An award is made to Indiana University, Bloomington, to acquire a 512 micro-electrode array instrument (512MEA) for recording and stimulating electrical activity in samples of brain tissue. The 512MEA can be used to measure how groups of several hundred neurons send information back and forth to each other. The ability to map information transfer in networks of this size is expected to be very valuable. Many theories predict that information transfer will change in networks of hundreds of neurons after learning, after exposure to drugs of addiction or toxins, after seizures and after traumatic injury. Other theories predict that brain networks process information in a nearly optimal way, an idea that has remained largely untested. Use of the 512MEA is therefore expected to provide new knowledge relevant to understanding how learning occurs, how drug addiction begins, how poisons affect brain health, how epileptic seizures start, how the brain responds to injury, and how the brain optimizes information processing. Ultimately, this work could benefit society by helping to improve teaching and learning in schools, by helping in the treatment of epilepsy patients, people exposed to harmful substances, war veterans, and by suggesting new ways to design brain-like computers. To maximize the number of students and laboratories using this device, it will be rotated between the Department of Physics, the Department of Brain and Psychological Sciences, and the Medical School.
The research and training opportunities that are opened by the 512MEA center on two topics of investigation: (1) emergent properties, and (2) information transfer. Emergent Properties: Many basic emergent properties of the brain like pattern recognition, associative memory, formation of cell assemblies, neuronal avalanches, synchronized pulses, and collective computations are predicted to arise first in populations of hundreds of interconnected neurons. Although most of these phenomena have been predicted for decades, they have remained largely unexplored for lack of proper instrumentation. The 512MEA would allow all of these topics to be researched in detail, many for the first time. Information transfer: It is almost completely unknown how information transfer differs in networks from naive animals and those that have learned; between networks exposed to neuro-active substances and those that have not; between developing networks and those that have matured. Because the 512MEA can record neural activity at millisecond resolution, it can identify which brain cell became active first in a chain of activity. This ability is crucial, as it will indicate the direction of influence between neurons. Optical methods of recording activity between hundreds of neurons often do not have this capability. The 512MEA can thus permit many of these topics to be researched for the first time.
