Michael Gazzaniga will deliver a Series of Lectures in the University of Edinburgh in 2009-2010. He is a Professor of Psychology at the University of California, Santa Barbara, where he heads the SAGE Center for the Study of the Mind. He oversees an extensive and broad research programme investigating how the brain enables the mind.
In addition to his position in Santa Barbara, Professor Gazzaniga is also the Director of the Summer Institute in Cognitive Neuroscience, President of the Cognitive Neuroscience Institute, and is a member of the President's Council on Bioethics.
Abstracts of lectures
Lecture 1: What We Are
"I shall begin by considering what we are. What do we need to know about the human brain in order to discuss the weighty questions of free will, mental causation, morals, ethics, and the law? To understand anything from a biologic perspective we must place this effort in an evolutionary context, consider the nature of the organ that allows us to be asking these questions, and to the extent that we are able, determine how it works. The fundamental point that emerges out of this analysis is that much complexity is built into the brain and not just passed along as accumulated cultural behavior and knowledge from one generation to the next. It is this built-in complexity that enables us to discover the keys to how, ultimately, the mind constrains the brain and not the other way around. We will appreciate that our automatic brains are structured complex systems with particular skill sets and that ultimately our “I” story—the story of our own personal, phenomenal consciousness—is embodied in the brain’s network systems and not in outside forces compelling the brain into action."
Lecture 2: The Distributed Networks of Mind
"Our brains are organized in such a fashion that very little of the processing, which is to say neural work, goes on in our conscious minds. Any simple act, such as pointing to your nose, involves forming the desire to touch your nose, planning a motor response, gathering information about the location of your nose, calculating in a flash if you want to bring attention to your nose and so on. All that information is gathered and processed and leads to the desired action, and yet little or none of it is done consciously. Even more daunting is the fact that how the brain accomplishes such a simple task is utterly beyond scientific understanding at this point in time. While textbooks are full of knowledge about the specific neurons involved—the areas in the brain that are active during such specific actions and even areas known to be active with intention to act—no one knows how it actually works.
The neurologic ward proves to be a laboratory of immense richness, with each patient revealing secrets that when stitched together point to an understanding about how the brain is organized and how conscious experience—the ineffable state we long to preserve, alter and feed—emerges from neurons. Studying such patients reveals our brains are not organized in a hierarchical fashion, but rather are a massively parallel and distributed system. Understanding and appreciating this fact helps us on the journey to discover the importance of the concept of emergence, the idea that the whole produces a new kind of state that affects the separate individual elements that make it up. These novel states, or phenomenal experience, are the stuff of the self. Thus, understanding how the organization of the brain leads to emergent phenomenal states adds to the picture of what it means to have a self."
Lecture 3: The Interpreter
"The “interpreter” is the device we humans enjoy that provides us with the capacity to see the meanings behind patterns of our emotions, behavior and thoughts. This concept is central to understanding the relationship between our brain and our strong sense of self. In a way, it is the device that liberates us from our automatic ways spelled out in Lecture 1 and 2. The interpreter constructs the sense that there is a “me” arising out of the ongoing neuronal chatter in the brain and making all of life’s moment-to-moment decisions. Our compelling sense of being a unified self armed with volition, deployable attention and self-control is the handiwork of the interpreter, for it brings coherence to a brain that is actually a vastly parallel and distributed system. This view stands in contrast to much neuroscientific theorizing or existential musing about our unified, coherent nature. In most models of brain and cognitive mechanism, one can identify, as Marvin Minsky once said, “the box that makes all the decisions.”
Yet if modern neuroscience has taught us anything, it has taught us, as I said in Lecture 2, that our brain is a highly parallel and distributed system with literally millions of decisions being made simultaneously. There is simply no place within this sort of architecture from which a single decision system could operate. Instead, this parallel processing is producing an organism that looks like a self-motivated, morally coherent, decision-making and conscious entity. Indeed, understanding how it works will emerge from understanding the workings of the interpreter and the brain that enables it. Moreover, this understanding will allow us to rid ourselves of the homunculus problem once and for all, while, perhaps paradoxically, setting the stage for why “you” are to be held responsible for all of your actions."
Lecture 4: Free Yet Determined and Constrained
"With our new concept of the distributed self, the concept of free will is even more odd and, I have always thought, a misnomer. As Dan Dennett once asked, "Free from what?" We parents work all of our lives to raise our children not to be random, sporadic and impulsive, but to be directed, controlled and mature. We want their automatic brains to be well experienced in assessing the likely outcomes of behaviors. We want them to accumulate scenarios of how to behave in a moral and ethical way so that when they are given a new challenge, they have a context for a proper response. We want their decision-making brain to call upon a life's-worth of experience and training to do the right thing. We surely do not want our children to suddenly be free of all of this experience and education and to choose some wacky course of action that leads to personal disaster.
So what does free will mean? It has become a catchall term and means seveeral things. In many ways the concept is fundamental to human thought and societal institutions. For example, our system of justice is built on the idea that we are all practical reasoners, working in a normal brain environment to produce coherent and ethical behaviors. We are held to be personally responsible for those decisions. Questioning the core concept, free will, necessitates rethinking many cherished notions of human institutions.
Understanding how choice works in the brain and acknowledging the likelihood that the age-old notion of free will may be miscast does not necessitate abandoning the conviction that we have some degree of control over our actions. Instead, there remains the possibility that mental states may influence an agent’s actions via downward causation, or, that is, the potential for the whole to have an impact on the action of its parts. It is tempting to think (or hope) that downward causation means the mind mysteriously alters neuronal firing patterns or neurotransmitter release at the synapse, but making such a claim would be tantamount to reinserting the homunculus back into the equation. Instead, I argue that downward causation is a far more nuanced brand of causality that cannot be cast in terms of simple neural function. The mind constrains the brain, interacting with the environment in such a way that a limited repertoire of neural states may be called up for duty. Downward mental causation means control via constraint. The implications of this sort of causation are far-reaching. Indeed, most of those who argue for downward causation, and there have been many, feel the idea is central in the battle against the competing idea of exclusively upward causation, which is the basis of the simple minded determinism of modern reductionists.
Certainly though, downward causation does not mean our mental life is unconstrained by the physical world or that a free-floating self authoritatively and invisibly guides the intricate workings of the brain throughout each waking moment. Again, it does mean the inferences, appreciations, values and human desires we possess as a result of heredity or experience can interact in the mind and constrain neural function in a way that eludes description in purely neural terms. Within this context, mental causes have merit. Decisions about challenges from the environment can be executed in full force and constrain the upwardly causal impulses when necessary."
Lecture 5: The Social Brain
"Once the self emerges, look around. You are not alone; there are others—more than 6 billion of us now, up from 150 million in 200 BC. When agriculture was invented in 10,000 BC, there were only 4 million humans. Our species evolved in a social landscape that required our ancestors to think about the other guy and to adopt strategies that facilitated success in this social setting. Naturally, this led to an explosion of social processes, everything from the domestications of plants and animals in order to enable sedentary societies, to specialization of skills, to simple exchange of goods. Suddenly rules and knowledge of others’ minds became necessary, even indispensable. Indeed, a moral framework for assuring fairness and trust began to emerge.
Recent research on primates reveals that our social structures find their roots in primates. Apparently, we like to be policed! We want a third-party arbiter to stabilize the niche we live in so there is accountability for our actions. Macaca mulatta monkeys have police for this purpose. It is an example of an emergent property of a social group that feeds back to control the elements in the group that produced the property.
As group size grew, rules developed, rules that existed and continue to exist in the ether of a social group. When others are part of the equation, ideas emerge like the notion of personal responsibility, a concept that has no meaning if you are the only self/person in the world. In this way, the glue of social life was quickly constructed: norms were established and cheaters were punished. Relating to others in a fair way became selected for and what we now mistakenly attribute to religions and ideologies is actually built into our brains tens of thousands of years ago. Like the complexity that is built in for cognition, complexity for social process seems to emerge as well."
Lecture 6: We Are the Law
"Downward causation is the key concept upon which to build a foundation for a modern view of ethics and with it, a system of values and laws. We all tend to forget that we are the law in the sense that we make the rules as a function of our current societal and personal values. As the rationale for our values and beliefs change, so too can the laws we choose to live by.
Appreciating the mind/brain system as a downwardly causal system liberates one from a closed loop kind of determinism. Under closed loop determinism, the concept of personal responsibility becomes nonsensical. On the other hand, a downwardly causal system that responds to new information and discovery and that can learn social rules is adaptive. Moreover, since this downwardly causal system exists alongside billions of others, all of the ingredients for personal responsibility are present. The response of our legal system to the progress of neuroscience should, therefore, be both conservative and forward looking, preserving the concept of personal responsibility while cautiously updating other legal constructs and policies in instances when neuroscience provides compelling evidence for specific adjustments.
As for the rest of us—for these are truly questions that inspire deep thinking and occasional existential torment in each of us—well, we can cast aside our determinism-related anxieties. Contrary to common beliefs about scientific determinism, with all of its implications for futility of purpose and meaning, we see that we are everything but that. We are free at last."