The philosopher William James called the relationship of brain to mind "the ultimate of ultimate problems". Neuroscientists who have looked at the problem have usually reduced it to two hypotheses—one, that the action of the brain explains the mind or two, that there are two elements: the brain and the mind. Sir Charles Sherrington said that "our being should consist of two fundamental elements offers, I suppose, no greater inherent improbability than that it should rest on one only." Lord Adrian who shared the Nobel Prize with him for work in neuroscience said in 1966 that "as soon as we let ourselves contemplate our own place in the picture we seem to be stepping outside the boundaries of natural science."
Sir Wilder Penfield however goes well beyond Lord Adrian and in probing the nature of the brain-mind, he put down his conclusions in a way which required great intellectual courage.
Wilder Penfield was one of the greatest neurosurgeons of the twentieth century. His account of how he began his exploration of the nature of brain-mind makes interesting reading— "While listening to the lectures of Sir Charles Sherrington as a medical student in Oxford, I realized that there was a thrilling undiscovered country to be explored in the mechanisms of the mammalian nervous system. Through it one might approach the mystery of the mind if only one could deal with the human brain as Sherrington had analyzed the reflexes of the animal brain. I have asked three distinguished friends from three different disciplines to join me in the enterprise: William Feindel, a neurosurgeon; Charles Hendel. a philosopher and Sir Charles Symonds, a neurologist." This sounds almost like the beginning of a John Buchanan thriller where Richard Hannay and his friends meet in the cozy atmosphere of a London club to track down an international conspiracy, except that here the quest was much more exciting, the nature of the human mind itself. In the book which ensued—The Mystery of the Mind (1975)—Penfield propounds the thesis, extremely courageous for a neuroseientist, that mind exists independent of brain.
Penfield concedes that the brain resembles a computer in many ways— in its integrative and coordinating action; in the functioning of the hippocampus with its keys of access to the record of the stream of consciousness and its ability to reactivate the store of memories and in the working of the interpretive cortex which makes possible the scanning and recall of experiential memory. He speaks of the automaton in the brain as "a tiling that makes use of the reflexes and the skills, inborn and acquired, that are housed in the computer. The automatic computer that is ever active within us, seems to be the most amazing of all biological computers". However he also points out that "the human automaton which replaces man when the highest brain mechanism is inactivated is a thing without the capacity to make completely new decisions. It is a thing without the capacity to form new memory records and a thing without that indefinable attribute, a sense of humour. The automaton is incapable of thrilling to the beauty of a sunset or of experiencing contentment, happiness, love, compassion. These like all awareness are functions of the mind."
Penfield conducted hundreds of operations on the brain and was an internationally renowned neurosurgeon. When the great Russian physicist Lev Landau suffered brain injury in a motor accident it was Penfield who was summoned all the way from Montreal to attend to him. Penfield did pioneering work in cerebral localization. His very deep study of neuro-anatomy at both the theoretical and practical levels lead him to conclude that the brain contains two elements— "an automatic human computer and the highest brain-mechanism which play interactive roles selectively inhibitory and purposeful." But on the question of whether this provides a complete explanation of the working of the mind he says, "After years of studying the emerging mechanism within the human brain, my own answer is 'no'. Mind comes into action and goes out of action with the highest brain mechanism, it is true. But the mind has energy. The form of that energy is different from that of neuronal potentials that travel the axon pathways..." He amplifies this statement in clinical terms when he says that "neuronal action begins in the highest brain mechanism. Here is the meeting of mind and brain. The psychico-physical frontier is here... It is clear that much is accomplished by automatic and reflex mechanisms. It is not to be accounted for by any neuronal mechanism that I can discover." He put the position even more categorically later when he said. "To suppose that consciousness or the mind has localisation is a failure to understand neurophysiology."
At the end of his remarkable book, Penfield pointed out that "a century of scientific progress has passed since Hughlings Jackson suggested that there were high levels of functional organization in the brain... Since his time various partially independent mechanisms have been identified and mapped in the cerebral cortex and the higher brain stem. None of them can explain the mind. The mind remains a mystery."
Last Frontier of the Mind - Challenges of the Digital Age, Mohandas Moses, Chapter 3