Attractors and Criticality in Cortical Slice Cultures

Indiana University, Bloomington IN

Investigators

Abstract

The physical sciences have had great success in describing how complex phenomena can emerge from the collective interactions of many similar units. Waves, synchrony, phase transitions, and self-organization are all examples of this. Although the brain is tremendously complex, it is composed of many units, neurons, which appear to be similar. This resemblance has led many researchers to borrow concepts from physics in an effort to explain neural function. Simulations indicate that stable states can be used to store information, and that the critical point maximizes both information transmission and information storage. While this body of theory has prospered, experiments to test it have been few. New advances in technology have allowed thousands of interconnected neurons to be grown in culture on microfabricated arrays of many electrodes. These cultured brain slices can be kept alive for weeks while their spontaneous electrical activity is recorded. The large data sets produced by these experiments allow many of the hypotheses inspired by statistical physics to be examined in real neural tissue. A series of experiments to test hypotheses about stable states and the critical point are proposed to advance this research. The data from these experiments will be used to construct complementary network simulations that should to lead to further testable predictions. Knowledge gained from these experiments is expected to advance the understanding of computational principles used by networks of living neurons and to be useful in designing synthetic devices that exploit these principles. These studies are expected to have broader impact in two areas. First, analysis tools developed for these culture experiments are expected to be applicable to data from whole behaving animals as well. Second, this research will contribute to training interdisciplinary scientists who are expected to be valuable in interpreting the deluge of neural data that will certainly come as recording technology and computer capacity continue to improve.