Hebrew University’s Interdisciplinary Center for Neural Computation – a ‘center of excellence’ that scientists around the world are turning towards.Without the math and computation skills involved in analyzing brain signals, researchers at the Hebrew University might have done no more than study monkey minds. Instead that primate research is leading to the development of a robotic arm that can respond to the brain commands of a paralyzed person.
The eclectically trained scientists at the Hebrew University of Jerusalem’s Interdisciplinary Center for Neural Computation are used to conducting multidisciplinary work such as this. The center is one of the first programs in the world to conduct research, and train others to do so, by combining fields such as biology, physics, math, psychology, engineering and philosophy in an attempt to understand one of the most complex machines never invented: the human brain.
The neural computation center’s most recent major accomplishment, however, is not directly linked to any particular discovery, but to a European gold ribbon. Earlier this year, the European Union selected the interdisciplinary program as a “center of excellence” whose “combination of facilities, equipment and expertise at one site appears to be genuinely rare in Europe.”
“We are very proud that the EU has decided to grant us this important and rare designation,” said Prof. Idan Segev, the center’s director. “We are trying to build a researcher who is no longer a ‘classic researcher’ studying only a single discipline,” he told ISRAEL21c. “Otherwise we simply won’t understand the brain.”
As an outcome of the citation of excellence, the Hebrew University center has signed an agreement with the EU to host some 100 researchers from Europe to train them in applying a multi-disciplinary approach to understanding the functions of the brain. Seventeen countries, including England, France, Portugal, Greece and the Scandinavian states, have already expressed an interest in sending scientists to the center to learn more about its methods, said Segev, a professor of neurobiology at Hebrew University who co-founded the neural computation center in 1990.
The center also has close ties with an American doctorate program at the California Institute of Technology called Computation and Neural Systems, or CNS, and the two run a joint student exchange program. Although the sister centers share a similar approach to studying the brain, two features that distinguish the Hebrew University center from its Caltech counterpart are the size of its master’s-doctorate program and its emphasis on theory.
CNS, which started its doctorate program in 1986, has about 25 percent fewer students listed than the Hebrew University center, which has a total of about 60 students in its program every year.
The Israeli center also concentrates more on theory than experimentation, which requires far greater material resources, said Roni Jortner, a PhD student at the Hebrew University center who recently returned from about three years at CNS. Jortner, 33, spent his time in California conducting experiments on insects’ brains to study the part of the brain that deals with the sense of smell. Back in Israel, he plans to use his experimental results to develop theoretical models of the scent system and simulations of brain activity.
The European scientists, meanwhile, haven’t been waiting around for the EU’s official certification. Hermann Cuntz, a 30-year-old post-doctoral researcher from Munich, has been working at the Israeli center since last February, where he has been researching the way in which the shape of nerve cells affects their function.
Cuntz is using computing skills to build theoretical models that predict rules for the way in which the branching dendrite structures, which conduct impulses toward the body of a nerve cell, develop. He is also applying his biology background to conducting experiments on real neurons and determine which components of the prediction are right.
“In principle the brain has always been a system which was approached by all types of different methods – psychophysics and electrophysiology, biology and molecular [biology], psychology, even philosophy, and all these come together,” said Cuntz. “It’s not possible – to understand the brain from the point of just one of those perspectives – you have to put everything together.”
Cuntz appreciates being in a program in which scientists are knowledgeable about practical experimentation as well as theoretical modeling.
“Often, when there are only theoreticians, the models are based on too simple, not realistic assumptions. With biologists, there is no model at all to put the experimental results in context,” he said. “Here, everybody has the basis to understand the theoretical work as well, and that’s very impressive.”
In addition to describing the neural computation center’s multidisciplinary approach, the EU citation also praises it for researching “topics of major importance to human health and development,” such as Parkinson’s disease.
Prof. Hagai Bergman, a Hebrew University physiologist and a faculty member at the center, has discovered that the Parkinson’s tremor is caused by abnormal electrical activity in a small group of cells in the deep brain.
Rather than merely recording the abnormality, scientists at the center decided to work on changing the increased frequency of oscillation. The practice, known as deep brain stimulation, is now conventional treatment in many hospitals for Parkinson’s disease, Segev said, adding that Bergman recently participated in such an operation at Hadassah University Hospital.
Research on the use of robotics to ease paralysis, meanwhile, is nothing if not multidisciplinary. Researchers at the center have developed fast algorithms to extract the code underlying the signals emitted by the neurons in monkeys’ brains when they want to move parts of their bodies (their arms, for instance), said Segev.
By analyzing the code and separating the signals for each cell, the researchers help enable the use of a robotic arm that a paralyzed person can use to respond to the commands the brain gives to move the arm, but which a paralyzed arm cannot physically carry out – a process Segev said is in an advanced stage of development.
“It’s really not science fiction anymore,’ said Segev, who discussed the paralysis treatment research with Christopher Reeve, the late Superman actor who was paralyzed in an accident, during Reeve’s visit to Israel in 2003.
But the specific research underway at the center should not obscure what Segev considers the ultimate goal of neural computation: constructing a mathematical theory of the brain. “Without this, we won’t be able to say that we have understood this machine,” he said.
If scientists manage to understand the principles behind the way the brain functions and create a mathematical theory, they could also – theoretically, at least – fix parts of the brain based on the model rather than through trial and error, and potentially even transplant parts of the brain that are missing or damaged, said Segev.
Despite the recognition accorded the center and its scientists, something is still lacking, he said.
“We’re missing the big principle,” said Segev. “This is the task of the 21st century.”