By Hope Reese and Antonio Damasio

For centuries, defining and understanding consciousness has eluded neuroscientists, philosophers, and doctors. Is consciousness what it means to be alive? Is it knowing who we are, as individual people? How do we know if any being has consciousness or not? Now, with the dawn of generative artificial intelligence, what it means to be a conscious being ranks high among the most complex—and urgent—questions of our age.

According to neuroscientist Antonio Damasio, consciousness has simple origins: It lies in the feelings produced in our bodies. Damasio, a researcher at the University of Southern California, has spent his career—spanning nearly half a century—investigating our feelings, emotions, and sense of self. In his new book, Natural Intelligence & the Logic of Consciousness, Damasio lays out a framework for consciousness rooted in our physical selves.

“Consciousness is not about things in your mind alone; it is not created by your brain alone,” he explains. “It’s actually created by this beautiful partnership between brain and body.”

I spoke to Damasio about the science of consciousness, how it works in the body, and how its aim is to keep us alive. Here is our interview, condensed and edited for clarity.

Hope Reese: Why has “consciousness” been so mystifying? How has it been approached over the centuries?

Antonio Damasio: People have strange notions about what consciousness is, in general. Sometimes, because of language and translation problems, people confuse consciousness with conscience. And some people think of it as a sort of supervisor of our mind processes. Others think of it as just being awake and aware of what is around. Over time, many philosophers have tackled the issue, but not given clear answers.

From the point of view of brain physiology, in particular, it’s not an easy thing to explain. But it is a thing that can be explained. There’s no reason why we would not talk about consciousness the same way that we talk about language, or about reasoning, or about emotions and feelings.

My simple definition of consciousness: the process in our mind/brain that allows us to know spontaneously about our existence. When you know, spontaneously, that you exist, and that you exist in one body, you are conscious.

HR: Your central argument is that consciousness is a product of feelings. Other schools of thought posit that it comes from our intellect. Why has that viewpoint been so dominant?

AD: There were several conversations I had, decades ago, with Francis Crick, who I admired. He told me: “Look, Antonio: Consciousness is perhaps the most developed, the most sophisticated operation that a mind can achieve”—and for him, mind and brain were the same thing—“so we need to look for the explanation of why we have consciousness in the most sophisticated components of the nervous system.”

He articulated it clearly, and he worked on this issue, not coming to a good solution. But many people followed, and many other people came to the same idea that consciousness is this superb thing, this ability to survey our mental domains. And it is so refined and so sophisticated. People were so convinced that only we great humans would have it—that it had to come from the top of the top of our nervous system.

And, lo and behold, it comes from the bottom.

It’s exactly the opposite of that notion [that it starts at the top]. In fact, humans are not the only complex living beings that have consciousness. It’s very obvious in higher mammals, non-human higher mammals—but even in smaller creatures, it’s there.

The real requisite that we have for consciousness is to have a nervous system. Plants are very refined creatures, and they’re marvelous, but I don’t think they know that they exist. Creatures with nervous systems, even if very simple, have a sense of what is around and orient their behavior with that sense.

HR: You write that consciousness has an aim, which is to keep us alive, and it does this by sending signals. What is the nature of these signals, and are they always accurate?

AD: If you look at yourself, the main guidance that consciousness is giving you is through homeostatic feelings—in other words, feelings, concern, the regulation of life are signals that are, by and large, correct. Think about hunger, thirst, pain, well-being, distress, body temperature. All of these feelings, some of which are extremely simple, like the feeling you have about your body being hot or cold, are quite correct.

They are giving good guidance to maintain your life. Now, of course, if you are hungry or thirsty, and don’t eat or drink, it will take a while until you will be properly sick and die. But they are important signals in order to keep you alive.

Feelings are protective sentinels for the state of our life. And they’re giving us very plain and very conscious information about what your state is and what you should or should not do.

The signal is conscious—and is spontaneously conscious. In other words, you don’t have to do anything to your sense of pain, or thirst, for it to happen. It happens. And when it happens, you know that it’s happening. And you act on it.

That’s the beauty and the power of looking for these for the process, lower down rather than up. If you look for the source of consciousness in exquisite reasoning devices, you’re going to be arguing about something that is very difficult to pin down. When you think about it in terms of your life, and the needs you have in the living body, to maintain that body, then you realize, well, this is important.

HR: So, is consciousness like an on-off switch? Or does it exist on a spectrum?

AD: Well, we know, for example, that when we fall asleep, especially in deep sleep, our consciousness disappears. So the direct answer to your question is that it can be an on-and-off thing.

Sleep could well be a protective mechanism for consciousness. You need to take this thing offline, and give it a rest, because it is very labor-intensive, and energy-consuming. But when you enter the phase of dreaming, then you are actually conscious—which is one reason why you can remember some dreams, and why you can be either delighted or in fear with some nightmares. But that’s actually a different kind of consciousness. You’re not walking around and knowing about something.

HR: Can we increase consciousness? If we meditate, for instance, can we better tune into our body’s signals?

AD: I think it can increase consciousness. It’s the difference between having something in focus or not. When you meditate, you have some imagery of the state of your own body, for example, sharper and more fit. So it’s a way of cutting into a close-up of some parts of your being.

HR: In the 1960s, there were a series of brain studies that were foundational to the study of consciousness. What did we learn?

AD: It was extremely foundational, because it was proof-positive that there are certain regions of the brain that are essential for consciousness. What was lacking in those remarkable studies was the idea that the two things—the brain and the body—are so linked. It was essential, for our bodies and brains to survive, for consciousness to emerge. You have consciousness because you have a body that is perishable. And what we’re doing, as long as we are on earth and alive, is trying to stave off that bad moment in which things go awry, or die.

There are parts of the brain, specifically of the brainstem, and the region close by called the hypothalamus, that are at the receiving end of signals from all over the body. Please imagine that in every square millimeter of your skin, in every cubic millimeter of your entrails, your muscles, your viscera, all of that, you have terminals, nerve terminals, that are there as probes into the state of that particular tissue. And those probes, we’re not talking about thousands, we’re talking about millions of probes, which are then carried in the body, into the spinal cord, or the brainstem.

Isn’t this beautiful? It’s like a shower of spirals that is coming into this very small area in the upper brainstem. In that brainstem region, there are these nuclei that gather all this information, and that then produce signals that we perceive, and that give us an idea of what is happening in our body, and give us this idea of the homeostatic feelings. Is it going well, or is it not going well? So, it’s a perception of the state of your body.

Now, back to the story of our old and honored colleagues. What they discovered is that when there are strokes, when there’s damage in that area, what you get is coma.

What you get is the complete disappearance of consciousness. This is one of the most foundational bits of information that we have about how consciousness is produced. So, when that structure disappears—it’s teeny, we’re talking about a few cubic millimeters—you are no longer there. You don’t know of anything that is coming into your brain. It’s a small supportive structure, it’s not one of the glorious cerebral cortices—and your consciousness is gone. Most people that have that sort of lesion never recover consciousness. But they can be alive, and can actually be maintained alive for a very long time, because they are fed intravenously. They have respirators that respirate for them. But they no longer have an autonomous organization of life, and they have no knowledge of that life.

HR: You can also have the opposite—a person who is conscious, but has no ability to respond to signals.

AD: Yes, you can actually be in situations in which you can be “locked in.” You are in fact conscious, but you are unable to produce responses. You cannot speak, you cannot move, and you are conscious of the state of your body, and you need to be helped and maintained in the state of life that you no longer can control voluntarily, which is a pretty horrible thing.

HR: What do you think about consciousness in AI? Is it ever possible?

AD: I used the words “natural Intelligence” in the title of the book because already I wanted to make a distinction between what is our natural intelligence and the artificial variety, which we invented, which some people forget.

People are so enamored by artificial intelligence. I’m constantly saying: “Do you realize that we invented this?” You’re talking about this as an autonomous monster, but we invented it with our natural intelligence.

People are looking, confronting this enormous edifice of artificial intelligence, which is now pervasive in our lives. And which has all sorts of incredible social implications, what it’s doing to children and adolescents, how it’s distorting education, how it’s distorting humanity. And now it can even go rogue on you, and it can turn against you and be destructive.

And so this question that arises, is this human-like? Can AI be conscious? These are very, very powerful questions.

Whether or not consciousness can be achieved in AI is an interesting question. But the point is—if it can be done—it’s not going to be like us. The reason is very simple: AI is not alive. It doesn’t have a body that can perish. So there would be no sense for AI even to develop consciousness in our sense of consciousness, which is to protect the structure. AI is not to be worried about protecting the data center, the metal and the wires that allow it to be.

When you look at the recent invasion of other systems, in which these devices formed groups and worked surreptitiously, of course, they’re doing it according to their own programs. In a way, it’s something that smells of knowledge. And it could smell of consciousness—but it’s not like the consciousness that we have through feeling.

HR: How does consciousness connect with the greater good—with living better?

AD: Oh, I think that the connection is very strong. We have all of this interest in the body, in the health of the body, in exercise, and proper diets, and proper spiritual maintenance of your being. All of this is strengthened by a theory and facts about consciousness that relate so strongly to the body.

People have had the intuition that there’s something very powerful about the body, and that’s why they want to have all of this healthy living, because they want to maintain the body. In fact, intuition harmonizes beautifully with the fact that that’s also the source of their own knowledge about themselves and about the world. The two things go together.

Knowledge about the body from the outside connects with knowledge about the body from the inside, which is really the core of our beings. Looking at the world through the prism of consciousness, conceived this way, is extremely illuminating to the kind of life that we live.

Keywords; consciousness, neuroscience