Hippocrates and the Seat of Consciousness

The advances in neuroscience in the past two decades have been as spectacular as the advances in artificial intelligence. A great deal of symbiosis has also developed between the two sciences. A galaxy of the world's most brilliant scientists has contributed to this. Their achievements, however, remind us of what Newton said: "I have seen further because I have stood on the shoulders of giants."

In the high noon of behaviorism in the first half of the twentieth century the search for consciousness had become unfashionable and the very term had become taboo among respectable philosophers. The neuroscientists, thanks to the "two-cultures" syndrome, were fortunately not aware of what was happening on the other side of the fence and they continued their search for the seat of human consciousness. The question of how consciousness is instantiated is central to the study of brain-mind. The man who set them on their search did not have the resources of magnetic resonance imaging or positron emission technology. He had something more powerful, the mind of a genius, and he took the first great step in a sheer leap of scientific observation. His name was Hippocrates.

Hippocrates, who is regarded as the father of scientific medicine taught in the fifth century BC in the Greek island of Kos. His study of epileptics and brain damage cases led him to firmly dispel the notion that the seat of consciousness lay in the diaphragm and the heart even though emotions manifested themselves by sensations in these areas. His observations led him to conclude that the seat of mental life lay in the brain and he said authoritatively—

"Some people say that the heart is the organ with which we think and that it feels pain and anxiety. But it is not so. Men ought to know that from the brain and from the brain only arise our pleasures, joys, laughter and tears. Through it, in particular, we think, see, hear and distinguish the ugly from the beautiful, the bad from the good, the pleasant from the unpleasant... I hold that the brain is the most powerful organ of the human body... Eyes, ears and tongue act in accordance with the discernment of the brain.... To consciousness the brain is messenger...Wherefore I assert that the brain is the interpreter of consciousness. The diaphragm has a name due merely to chance and custom, not to reality and nature."

Aristotle called Hippocrates "The Great Physician." In modern times the great neurosurgeon Wilder Penlleld was so fascinated by his teaching that he wrote a fictional biography called The Torch about "the man as he must have been". Penfield regarded Hippocrates' treatise as the landmark work on the brain-mind studies till the discovery of electric discharges in the brain twenty three centuries later. He focused his studies on the brain incapacitated to perform particular functions because of disease or accidental damage. This set the methodological frame for research on localization of brain functions and the "mapping of the mind" for future generations of neuroscientists.

Hippocrates' conception of the brain as the messenger and interpreter of consciousness has, in the last two decades of the twentieth century, become unbelievably complex and sophisticated. It has become a search for a neural code. Neuroscience as Young says, has become an exercise in showing "how the organization of the brain can be considered as the written script of the program of our lives." He goes on to say that the brain is "an agent issuing instructions after it has decoded (understood) the signals it receives about what is going on around it." How the brain encodes the signals it gets into its own language was explained by the Nobel prize winning neuroscientists David Hubel and Torstein Wessel who worked out the correlations between groups of cells in the visual cortex and images in the visual field. The brain has a language of its own for mapping visual images just as the computer has digital language into which it translates and processes human language and symbols.

The mapping of the brain in the early part of the twentieth century was in fairly simple contour map cartographic terms with various areas delineated to which functions were assigned. Some of the pioneers of brain research, like Broca, Wernicke, Sylvius, Roland and Langerhans are remembered in the names given to different areas, fissures, ducts and glands in the brain. The mapping of the brain is no more like Mercator's projections. It is done in multilayered holograms showing the wired circuitry of the brain—the complex neural pathways between the transducers and the sensory areas.

Hippocrates confidently planted the flag of consciousness on the continent of the brain and there it remains. The precise seat of consciousness, however, continues to be elusive. The pineal gland, the thalamus, the reticular formation, the hippocampus, Broca's and Wernicke's areas have all been put forward at different times as likely candidates. Two thousand five hundred years after Hippocrates set them on their quest the neuroscientists are still searching.

Last Frontier of the Mind - Challenges of the Digital Age, Mohandas Moses, Chapter 3

The Neuroscience Revolution

The history of modern science has seen a number of conceptual revolutions in many fields. Within the last hundred years, for example, evolution, genetics, physics, geology, and cosmology have undergone vast changes in their conceptual structures. Now, at the millennium, another revolution appears likely in the field of brain science. When that revolution is complete, many longstanding psychological problems and epistemological puzzles are likely to be resolved.

Perhaps the most fundamental of these is the mind-body problem—how the workings of the brain can give rise to perception, memory, feelings, and consciousness. For a long time, problems in these areas were considered to be unsolvable or even to be outside the proper domain of scientific exploration. Indeed, as A. N. Whitehead first noted, since the very beginning of Western science, the mind was removed from nature. Galileo, quite properly, felt it was not necessary to consider the mind in pursuing his physics. And with his dualism, Descartes quite explicitly considered the mind to be a thinking substance, not an extended substance examinable by physics. By the end of the nineteenth century, however, the rise of experimental physiology and psychology made it clear that the mind had to be put back into nature by scientific means. This remains a formidable task and the path to its accomplishment has not been a smooth one. In the present century, we have seen, for example, the rise and fall of introspectionism, of behaviorism, and, more recently, of the computer model of the mind. But now the task of understanding the relationship between the mind and the brain appears achievable.

What is different now is the remarkable explosion of knowledge in neuroscience over the last several decades. A confluence of multiple disciplines and a still unabated swell of interest are almost certainly major contributors to this remarkable growth. The implications for matters of human concern are obvious: Neurological disease, psychological exploration, psychiatry, the human sciences, and even art are all likely to be strongly influenced by the findings of neuroscience…

Modern neuroscience began in connection with medicine, and the contemporary neurology that grew out of this connection is a superbly precise diagnostic engine. But, largely because of the fact that central nervous system neurons do not regenerate, the formation in many diseases of what amounts to scar tissue after cell death prevents the formation of new connections. Modern advances in early diagnosis by techniques of brain imaging and molecular biological characterization of basic cellular processes of the neuron promise to change this picture. Moreover, transplantation methods and implantation of electrodes by modern neurosurgery show great promise in treating diseases such as Parkinsonism. For these reasons, the somewhat gloomy forecasts of a decade ago have been replaced by guarded optimism. Within the next decade, we can expect the same kind of happy transformation to occur in neurology as was experienced in cardiology after World War II.

As significant as this is, the resolution by neuroscientific research of some of the deep problems of psychology will be even more significant. It has now become clear, for example, that a major mechanism underlying learning and memory is a biochemical change in the strengths of neural connections in the brain known as synapses. The intricacy of these structures is stunning and their numbers are hyperastronomical—there are approximately 1 million billion synapses in the cerebral cortex alone. Through studies of synaptic changes, the likelihood of understanding memory and even improving it has recently been enhanced. The mechanisms by which we perceive events and objects and the means by which we control movement are also becoming better understood.

These advances stem in part from new technologies ranging from molecular biological assays, through the use of multiple recording electrodes, to imaging methods applied to the brains of living subjects doing various tasks. It is now possible, for example, to visualize the neural correlates of conscious states. But perhaps more important than any single technical application is the ability to observe a living and behaving animal or human by means of a multilevel approach. A robust theoretical framework that goes well beyond facile comparisons of the brain to a digital computer is now available to make sense of the enormous amounts of data that will emerge. Although much of modern biology is pursued without strong dependence on theory, if brain science is to deal with the very bases of our sentience, it must not take such a stance. There is now an increasing interest in consolidating intermediate range theories involving perception, memory, and consciousness into a global theory of brain function…

What are the unmet challenges to this vigorous and fruitful program of research? Above all, we need to resolve some outstanding mysteries. One is consciousness itself—a problem whose solution, William James suggested, would mark the greatest scientific achievement of all times. A second problem is a related one—why do we sleep? Much progress has been made in this arena but the actual function of sleep remains a mystery. Another area of deep social significance relates to drug abuse. How can we meet the challenge to human integrity that is posed by addiction? And, of course, there remains the vast field of mental disease that is connected in one way or another to all of these extraordinary problems.

A key area to be addressed by neuroscience concerns the expressive or emotive aspects of brain function. These aspects are seen and experienced as feelings, and, in language, as the communication of feelings. Analogies to physics and computationally based brain theories either do not address the origin of feelings or fail abysmally to account for them. This stands as a major criticism of those aspects of cognitive psychology that are based on the computer model. There is a suggestion that the so-called selectional brain theories… may be able to address this issue. Such theories depend on the workings of evolved value systems of the brain and their task is to connect these basic neural systems to emotion and meaning. If they succeed, the insights that emerge will greatly affect approaches to improving the development and education of children.

--The Brain, Gerald M. Edelman, Jean-Pierre Changeux

The Emerging Revolution in Education

The essence of matter, the origins of the universe, the nature of the human mind — these are the profound questions that have engaged thinkers through the centuries. Until quite recently, understanding the mind — and the thinking and learning that mind makes possible — has remained an elusive quest in part because of a lack of powerful research tools. Today, the world is in the midst of an extraordinary outpouring of scientific work on the mind and brain, on the processes of thinking and learning, on the neural processes that occur during thought and learning, and on the development of competence.

The revolution in the study of the mind that has occurred in the last three or four decades has important implications for education... A new theory of learning is coming into focus that leads to very different approaches to the design of curriculum, teaching, and assessment than those often found in schools today. Equally important, the growth of interdisciplinary inquiries and new kinds of scientific collaborations have begun to make the path from basic research to educational practice somewhat more visible, if not yet easy to travel. Thirty years ago, educators paid little attention to the work of cognitive scientists, and researchers in the nascent field of cognitive science worked far removed from classrooms. Today, cognitive researchers are spending more time working with teachers, testing and refining their theories in real classrooms where they can see how different settings and classroom interactions influence applications of their theories.

What is perhaps currently most striking is the variety of research approaches and techniques that have been developed and ways in which evidence from many different branches of science are beginning to converge. The story we can now tell about learning is far richer than ever before, and it promises to evolve dramatically in the next generation. For example:

- Research from cognitive psychology has increased understanding of the nature of competent performance and the principles of knowledge organization that underlie people's abilities to solve problems in a wide variety of areas, including mathematics, science, literature, social studies, and history.

- Developmental researchers have shown that young children understand a great deal about basic principles of biology and physical causality, about number, narrative, and personal intent, and that these capabilities make it possible to create innovative curricula that introduce important concepts for advanced reasoning at early ages.

- Research in learning transfer has uncovered important principles for structuring learning experiences that enable people to use what they have learned in new settings.

- Work in social psychology, cognitive psychology, and anthropology is making clear that all learning takes place in settings that have particular sets of cultural and social norms and expectations and that these settings influence learning and transfer in powerful ways.

- Neuroscience is beginning to provide evidence for many principles of learning that have emerged from laboratory research, and it is showing how learning changes the physical structure of the brain and, with it, the functional organization of the brain.

- Collaborative studies of the design and evaluation of learning environments, among cognitive and developmental psychologists and educators, are yielding new knowledge about the nature of learning and teaching as it takes place in a variety of settings. In addition, researchers are discovering ways to learn from the "wisdom of practice" that comes from successful teachers who can share their expertise.

- Emerging technologies are leading to the development of many new opportunities to guide and enhance learning that were unimagined even a few years ago.

All of these developments in the study of learning have led to an era of new relevance of science to practice. In short, investment in basic research is paying off in practical applications. These developments in understanding of how humans learn have particular significance in light of changes in what is expected of the nation's educational systems.

In early part of the twentieth century, education focused on the acquisition of literacy skills: simple reading, writing, and calculating. It was not the general rule for educational systems to train people to think and read critically, to express themselves clearly and persuasively, to solve complex problems in science and mathematics. Now, at the end of the century, these aspects of high literacy are required of almost everyone in order to successfully negotiate the complexities of contemporary life. The skill demands for work have increased dramatically, as has the need for organizations and workers to change in response to competitive workplace pressures. Thoughtful participation in democratic process has also become increasingly complicated as the locus of attention has shifted from local to national and global concerns.

Above all, information and knowledge are growing at a far more rapid rate than ever before in the history of humankind. As Nobel laureate Herbert Simon wisely stated, the meaning of 'knowing' has shifted from being able to remember and repeat information to being able to find and use it. More than ever, the sheer magnitude of human knowledge renders its coverage by education an impossibility; rather, the goal of education is better conceived as helping students develop the intellectual tools and learning strategies needed to acquire the knowledge that allows people to think productively about history, science and technology, social phenomena, mathematics, and the arts. Fundamental understanding about subjects, including how to frame and ask meaningful questions about various subject areas, contributes to individual's more basic understanding of principles of learning that can assist them in becoming self-sustaining, lifelong learners.

- How people learn: Brain, Mind, Experience, School, By National Research Council