12. THE LIMITS OF INTERVENTION

As our understanding of the relationship between the mind and the brain grows, technologies based on this knowledge have profound implications for mental health. But even as it grows, our understanding is limited to a small fraction of the brain’s complexity. Is it possible from this limited viewpoint to judge the practical and ethical boundaries of future technologies?

DALAI LAMA: The preceding discussions seem to indicate that specific mental functions, conceptual and otherwise, are dependent on or are very closely related to specific regions, functions, and states of the brain. This being the case, as neurosciences and biomedical technology develop and progress, do you anticipate that it will be possible to modify the brain so that certain types of conceptual processes and mental states do not arise, or that others can be readily introduced or enhanced? Theoretically speaking, of course.

PATRICIA CHURCHLAND: It is very hard to speculate about what the future is going to be like. But I suppose if you really did know in great detail where and how everything was happening in the brain, then I guess you could intervene to change things that you wanted to change either directly or through some indirect intervention. I guess it might be less possible to do so through drugs than to do so directly, in terms of some sort of patterned electrical stimulation. We are talking about changing specific concepts—

DALAI LAMA: Or conceptual processes, not just thoughts.

PATRICIA CHURCHLAND: I see, then I suppose you might also do it by changing the genes and producing a brain that had certain kinds of circuits that we don’t now have.

DALAI LAMA: Is it your understanding that there is one discrete part of the brain that is principally responsible for a certain kind of mental state or function? Even if that is the case, that part would presumably not be capable of operating in isolation, but only in interrelationship with the remainder of the brain?

LARRY SQUARE: I think the neurosciences’ consensus now would be that higher brain states, particularly attitudes and ideas, are dependent upon very complex patterned activities in different parts of the brain. And so it would be very difficult to imagine how one could ever direct changes by intervention. Rather, the pattern in representing a certain thought or an idea has a certain stability to it. The brain has such patterns, and the best way to get to that pattern would be from a preceding pattern, which would be another leading thought, attitude, or idea.

ALLAN HOBSON: As a psychotherapist, I think it important here to distinguish the very robust evidence for physical interventions that modify vulnerability to disease—and the clearly established need therefore to develop rational treatments. But projecting into the future, I would agree with Larry Squire’s notion that the best way to change ideas is to change ideas. And it doesn’t seem likely, in my view, that in the foreseeable future we will have a physical way of isolating a particular ideational set and changing it, chemically for example. Nor do I think that is even desirable.

LEWIS JUDD: If you had such capability, you would not be warranted ethically to use it.

ALLAN HOBSON: Right. The point is that the system is clearly open to interventions of two distinctive kinds. One is a biological intervention, the other is a conceptual intervention. The human brain is really unique in that it has these apparently dual aspects which probably represent higher order complexities of the same structural/functional system.

LEWIS JUDD: No matter how capable we become, no matter with what finesse we might introduce specialized chemical agents, or at what patterned complexity we might introduce electrical stimuli or inject neurotransmitters, or enter certain genetic influences with fibroblast viral vectors and things like that, I doubt that we will ever be able to engineer any kind of intervention relating to a strategy of thinking. It will certainly never get to a point where we can be so specific that we could actually isolate, enhance, or eradicate ideas or concepts.

PATRICIA CHURCHLAND: I don’t think we know that we will never get to that point. It was probably only fifty years ago that people said that you will never be able to engineer any genetically new organism.

ALLAN HOBSON: That’s true.

LEWIS JUDD: I think it is remote. I don’t think intervention will ever be that specific or that geometrically detailed.

DALAI LAMA: Can you anticipate a time in the development of your science that you will be able, depending on your knowledge of an individual’s brain, to know whether this person will be hot-tempered or not, be very happy or depressed, or be intelligent or dull, purely in dependence upon your understanding of the brain?

ANTONIO DAMASIO: Theoretically, I think that is perfectly possible. It is not likely to happen in our lifetime, but theoretically, yes.

LEWIS JUDD: It certainly is within the realm of probability.

DALAI LAMA: As you continue to progress in the neurosciences, do you think it is possible that one day by investigating a person’s brain you will know what that person is thinking of at the moment?

PATRICIA CHURCHLAND: I think that is going to be very difficult for technical reasons, but not so difficult in principle, in theory.

ANTONIO DAMASIO: Theoretically possible, but rather unfeasible.

DALAI LAMA: But it is possible?

PATRICIA CHURCHLAND: Theoretically possible, but you would have to know not only what was going on in many parts of that person’s brain simultaneously and sequentially, but also something about the environment and quite a lot about that person’s history.

DALAI LAMA: Up to this time, what percentage of the functioning of the brain do we understand?

ROBERT LIVINGSTON: Half of 1 percent.

ANTONIO DAMASIO: I would say more than that.

LEWIS JUDD: I am not sure. I think we have barely scratched the surface.

PATRICIA CHURCHLAND: If you want to know how the neurons are put together in circuits in order to explain something like perception or being able to move appropriately, then we have got part of the story for those things, but we don’t really understand how the brain performs such functions in its characteristically integrative fashion.

LARRY SQUIRE: I think at the level of gross functions, we understand a lot. We can talk, as you have heard, about memory and about vision. But one test of our understanding would certainly be: Can we take any of these computations and put them into a computer so the computer can see or make a decision or talk or turn language into print without a helper. We cannot yet do any of those things. So, obviously, we don’t understand in any great detail how the brain is doing such things.

ANTONIO DAMASIO: That may be just not understanding the details. Half of 1 percent is really very little. I think that in terms of mechanisms we understand a bit more. If we can’t implement it on a machine, it doesn’t mean that we fail in understanding. There is a hardware problem that we obviously cannot possibly solve because it has to do with the evolution of biological systems. So maybe we understand a bit more than is reflected in our capability of implementing our understanding in machines.

LEWIS JUDD: But also, the more we understand, the more it is very clear what we really don’t know. You might say that there is an exponential increase in the absence of knowledge.