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Roberto Lent

Roberto Lent: An expert in connections

Neuroscientist at UFRJ examines the versatile communication between neurons and proposes new ways to use science to improve education

Léo Ramos ChavesFor almost 40 years, neuroscientist Roberto Lent has been studying the formation and reorganization of connections among different areas in the brain. More recently, he began to encourage a different kind of interaction: interaction between researchers, entrepreneurs and educators, in order to create knowledge that enhances learning strategies and to quickly deliver this knowledge to teachers and students in the classroom. He hopes that development of this area, the so-called “science of learning,” will contribute to more quickly raising the educational level of Brazilian children and adolescents.

The son of parasitologist Herman Lent, who conducted research on the insects that transmit Chagas Disease, and chemist Maria Gregória Rivarola, Roberto Lent was born in Rio de Janeiro in 1948 and grew up knowing that he wanted to work with science. He entered the School of Medicine at the Federal University of Rio de Janeiro (UFRJ) in 1967 intending to work in genetics, the field of science then in vogue, but an internship at the start of his course led him to change his mind. He began his Master’s degree work while still an undergraduate, investigating neuroplasticity, or the capacity of cerebral connections to change, in the visual systems of skunks.

Lent later came to specialize in agenesis of the corpus callosum, a congenital malformation in the brain that prevents the exchange of information between the two hemispheres and thus hinders development. Together with neuroscientist Fernanda Tovar-Moll, a researcher at UFRJ and at the D’Or Institute for Research and Education, he discovered that the brains of people with this problem establish alternative communication routes between the two hemispheres.  However, his best known scientific work deals with counting cerebral neurons, and has led to a rethinking of some ideas in the field of neuroscience.

As someone who educates the general public about science, he participated in the founding of the magazine Ciência Hoje [Science Today] in the 1980s and wrote a series of children’s books entitled As aventuras do neurônio lembrador [The adventures of a neuron that remembers] (Vieira & Lent) that was later adapted for the theater. Married to publisher Cilene Vieira and the father of four, Lent received Pesquisa FAPESP at his laboratory at UFRJ and spoke of his role as the articulator of a national research network on the science of learning, and about other projects.

Educational background
Undergraduate degree in medicine (1972), Master’s (1973), and Doctorate in Biophysics (1978) from the Federal University of Rio de Janeiro
Federal University of Rio de Janeiro
Scientific production
87 articles published; advisor to 17 master’s degree candidates 17 phd degree students

What is your main project right now?
For four years now, I have been fascinated by the science of learning. Many people confuse this with the teaching of science, or scientific reporting, but it’s different. It is research that is inspired by education. It can refer to research on memory, neuroplasticity, and synaptic transmission, learning to read and write and learning disorders. There is room for basic science and for product development, such as videogames that aid learning. The goal is to increase knowledge about the most efficient ways to teach and to transfer this knowledge to the classroom. Therefore, it is a kind of translational research, which consists of accelerating the transfer of the results of basic research for application in education.

How did you become interested in the science of learning?
Even though I never practiced medicine, I always worked with topics related to health, thinking of their applicability. This viewpoint is grounded in the work of two advisors to the U.S. Government who created the panorama of translational research in the United States. One of them was Vannevar Bush [1890-1974], an engineer who directed the Office of Scientific Research and Development, and who, right after the end of World War II, wrote a report that became famous, proposing that the United States enter the field of translational research, then called applied research, but without abandoning basic research. The other was U.S. political scientist Donald Stokes [1927-1997], author of the book Pasteur’s Quadrant (see Pesquisa FAPESP Issue no. 110). At the end of the 1990s, he said that translational research would not be a straight line from basic research to innovation, but instead, a two-dimensional grid, with one axis measuring the social utility of the research, and the other axis evaluating how innovative it was and whether it added fundamental concepts to science. If research meets these two requirements, it is more profitable from a social viewpoint. In the field of health, this has been applied for decades, and as a result, infant mortality has fallen, many diseases have become curable and life expectancy has increased. I grew up with this idea in mind, and at the beginning of 2014, Jorge Guimarães, then president of Capes (Brazilian Federal Agency for the Support and Evaluation of Graduate Education, of the Ministry of Education, or MEC), asked me to attend a symposium on the science of learning in Shanghai, China. I was to give a presentation on my work and represent the MEC. I was surprised that there were few countries represented at the symposium: Australia, the United States and China, as well as Hong Kong. I realized that translational research focused on education could open up new horizons. Moreover, it had everything to do with my work with neuroplasticity, because learning depends on the capacity of the brain to change itself and create memories. When I returned, I began to read about this topic and I noted the window of opportunity it would represent for Brazil. Several universities work in this area, but there are almost no countries that have public policies and structuring measures for education. In Brazil, the CNPq [National Council for Scientific and Technological Development] has issued requests for proposals to encourage studies on several diseases, but not for education. This is why I decided to found the National Science of Learning Network.

What are the assumptions of the Network?
There is a set of actions that everyone agrees that would improve education in Brazil: raise teacher salaries, improve schools, extend the length of the school day, require teachers to pursue their profession full time, provide access to books, etc. These measures produce results, but they are not enough to improve the quality of teaching to the point of reducing the enormous gap between the educational level in Brazil and in the more developed countries. I calculated the amount of time that would be necessary for Brazilian students to reach the average score of the 72 countries evaluated in the PISA (Program for International Student Assessment) exam, administered by the OECD (Organization for Economic Co-operation and Development), which measures reading ability and knowledge of science and math among young people in high school. Brazil occupies one of the 10 lowest positions in the ranking prepared from this test. If the rate of improvement in education during the last 12 years is maintained, Brazil would not reach the average of the OECD exam until 2060. My proposal is that if we adopt scientifically proven measures to improve teaching, there is a greater chance of increasing the slope of this growth curve and reaching the OECD average sooner, around 2030.

How could science help improve teaching?
Conclusions of sleep studies could be incorporated into school activities, for example. Sleep is when memory is consolidated. Good quality sleep is essential for children to learn. In addition, wakefulness follows a cycle that varies from one individual to the next. I am part of the 20% of humanity that are morning people. I wake up spontaneously at 4 a.m. and I go to bed at 9 p.m. The other 80% tend to wake up and go to sleep later. The way schools are organized today, children have to get up at 5 a.m. to start class at 7 a.m. This doesn’t make sense from a physiological standpoint, since 80% of them are not at the peak of their cognitive capacity, due to their biological clocks.  Fernando Louzada of the Federal University of Paraná, a researcher associated with the Network, recommends that based on studies that he and other groups have conducted, the school day should begin and end a little later. Thus, the 20% of students who get up and arrive early would go play ball or do some other fun activity. This recommendation would only require a change in school management, based on scientific evidence. Afterwards, it would be necessary to conduct measurements to see if it really works.

Guga Melgar Scene from the play Um neurônio apaixonado, [A neuron in love], based on children’s books written by LentGuga Melgar

What has the Network already done?
We published four documents prepared by groups of specialists on topics that are relevant to education. One was on physiological factors that influence education; another focused on both students with disabilities and gifted students; a third dealt with socio-emotional competencies and metacognition; and the last was about teaching children to read and write. Each document contains suggestions for research (what we need to learn) and for public policies (what can be done based on this knowledge). With a postdoctoral fellowship paid by the Ayrton Senna Institute, researcher Daniele Botaro conducted a national census of researchers who have conducted studies associated with the science of learning. In collaboration with Jesus Mena Chalco, a professor of computer science at the Federal University of the ABC and author of an excellent data mining program, we conducted a survey of the 27,000 advisors registered with Capes who have significant scientific production in this area. We filtered it down to 300, whom we invited to join the Network, which today is composed of 90 leaders in research from various universities and states. Our goal is to reach 150 researchers this year. We have already brought together neurologists, computer scientists, economists, sociologists and educators. If many of them were to undertake work in research on education, we would achieve spectacular results. And of course, we must not forget the many research groups that already exist in Brazil and that have done respectable work in this area. We in the Network believe that these need to be articulated in chains of knowledge in order to gain momentum and scale.

What are the next steps?
This year we will hold a national meeting with scientists and educators from the education field, and then another one with scientists and entrepreneurs. The first was held in 2016, at the Museum of Tomorrow. We want to mobilize them to develop scientifically validated ideas and products for education. Today, there are several kits said to be capable of enhancing learning. Do they work? No one has measured them. We want to raise awareness in government to sponsor activities involving the science of learning, with the participation of state-run research foundations, to promote working together on the science of learning and stimulate interest in doing more applied work, as is done in health care. We submitted a plan to BNDES (Brazilian Development Bank) to create a National Center for the Science of Learning. This R$20 million project includes the construction of multi-user laboratories, open to researchers from academic institutions and companies.

In which phase of development should we invest more in education?
Early childhood – it is during this phase that the brain undergoes the most critical periods of transformation. This is when it is easiest to learn a second language and to move from an abstract concept of numerosity; for example, the ability to know which container holds more pieces of candy, to more concrete concepts, which enable us to quantify the number of pieces of candy in each container. It is easiest to learn up to the age of 20 or 30. From then on, a cognitive decline that has already been measured begins. The signs of aging do not begin at 60, they begin at 20!

At what phase of development is intervention to improve learning most efficient?
It depends on what is being taught. Teaching focused on development of socio-emotional abilities may be more effective in a pre-adolescent phase than earlier, because it is during adolescence that the prefrontal cortex, which is responsible for executive control of emotions and thoughts, becomes stabilized. Metacognition, which is the ability to reflect on how to learn better, is developed in adulthood. In other words, this is when we learn the habits associated with our own learning style. The development of this ability compensates for the loss of neuroplasticity that occurs as we age. Our ability to learn diminishes, but efficient use of the brain improves.

What attracted you to neuroscience?
I am the son of parasitologist Herman Lent (1911-2004) and of a chemist-pharmacist of Paraguayan origin, Maria Gregória Rivarola (1914-1995). My mother immigrated to Brazil, and because of the family structure of that time, when women did not work outside the home, she left chemistry behind, but she instilled a positive attitude in me in relation to science. When I was a child, my father would take me to the Oswaldo Cruz Institute in Manguinhos, and I would spend the day wandering around the laboratories. He was one of the 10 researchers at the Institute who were stripped of their political rights during the military regime, and he wrote the book O massacre de Manguinhos [The Massacre of Manguinhos] (1978, Avenir Editora). Because of my family background, I decided to follow a career in science when I was very young. Since there was little variation in this career path in Brazil in the 1960s, the alternative was to study medicine. I wanted to go into genetics, which was in fashion at that time. However, at the end of my first year, I became a physiology monitor for Eduardo Oswaldo Cruz (1933-2015), who was a specialist in the neurobiology of the visual system and the grandson of public health officer Oswaldo Cruz (1872-1917). I fell in love with neuroscience. I began by studying the visual system of skunks, which was the topic of the research being done by Cruz and by Carlos Eduardo Rocha Miranda (1934-2016). At that time, Rocha Miranda was in the United States. He was one of the people who discovered the so-called gnostic cells, from the visual cortex of monkeys, cells that respond only to complex stimuli. They are activated when a monkey sees photos of another monkey, but they do not respond to colors, contrasts or other simple stimuli. The discovery of these cells caused a huge stir in the field of psychology, since this indicated that there were specific neurons that identified the face of another member of the same species. I began research for my Master’s degree while I was still an undergraduate student, using a tracking technique for axon projections that Rocha Miranda had learned in the United States, and I became interested in neuroplasticity. I proposed an experiment to see what would happen with the extensions of the retina cells if an eye was surgically removed from one of the newborn skunks; it was an experimental model of congenital blindness. We used this strategy to study how this altered the animal’s visual system. This was the basis for my doctoral dissertation. I later did postdoctoral work at MIT (Massachusetts Institute of Technology), to study plasticity in hamsters. I worked with a true expert in this area, Gerald Schneider, who formulated a theory according to which we have two visual systems, one that controls movements and reflexes guided by vision, and the other, for complex visual perception. I spent three years in Boston. Two of my four children had already been born, and during this period, my daughter began to show signs of delay in mental development. I discovered that she had agenesis of the corpus callosum, a bundle of 200 million nerve fibers that connects the two hemispheres of the brain. This connection makes it possible for the right hand to interact with the left hand, and vice-versa, and for ideas processed in one hemisphere to reach the other. When I learned that my daughter Isabel had this problem, I became depressed. Schneider encouraged me: “You have to work on this.” I published three or four articles in the United States describing a model of a surgically caused disturbance in the development of the corpus callosum in a hamster.

What happens to those who do not have a corpus callosum?
In a study conducted with Fernanda Tovar-Moll, and published in 2014 in the journal PNAS, we discovered that people who are born without the corpus callosum, like my daughter, who is in her 30s and was analyzed in this study, present a compensatory mechanism for processing information and emotions. Since the corpus callosum of these people does not form while they are developing in the uterus, the neurons that create this structure seek other pathways and create alternative connections. We are now studying anomalous bundles, which may cause the limitations shown by these people. There is some degree of plasticity in the long-distance connections, but it is restricted to the synapses, the connections between neighboring cells. During formation of the corpus callosum, which occurs early, around the 12th week of gestation, alternative paths can appear.

What about your research on counting the number of cells in the brain?
That research is the result of the initial association with neuroscientist Suzana Herculano-Houzel, who developed a technique for counting brain cells. I became interested in this when I studied the human brain with the group from the brain bank at USP (University of São Paulo). My most cited work, which refers to the number of neurons in the human brain, was the result of this research; it was mentioned about 500 times by other studies. It was published in 2009 with one of my Master’s degree students, Frederico Azevedo.

It was in this study that you establish that the human brain has 86 billion neurons, which is fewer than the 100 billion that had previously been supposed.
Exactly. We continue working on this subject and now have a project underway with babies. We want to discover how many neurons humans are born with. This is a slower study, but it is very interesting. If babies are born with more neurons than adults have, this indicates that some were lost as the individual matures. If they are born with fewer neurons, then this indicates that there is a gain after birth. This could have many implications, including for the field of learning.

And what about your work with amputees?
That is also related to the corpus callosum. People who have any part of their body amputated, whether it be the arm, leg, breast, ear, etc. may present with a phenomenon called the phantom limb syndrome, which consists of feeling sensations in a body part that no longer exits. Amputation eliminates the part, but the region of the brain that represents this part continues to exist. The neurons remain alive, although they no longer receive information from that member. This seems to be activity by this area in the brain that is no longer in use. We have seen that the corpus callosum acquires a deficiency in the region where information used to be exchanged with the amputated body part. Our first article showing this came out in 2015 in the Journal of Neuroscience. It is the result of the doctoral studies by a neurosurgeon, Elington Lannes Simões. Our hypothesis is that it is this deficiency that creates the phantom sensation. The corpus callosum is a bundle of nerves that is mostly inhibitive. Activity by neurons in this bundle in one hemisphere modulates activity in the opposing hemisphere through inhibition. A deficiency in the corpus callosum can reduce this inhibition, producing the phantom sensation.

Why did you get into the area of educating the public about science?
I have a very dispersive brain. When my prefrontal cortex was little myelinated (immature), I was a member of the Brazilian Communist Party (PCB) and I was imprisoned for two months. I was from the academic center of the School of Medicine, and the military regime suspected that I was a communist. It was true, but I denied it until amnesty was announced. I was arrested on June 13, 1969 at my parents’ house, and they were roughed up during my arrest. I was kept at the marine barracks at Ilha das Flores until August 13. This experience gave me a social conscience that I took with me to my work in science and in spreading scientific knowledge.

And what did you do?
In 1976, I was the regional secretary of the Brazilian Society for the Advancement of Science (SBPC), in Rio. At that time, I began to talk to certain people, such as physicists Ennio Candotti and Alberto Passos Guimarães; anthropologists Gilberto and Otávio Velho, and others, and we began to think about founding a magazine to spread scientific knowledge. In 1979, I went to do my postdoctoral studies in the United States and Candotti worked on the project. He was the actual creator of the magazine Ciência Hoje. While I was at MIT, he asked me to visit magazines with scientific content, such as Discovery, to see how to create a magazine of this type in Brazil. The editor of Discovery laughed when I told him the plan. It was early 1982 and we wanted to launch the magazine in July, at the annual SBPC meeting in Campinas. We did not have a detailed plan, but we did manage to introduce the magazine on the date planned. Several colleagues of ours, professors, opposed this venture because they did not think it was necessary. After some resistance, the leadership of the SBPC agreed to publish Ciência Hoje, on the condition that it would not be an official vehicle of the entity. Now the SBPC has decided that the magazine will no longer be published, because of the serious financial situation of the magazine, which was already running a deficit, and the impact of the current crisis. The print version no longer exists, and even the on-line version will almost certainly end. The magazine Ciência Hoje das Crianças [Children’s Science Today] has been a more successful project. It was sold to the MEC, which distributed it in schools. For years, this strategy supported the Ciência Hoje Institute and its various products.

Why did you write books for children?
One of the activities at the annual SBPC meetings at the end of the 1980s was a visit by scientists to elementary schools. At one of them, I spoke to some 10-year old children about the brain and neurons.  To simplify the language, I used the term “nervous cells” instead of “neurons.” I spoke for 15 minutes and then a child asked: “Teacher, is there such a thing as a calm cell?” I then realized that my simplification had not worked and I began to think about how to write for children. This led to the five books in the series As aventuras de um neurônio lembrador, which was published by the company that my wife, Cilene Vieira, was founding at that time, Vieira & Lent. The series was transformed into a play, Um neurônio apaixonado [A neuron in love], by scriptwriter Claudia Valli.

You recently made public statements about some scientific issues, which is not very common among scientists. Why?
I cannot remain silent when I believe I should speak, as I did when Suzana Herculano-Houzel moved to the United States (in May 2016, Lent posted a message on Facebook addressed to Herculano-Houzel that said “…Your words speak of dejection, of giving up on and abandoning Brazil and our science. This is surrendering…We cannot tell our students to give up, to abandon everything”). I also disagreed with the statements made by fellow neuroscientist Miguel Nicolelis in 2007. When Nicolelis came back to work in Brazil he said, on the site of the Alberto Santos Dumont Association for Research Support, which he created, something about the research center that he was building in Natal (Rio Grande do Norte): “Here is where Brazilian neuroscience is being born.” That was not true. Neuroscience was already being done in Brazil, by people such as Aristides Leão (1914-1993) and Carlos Chagas Filho (1910-2000) in Rio, Miguel Covian (1913-1992) in Ribeirão Preto, César Timo-Iaria (1925-2005), who was his professor at USP, and Iván Izquierdo, in Rio Grande do Sul. Nicolelis was messianic, suggesting that a single researcher could solve all the problems in this area. We had already seen this same thing happen with Edson Xavier de Albuquerque, head of the Pharmacology Department at the University of Maryland, in the United States. He was a friend of João Leitão de Abreu (1913-1992), who had been a Minister in one of the military governments and joined UFRJ with the idea of solving the problem of Brazilian pharmacology. There was nothing left over afterwards. He went away and did not leave anyone behind to follow in his footsteps.