Rodrigo Quian Quiroga, neuroscientist: “Forgetting is the essential characteristic of intelligence”

A thin line separates science fiction from reality. Sometimes, it is only a matter of time before the paths of fantasy and scientific research cross and blur their borders, says the neuroscientist. Rodrigo Quian Quiroga (Buenos Aires, 56 years old): “What was science fiction until a few years ago is now science.” But can machines be conscious as in 2001: a space odyssey? Is it feasible to achieve the immortality that is proposed Open your eyes? And manipulate memory, as in Total challenge? Quian Quiroga, graduate in Physics, ICREA professor and researcher in the group of Perception and Memory of the Hospital del Mar Research Institutejust published Things you would never believe. From science fiction to neuroscience (Debate, 2024), a work in which he reviews, regarding iconic films of the genre, this transition from fiction to real life through the great scientific advances of the time. “Origin either Total challenge They play with the idea of ​​implanting memory. And that was already done at MIT: [en ratones] They optically stimulate specific neurons and manage to implant a memory that is a false memory. It is a proof of concept,” she exemplifies.

The scientist is a specialist in the study of the neural mechanisms of memory and discovered the so-called concept neurons (or “Jennifer Aniston neurons”), nerve cells in the hippocampus that respond to specific concepts after an experiment carried out with photos of characters known: ”They reflect the conscious perception [de algo] and not the visual stimulus,” explains the researcher about a finding that he considers key in the construction of the individual. Lover of philosophy and privileged human without a cell phone — “I can afford not to have one. The cell phone kills those moments of boredom in which it seems that you are not doing anything, but, suddenly, you start to spin ideas and things come up that you didn't have” -, Quian Quiroga also takes the opportunity in his book to reframe some of the big questions of humanity about consciousness, sense of identity or free will. “The book is a hoax: it is not science fiction or neuroscience; It is a treatise on philosophy,” he admits with a laugh.

Ask. Channel 53. Neuron 2. What's going on there?

Answer. That was Jennifer Aniston's neuron. When we evaluate a patient with refractory epilepsy to undergo surgery [se detecta el área cerebral de donde viene la crisis y se extirpa], electrodes are placed inside the brain to identify where epileptic seizures come from. And that, for me, allows me to record neurons: what we do is we show photos to the patient and we see if any of the neurons we record respond to any of the photos we show. Once, with a patient in the United States, I saw that channel 53, neuron 2, responded to photos of Jennifer Aniston and nothing else.

Q. What is that neuron trying to tell you?

R. She is representing a concept, which is Jennifer Aniston, because she responds to any photo of her. It's not that she responds to a visual stimulus because she has light from here or there, because she has her hair this way… She responds to me, no matter what she shows. This was the first of many neurons that I found that respond to a concept. What we see is that there are neurons in the hippocampus, an area of ​​the brain that is key to memory, that respond to concepts and associations between concepts that are precisely the skeleton of the memories of our experiences. What I infer is that, if you did not have this type of neurons, you would be unable to encode memories. These neurons are key to recognizing the experiences you have with those concepts.

Q. Why do we remember some things and not others?

R. One of the first things that surprised me when I started getting into neuroscience is how little we remember. Our memory is based on remembering very little information and making a construction based on that. That's why we have false memories. We are always constructing a reality from very little information. The memory capacity of our brain is very limited. In each person, we tend to find neurons that are related to things that interest them and it is because they form memories for those things that interest them. That is to say, if my sister passes by here I will form a memory because she is my sister, but if another person passes by, I will not form a memory because I do not know her, I am not interested in remembering it. You tend to form memories of things that are familiar or emotionally salient, something that impacts you greatly, for better or worse.

Q. Do we need to forget?

R. Yes. I think that in our society we give a very exaggerated value to memory. We tend to confuse intelligence with memory and that has a lot of impact because that is how we are evaluated at school. We have this tendency to want to remember more because it gives us the impression that they see us better. And here come the surprises: the key to the functioning of human intelligence is not what we remember, but the amount we forget. I believe that forgetting defines human intelligence, it is the essential characteristic of intelligence.

Q. Because?

R. When you encode concepts you are forgetting details. By developing thinking based on concepts, I am leaving aside a lot of details and that allows me to make much more advanced associations. I believe that human intelligence is based on being able to extract what is essential, leave aside the details and think about thoughts. And that means forgetting. This level of abstraction is exclusive to humans and that is the great peculiarity of human memory.

“I don't see why something that is encoded by neurons can't be encoded by transistors.”

Q. Is that where machines cannot compete to surpass human intelligence?

R. I don't think there is a scientific barrier by which I can say that the machine will not be able to become like us, because I don't see why something that is encoded by neurons cannot be encoded by transistors. It's not that organic living matter with carbon has different properties than what you could implement in a circuit. But I believe that artificial intelligence (AI) is still very far from approaching human intelligence. There are advances that are extraordinary, but even so, they are not even close to human intelligence.

Q. Is there anything that, while still science fiction, worries you because it could become real?

R. What is most on everyone's lips is AI. But it doesn't worry me, it makes me curious. There are two big AI questions that fascinate me: one is whether we will ever get an AI to wake up, in the sense that it suddenly becomes aware of its own existence; and another question is whether we can one day get AI to develop what is called general intelligence. That is, you learn something in one context and apply it in a totally different context; It's that you go out on the street and something happens to you that has never happened to you in your life, but you know what to do because you have an idea; It's common sense: you make inferences, analogies… It's knowing how to behave in new situations. That is general intelligence and, until today, it is in its infancy in artificial intelligence.

Q. General intelligence is what separates us from machi
nes, then? You say that you see far from becoming more intelligent than humans.

R. You don't have to be blinded by things that shine. 25 years ago, we all said that chess was an impregnable barrier for a machine. And suddenly, Deep Blue beats Kasparov. And today there is no chess player in the world who is capable of beating a computer. So, in playing chess, the machine has surpassed us. But you can't use the rules you learn playing chess to solve a theorem, to write a report, or to recognize faces. That's what it's missing.

Q. Is understanding consciousness the great challenge of neuroscience?

R. We are already answering that question. The big question we asked ourselves a while ago was how the activity of neurons is capable of generating sensations: the sensation of pink, the sensation that I like something, of seeing you… And I think that question is somewhat answered. It is a philosophical fallacy, it is believing that there are two different things. The sensation of seeing you is nothing more nor less than the activity of neurons. Now the question has changed: the big question is what specific process in the human brain we have to copy for a machine to wake up. We don't know that.

Q. Another topic that the book touches on is dreams. What is the purpose of dreaming?

R. We do not know. When someone wants to give you a serious answer, they will tell you that it is an epiphenomenon: something that is a consequence that has no function. I resist accepting that because, sometimes, the constructions of dreams are so fabulous that thinking that they have no function intuitively does not close me. And on the other hand, you have a lot of evidence that we can be very creative during sleep: Paul McCartney dreamed of the song Yesterday and he wrote it when he woke up, for example. I believe that dreams strip you of reality and that triggers your creativity.

Paul McCartney dreamed of the song Yesterday and he wrote it when he woke up, for example. I believe that dreams strip you of reality and that triggers your creativity.”

Q. It also addresses free will from the film Minority Report. He says that “conscious decision is a consequence of unconscious processes in our brain.” So free will is an illusion? Do we have no real capacity to decide?

R. Yes, you have the ability to decide. The problem is that we have deeply rooted Cartesian dualism: thinking that the mind is something different from the brain. So, you say that we do not have the capacity to decide, but it is your brain that makes the decision, it is you. You imagine that there is something ethereal and magical, that you call the mind, that exercises its will and that makes its decision and that implements it through the brain. But where is that mind? What is the mind if all there is are neurons? The mind is the behavior of neurons. And the exercise of will is that you make decisions based on the activation of your neurons. Decisions are the result of the activity of neurons and the activity of neurons is a deterministic process: whether a neuron fires or not has to do with the stimuli it receives from other neurons or from the outside. The decision-making process is deterministic, it is predetermined, what happens is that it is so complex that it is as if it were not complex. So the fact that it is predetermined doesn't change anything because there is no one who can predict it because it is extremely complex.

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