Scientists Reconstruct Rat Brain on Computer

Eighty-two researchers from around the world reconstructed a section of a rat brain on a computer.

The Blue Brain Project employed scientists and engineers at the Ecole Polytechnique Federale de Lausanne (EPFL)and other institutions in Israel, Spain, Hungary, USA, China, Sweden, and the UK to create a first draft computer reconstruction of a piece of a rat neocortex. The Blue Brain Project is partly supported by the Human Brain Project, a 10-year European research program costing over $1 billion.

The reconstruction is comprised of one-third of a cubic millimeter of brain tissue holding roughly 30,000 neurons connected by almost 40 million synapses. Henry Markram of EPFL, who heads both the blue Brain Project and the Human Brain project, admitted that to use the data from the small section of the brain that has been reconstructed to assume a reconstruction of the entire human brain, with its 85 million neurons, would be problematic. Cori Nargmann, co-director of the Kavli Neural Systems Institute at Rockefeller University, agreed, telling The New York Times, the “simulations are in their infancy,” and adding, “They built a 747, and it’s taxiing around the runway. I haven’t seen it fly yet, but it’s promising.”

The researchers extrapolated from data they found in some cells to posit how the whole would respond, then simulated certain kinds of brain activity and noted that the reconstruction and living tissue acted in similar fashion. In one such simulation, they analyzed how different types of neuron respond when the fibers coming into the neocortex were stimulated by incoming fibers, and discovered that the responses of the neurons in the digital reconstruction were akin to those observed in the laboratory.

In July 2014, hundreds of neuroscientists from around the world sent a open letter condemning the project, arguing that the cost of the project, estimated at roughly $130 million a year over the next 10 years, could set back Europe’s scientific progress. Zachary Mainen, a neuroscientist at the Champalimaud Center for the Unknown, in Lisbon, said, “We can’t simulate the 302 neurons in a nematode brain. It’s a bit premature to simulate the 100 billion neurons in a human brain.” The letter also slammed the dissolution of the project’s Cognitive Architectures branch; Mainen said, “It’s the departure of the entire cognitive neuroscience aspect of the H.B.P. It’s not clear why they would throw that out.”