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Extreme stability and almost periodicity in continuous and discrete neuronal models with finite delays

Published online by Cambridge University Press:  17 February 2009

S. Mohamad
Affiliation:
On leave from Department of Mathematics, University Brunei Darussalam, Bandar Serf Begawan BE, 1410, Brunei Darussalam; e-mail: [email protected].
K. Gopalsamy
Affiliation:
Mathematics and Statistics, School of Informatics and Engineering, Flinders University of South Australia, Bedford Park SA 5042, Australia; e-mail: [email protected].
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Abstract

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We consider the dynamical characteristics of a continuous-time isolated Hopfield-type neuron subjected to an almost periodic external stimulus. The model neuron is assumed to be dissipative having finite time delays in the process of encoding the external input stimulus and recalling the encoded pattern associated with the external stimulus. By using non-autonomous Halanay-type inequalities we obtain sufficient conditions for the hetero-associative stable encoding of temporally non-uniform stimuli. A brief study of a discrete-time model derived from the continuous-time system is given. It is shown that the discrete-time model preserves the stability conditions of the continuous-time system.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 2002

References

[1]Baker, C. T. H. and Tang, A., “Generalised Halanay inequalities for Volterra functional differential equations and discretised versions”, Report 299, Manchester Centre for Computational Mathematics, The University of Manchester, England, 1996.Google Scholar
[2]Besicovitch, A. S., Almost Periodic Functions (Dover, New York, 1954).Google Scholar
[3]Bondarenko, V. E., “Self-organization processes in chaotic neural networks under external periodic force”, Int. J. Bifur. Chaos 7 (1997) 18871895.CrossRefGoogle Scholar
[4]Broomhead, D. S. and Iserles, A. (eds.), The dynamics of numerics and the numerics of dynamics (Clarendon Press, Oxford, 1992).Google Scholar
[5]Caianiello, E. R. and de Luca, , “Decision equation for binary systems; application to neuronal behaviour”, Kybemetik 3 (1966) 3340.Google Scholar
[6]Chapeau-Blondeau, F. and Chauvet, G., “Stable, oscillatory and chaotic regimes in the dynamics of small neural networks with delay”. Neural Networks 5 (1992) 735744.CrossRefGoogle Scholar
[7]Corduneanu, C., Almost Periodic Functions (Interscience, New York, 1968).Google Scholar
[8]Eckhorn, R., Bauer, R., Jordan, W., Kruse, W., Munk, M. and Rertboeck, H. J., “Coherent oscillations: A mechanism for feature linking in the visual cortex”, Biol. Cybern. 60 (1988) 121130.CrossRefGoogle ScholarPubMed
[9]Engel, A. K., Kreiter, A. K., Konig, P. and Singer, W., “Synchronization of oscillatory neural responses between striate and extrastriate visual cortical areas of the cat”, Proc. Natl. Acad. Sci. 88 (1991) 60486052.CrossRefGoogle Scholar
[10]Fink, A. M., Almost Periodic Differential Equations (Springer, New York, 1974).CrossRefGoogle Scholar
[11]Freeman, W. J., “The physiology of perception”, Sci. Amer. 02 (1991).Google Scholar
[12]Freeman, W. J., Yau, Y. and Burke, B., “Central pattern generating and recognizing in olfactory bulb: A correlation learning rule”, Neural Networks 1 (1988) 277288.CrossRefGoogle Scholar
[13]Gopalsamy, K., Stability and Oscillations in Delay Differential Equations of Population Dynamics (Kluwer Academic Publishers, The Netherlands, 1992).CrossRefGoogle Scholar
[14]Gopalsamy, K. and He, X. Z., “Delay-independent stability in bidirectional associative memory networks”, IEEE Trans. Neural Networks 5 (1994) 9981002.CrossRefGoogle ScholarPubMed
[15]Gopalsamy, K. and He, X. Z., “Stability in asymmetric Hopfield nets with transmission delays”, Physica D 76 (1994) 344358.CrossRefGoogle Scholar
[16]Gopalsamy, K. and He, X. Z., “Dynamics of an almost periodic logistic integrodifferential equation”, Methods Appl. Anal. 2 (1995) 3866.CrossRefGoogle Scholar
[17]Gopalsamy, K., He, X. Z. and Wen, L., “Global attractivity and oscillations in an almost periodic delay logistic equation”, Nonlinear Times Digest 1 (1994) 924.Google Scholar
[18]Gray, C. M., König, P., Engel, A. K. and Singer, W., “Oscillatory responses in cat visual cortex exhibit intercolumnar synchronization which reflects global stimulus properties”, Nature 388 (1989) 334337.CrossRefGoogle Scholar
[19]Halanay, A., Differential Equations (Academic Press, New York, 1966).Google Scholar
[20]Hjelmfelt, A. and Ross, J., “Pattern recognition, chaos and multiplicity in neural networks and excitable systems”, Proc. Nat. Academy Sci. 91 (1994) 6367.CrossRefGoogle ScholarPubMed
[21]Istratescu, V. I., Fixed Point Theory (D. Riedel Publ. Co., Dordrecht, 1981).CrossRefGoogle Scholar
[22]König, P. and Schillen, J. B., “Stimulus-dependent assembly formation of oscillatory responses: I. Synchronization”, Neural Comput. 3 (1991) 155166.CrossRefGoogle ScholarPubMed
[23]LaSalle, L. P. and Lefschetz, S., Stability by Lyapunov's Direct Method with Applications (Academic Press, New York, 1961).Google Scholar
[24]Mickens, R. E., Nonstandard Finite Difference Models of Differential Equations (World Scientific, River Edge, NJ, 1994).Google Scholar
[25]Moreira, J. E. and Auto, D. M., “Intermittency in a neural network with variable threshold”, Europhys. Lett. 21 (1993) 639.CrossRefGoogle Scholar
[26]Ott, E., Grebogi, C. and Yorke, J. A., “Controlling chaos”, Phys. Rev. Lett. 64 (1990) 11961199.CrossRefGoogle ScholarPubMed
[27]Rescigno, A., Stein, R. B., Stein, R. L. and Poppele, R. E., “A neuronal model for the discharge patterns produced by cyclic inputs”, Bull. Math. Biophys. 32 (1970) 337353.CrossRefGoogle ScholarPubMed
[28]Skarda, C. A. and Freeman, W. J., “How brains make chaos in order to make sense of the world”, Brain Behavioural Sci. 10 (1987) 161195.CrossRefGoogle Scholar
[29]Stuart, A. M. and Humphries, A. R., Dynamical systems and numerical analysis (Cambridge University Press, Cambridge, 1996).Google Scholar
[30]Wang, X. and Blum, E. K., “Discrete-time versus continuous-time models of neural networks”, J. Comput. Syst. Sci. 45 (1992) 119.CrossRefGoogle Scholar
[31]Yau, Y., Freeman, W. J., Burke, B. and Yang, Q., “Pattern recognition by a distributed neural network: An industrial application”. Neural Networks 4 (1991) 103121.CrossRefGoogle Scholar
[32]Yoshizawa, T., “Extreme stability and almost periodic solutions of functional-differential equations”. Arch. Rat. Mech. Anal. 17 (1964) 148170.CrossRefGoogle Scholar
[33]Yoshizawa, T., Stability Theory and the Existence of Periodic Solutions and Almost Periodic Solutions (Springer, New York, 1975).CrossRefGoogle Scholar