Summary

Proceedings of the 2012 International Symposium on Nonlinear Theory and its Applications

2012

Session Number:B1L-B

Session:

Number:312

Multi-Scale Causation in Brain Dynamics

Hans Liljenström,  

pp.312-315

Publication Date:

Online ISSN:2188-5079

DOI:10.15248/proc.1.312

PDF download (301KB)

For any complex system, consisting of several organizational levels, the problem of causation is profound. Usually, science considers upward causation as fundamental, paying less or no attention to any downward causation. This is also true for the nervous system, where cortical neurodynamics, or even higher mental functions of the brain are normally considered causally dependent on the nerve cell activity, or even the activity at the ion channel level. This study presents both upward and downward causation in cortical neural systems, using computational methods with focus on cortical fluctuations. We have developed models of paleo-and neocortical structures, in order to study their mesoscopic neurodynamics, as a link between the microscopic neuronal and macroscopic mental events and processes. We demonstrate how both noise and chaos may play a role for the functions of cortical structures. While microscopic random noise may trigger meso-or macroscopic states, the nonlinear dynamics at these levels may also affect the activity at the microscopic level.

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