at least in the case of the United States, all those progresses in the concepts and philosophical-scientific knowledge about our brain and consciousness are accompanied by an important increase in the belief on mystic and religious ideas by the public in general?

R. Llinás: I think that this increase in the interest for mystic ideas has something to do with a dichotomy between the well-educated and the not well-educated groups. The well-educated people have less desire for magic solutions than the not so well educated. But the speed of generation of new knowledge is so high that for many people it seems much easier to hide behind something that solves everything, than to have to try to fight with the knowledge that has been growing in an incredible way. For this reason, I think that is some kind of social defense. Now, I don't know what will be the end of this seesaw movement. I have been hearing that the 21st century will be religious or not... I don't know.

S.A.S.: At least in psychiatry this is producing already what we could call "the consequences of the Cartesian thought for the clinic". For example, patients who are submitted to lithium therapy suffer from important subjective ruptures when they try to reconcile the incredible effect of this metal with their paradigms concerning themselves. Wouldn't possibly this situation being helped by a certain ideological delay on the part of the clinical neuroscientists?

R. Llinás: Yes, above all in psychiatry. There are powerful schools in psychiatry which do not wish the changes to happen. It is a pity, because many of them are dying off due to this absence of changes, and biological psychiatry is increasing in an exponential way. Psychiatry branches with a psychotherapeutical bent are already dying out, and I believe that the professionals who are practicing psychotherapy should know that sometimes a word to the patient is equivalent to an injection of a drug. What we have to do is to translate the meanings of these words and those ideas into concepts, which are more concretely related to the Neurosciences.

S.A.S.: Why do you think that we have to develop more neuroscientific knowledge in Latin American countries?

R. Llinás: The future of human relationships will be directly related to the cerebral functions. For this reason it is already a fundamental thing. In the past, and well until today, some South American countries have had a great neuropharmacological history, since the natives' times. It is necessary that we remind ourselves of the many licit and illicit drugs that were generated in our continent and that act on the brain. We have to remember the incredible histories with coffee, chocolate, etc. On the other hand, the Neurosciences do not exist exclusively to understand man's nature. They also serve a social function, such as in the treatment of the cerebral diseases or when helping us to have a more pleasant and constructive life. It is a thing that one could explore well.


Glossary

The following is an explanation of several of the words, concepts, institutions and words used in this interview. Additional pointers to resources available on the Internet are given, so that the interested reader may explore them further.

A priori
A thing or concept which exists before the one we are considering; also: an intrinsic, integral or inherent component of something. In Latin: "from former"
Artificial Intelligence
A branch of computer sciences which studies the theory and practice of artificial systems that imitate human perception and reasoning in a machine. Many are based on the formal grammar theories developed by Chomsky. See the AI's FAQs
Association cortex
Parts of the cerebral cortex which receive input from the sensorial cortices (vision, hearing, etc.) and which associate, integrate and process them in higher order mental functions.
Biological Psychiatry
A branch of psychiatry which studies mental disorders from the point of view of biological (neural and hormonal) causation, and treat them accordingly. See the Society of Biological Psychiatry home page
Cartesian dualism
It refers to the philosophical position championed by René Descartes (1596-1650), French mathematician and philosopher, which states that brain and mind are two distinct and irreducible principles, and that mind cannot be explained by the brain alone. See: Brain Project's Extracts from René Descartes' Philosophical Analysis of the Mind and the Brain.
Cerebral cortex
The part of the brain which covers the two hemispheres of the encephalon. It is composed by a thin and convoluted layer of gray matter (a high proportion of cell bodies). In higher vertebrates and in humans it is responsible for voluntary motor control, perception of most of the senses, cognition, and many other so-called higher functions of the brain. See "The External Architecture of the Brain" (Brain & Mind Magazine)
Chomsky
Noam Chomsky (1928- ), renowned American intellectual, MIT professor and linguist, who proposed theories of organization and representation of language. He revolutionized the study of languages with his theory of generative grammars. See his official home page
 "Consciousness Explained"
The title of a bestseller book by author Daniel Dennett, which discusses theories of consciousness and how they relate to the mind, from the point of view of the cognitive sciences. See the book advertisement
Daniel Dennett
Daniel Dennett is Distinguished Professor of Arts and Sciences and Director of the Center for Cognitive Studies at Tufts University in Massachusetts. He is a leading contemporary author and wrote two bestseller books, Consciousness Explained (1993) and Darwin's Dangerous Idea (1996). See his official home page.
Emergent properties
The term refers to properties or behaviors which arise in a system as a result of the interactions among its constituent elements, thus being more than the simple sum of individual contributions. For example, computation is an emergent property of neural networks. Complex systems usually show emergent properties. See On Complexly Organised Systems and Consciousness, by Stephen Jones (The Brain Project)
Lithium Therapy
Lithium carbonate salts have been introduced succesfully to treat depressive and manic depressive disorders. Its main use is to control mania and stabilize mood swings. See Pendulum's Resources: Lithium Therapy
Monists
Used by Llinás as the opposite of  "dualists", i.e., those who defend the Cartesian dualism hypothesis. Modern monists believe in a brain-mind continuum, and that behavior, the mind and its properties and manifestations are nothing more than the expression of a complex biological system. i.e., the nervous system. However, monism refers more properly to a philosophical school started in the 18th century which believes that all phenomena may be explained by one unifying principle or as the manifestation of a single substance (mind, energy, deity, etc.). See the Internet Encyclopaedia of Philosophy
Neuroleptics
Chemical substances which have an affinity for, or action on the nervous system. In Greek: "nerve seizing".
Parkinsonian
A person who suffers from Parkinson's disease, a progressive neurodegenerative disorder characterized by lesions on certain regions of the brain which control movement (basal ganglia). See Harvard University Parkinson's Web
Patricia Smith Churchland
A philosopher and renowned author of many books specializing on  "neurophilosophy", i.e., philosophical matters related to the current knowledge amassed by the neurosciences and its relation to cognitive sciences, artificial intelligence, etc. See her official home page
Petit mal epilepsy
A form of nervous seizures, characterized by frequent but transient lapses of consciousness and only rare spasms or falling. It occurs mainly in children and adolescents. In French: "small disease"
Pinker
Steven Pinker, a MIT psychologist and professor (Department of Brain and Cognitive Sciences), specializing in empirical studies of linguistic behavior and theoretical analyses of the nature of language and its relation to mind and brain. He is the celebrated author of a bestseller, "The Language Instinct". See his official home page
Psychoactive drugs
Chemical substances which act on the brain and affect behavior and the mind. They are usually employed to treat mental or psychic disorders and dysfunctions, but may be also used as substances of abuse.
Thalamo-cortical system
A functional and anatomical system in the brain, responsible for the interaction between sensory stimuli coming from the peripheral organs and the cortex (primary and associational). Among its many functions, current hypothesis ascribe to it a fundamental role in the maintenance and control of the states of arousal, awareness, sleep, dreaming and consciousness.
Virtual Reality
An immersive computerized interface system which creates a highly realistic interactive environment by means of stereoscopic visual displays with computer-generated imagery and sensors for head and hand position and movement; coupled together by special software. See Yahoo's VR section

Other articles: Consciousness. Jorge Martins de Oliveira, MD, Brain & Mind Magazine.


Who is Rodolfo Llinás

Dr. Rodolfo Llinas, MD, PhD, is the Thomas and Suzanne Murphy Professor in Neuroscience of the New York University School of Medicine. He received his medical education at the Universidad Javeriana, in Bogota, Colombia (1959) and his graduate education (Ph.D in Neuroscience) at the Australian National University, in Canberra (1965), under the supervision of John Eccles (Nobel prize in Medicine in Physiology). Dr. Llinas was a also postdoctoral research fellow in the Stanley Cobb Laboratory, Massachusetts General Hospital, Harvard Medical School from 1960-61. He held a NIH Postdoctoral Fellowship while working in the Department of Physiology of the University of Minnesota, 1961-63, and was a Research Scholar in the Department of Physiology of the Institute of Advanced Studies at the Australian National University from 1963-65. The MEDLINE bibliographical database lists 212 research papers bearing his authorship, on May 1998.

Dr Llinás research pertains mostly to neuroscience from the molecular to the cognitive level:

Home Page of Rodolfo Linás: http://www.med.nyu.edu/people/R.Llinas.html

Representative Publications


The Author

Sergio Strejilevich, MD. Psychiatrist, Coordinator of "Equipo de Investigaciones Clínicas del Servicio de Psicopatología del Hospital Parmenio Piñero de Buenos Aires" and Co-Director of RAN, Argentina magazine of Neuroscience


Translated from Spanish and Glossary written by Renato M.E. Sabbatini, PhD, Associate Editor, Brain & Mind Magazine.