Researchers were able to identify architectural patterns that arise when the brain had to comprehend information before disintegrating into nothing by utilizing a sophisticated mathematical method.
The discovery showed that the brain is full of multi-dimensional geometrical structures operating in as many as 11 dimensions.
A team of researchers from the Blue Brain Project, a Swiss research effort dedicated to constructing a supercomputer-powered recreation of the human brain, created this brain model.
The team employed algebraic topology, a field of mathematics used to explain the characteristics of objects and spaces independent of their form change. This is the first time this branch of math has been applied to neuroscience.
“Algebraic topology is like a telescope and microscope at the same time. It can zoom into networks to find hidden structures—the trees in the forest—and see the empty spaces—the clearings—all at the same time,” said study author Kathryn Hess.
In the study, researchers ran a series of experiments on virtual brain tissue to identify brain structures that would never emerge by chance. They then repeated the trials on actual brain tissue to validate their virtual findings. They observed that when they stimulated the virtual tissue, clusters of neurons formed a clique. To generate a precise geometric object, each neuron links to every other neuron in a very particular way. The greater the dimensions, the more neurons in a clique.
“We found a world that we had never imagined,” said lead resercher, neuroscientist Henry Markram from the EPFL institute in Switzerland. “There are tens of millions of these objects even in a small speck of the brain, up through seven dimensions. In some networks, we even found structures with up to 11 dimensions.”
“The appearance of high-dimensional cavities when the brain is processing information means that the neurons in the network react to stimuli in an extremely organized manner,” said one of the researchers, Ran Levi.
“It is as if the brain reacts to a stimulus by building then razing a tower of multi-dimensional blocks, starting with rods (1D), then planks (2D), then cubes (3D), and then more complex geometries with 4D, 5D, etc. The progression of activity through the brain resembles a multi-dimensional sandcastle that materializes out of the sand and then disintegrates,” he said.
These findings offer a tantalizing new picture of how the brain processes information, but the researchers point out that it is still unclear what causes the cliques and holes to develop in such particular ways. More research will be required to discover how the intricacy of these multidimensional geometric patterns generated by our neurons corresponds with the difficulty of different cognitive activities.
Cliques of Neurons Bound into Cavities Provide a Missing Link between Structure and Function, Michael W. Reimann, Max Nolte, Martina Scolamiero, Katharine Turner, Rodrigo Perin, Giuseppe Chindemi, Paweł Dłotko, Ran Levi, Kathryn Hess and Henry Markram
Published: June 2017
DOI: https://doi.org/10.3389/fncom.2017.00048