Experimental Studies of Chaotic Neural Behavior: Cellular Activity and Electroencephalographic Signals

  • P. E. Rapp
  • I. D. Zimmerman
  • A. M. Albano
  • G. C. deGuzman
  • N. N. Greenbaun
  • T. R. Bashore
Part of the Lecture Notes in Biomathematics book series (LNBM, volume 66)

Abstract

Deterministic systems can display a form of highly irregular, quasirandom behavior called chaos. Even though the observed behavior is very complex, the systems which generate it can be very simple. Thus, in at least some instances, irregular biological systems may obey a simple, potentially discoverable, deterministic dynamical law. These systems can undergo reversible transitions to and from chaotic dynamics in response to small changes in parameter values. As a long term goal, this form of analysis may suggest more effective responses to disordered behavior in physiological control systems.

This contribution is concerned with chaos in neural systems and its possible role in epileptogenesis. Calculation of information dimension provides a procedure for distinguishing between chaotic and random behavior. This technique is applied to experimental data from two preparations: spontaneous activity of cortical neurons in the pre- and post-central gyri of the squirrel monkey and human electroen-cephalographic signals. In each case the results suggest that these systems can display low dimensional chaotic behavior.

Keywords

Entropy Convection Manifold Dopamine Schizophrenia 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • P. E. Rapp
    • 1
  • I. D. Zimmerman
    • 1
  • A. M. Albano
    • 2
  • G. C. deGuzman
    • 2
  • N. N. Greenbaun
    • 3
  • T. R. Bashore
    • 4
  1. 1.Department of Physiology and BiochemistryThe Medical College of PennsylvaniaPhiladelphiaUSA
  2. 2.Department of PhysicsBryn Mawr CollegeBryn MawrUSA
  3. 3.Department of Mathematical SciencesTrenton State CollegeTrentonUSA
  4. 4.Department of Psychiatry, The Medical College of PennsylvaniaThe Eastern Pennsylvania Psychiatric InstitutePhiladelphiaUSA

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