ABSTRACT Astrocytes, the dominant glial cell type, modulate synaptic information transmission. Each astrocyte is organized in non-overlapping domains. Here, a formally based model of the possible significance of astrocyte domain organization is proposed. It is hypothesized that each astrocyte contacting n neurons with m synapses via its processes generates dynamic domains of synaptic interactions based on qualitative criteria so that it exerts a structuring of neuronal information processing. The formalism (morpho-grammatics) describes the combinatorics of the various astrocytic receptor types for occupancy with cognate neurotransmitters. Astrocytic processes are able both to contact synapses and retract from them. Rhythmic oscillations of the astrocyte may program the domain organization, where clock genes may play a role in rhythm generation. For the interpretation of a domain organization a player of a string instrument is used as a paradigm. Since astrocytes form networks (syncytia), the interactions between astrocyte domains may be comparable to the improvisations in a jazz ensemble. Given the fact of a high combinational complexity of an astrocyte domain organization, which is formally demonstrable, and an uncomputable complexity of a network of astrocyte domains, the model proposed may not be testable in biological brains, but robotics could be a real alternative.
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nullMitterauer, B. (2010) Significance of the astrocyte domain organization for qualitative information structuring in the brain. Advances in Bioscience and Biotechnology, 1, 391-397. doi: 10.4236/abb.2010.15052.
 Volterra, A. and Meldolesi, J. (2005) Astrocytes, from brain glue to communication elements: The revolution continues. Nature Reviews Neuroscience, 6, 626-640.
Auld, D.S. and Robitaille, R. (2003) Glial cells and neurotransmission: An inclusive view of synaptic function. Neuron, 40, 389-400.
Halassa, M.M. and Haydon, P.G. (2010) Integrated brain circuits: Astrocytic networks modulate neuronal activity and behaviour. Annual Review of Physiology, 72, 335-355.
Haydon, P.G. (2001) Glia: Listening and talking to the synapse. Nature Reviews Neuroscience, 2, 185-193.
Haydon, P.G. and Carmignoto, G. (2006) Astrocyte control of synaptic transmission and neurovascular coupling. Physiological Review, 86, 1009-1031.
Verkhratsky, A.and Butt, A. (2007) Glial neurobiology. Wiley, West Sussex.
Nedergaard, M., Ransom, B. and Goldman, S.A. (2003) New roles for astrocytes: Redefining the functional architecture of the brain. Trends in Neuroscience, 25, 523-530.
Halassa, M.M., Fellin, T., Takano, H., Dong, J. and Haydon, P.G. (2007) Synaptic islands defined by the territory of a single astrocyte. The Journal of Neuroscience, 27, 6473-6477.
Santello, M. and Volterra, A. (2010) Astrocytes as aide-mémoires. Nature, 463, 169-170.
Oberheim, N.A., Wang, X., Goldman, S. and Nedergaard, M. (2006) Astrocytic complexity distinguishes the human brain. Trends in Neuroscience, 29, 547-553.
Kettenmann, H. and Steinh?user, C. (2005) Receptors for neurotransmitters and hormones. In: Kettenmann, H. and Ransom, B.R., Eds., Neuroglia, Oxford University Press, Oxford, 131-145.
McCarthy, K.D. and Salm, A.K. (1991) Pharmacologically-distinct subsets of astroglia can be identified by their calcium response to neuroligands. Neuroscience, 2-3, 325-333.
Guenther, G. (1962) Cybernetic ontology and transjunctional operations. In: Yovits, M.C., Jacobi, G.T. and Goldstein, G.D., Eds., Self-organizing Systems, Spartan Books, Washington DC, 313-392.
Guenther, G. (1976) Beitr?ge zur Grundlegung einer operations f?higen Dialektik. Band I, Meiner, Hamburg.
Thomas, G.G. (1985) Introduction to kenogrammatics. Proceedings of the 13th Winter School on Abstract Analysis, section of Topology, Rendiconti del Circolo Matematico di Palermo, Supplemento No. 11, serie II, 113-123.
Hirrlinger, J., Hulsmann, S. and Kirchhoff, F. (2004) Astroglial processes show spontaneous motility at active synaptic terminals in situ. European Journal of Neuroscience, 20, 2235-2239.
Haber, M., Zhou, L. and Murai, K.K. (2006) Cooperative astrocyte and dendritic spine dynamics at hippocampal excitatory synapses. Journal of Neuroscience, 26, 8887-8891.
Cooper, M.S. (1995) Intercellular signalling in neuronal-glial networks. BioSystems, 34, 65-85.
Newman, E.A. and Zahs, K.R. (1997) Calcium waves in retinal glial cells. Science, 275, 844-846.
Mitterauer, B., Garvin, A.M. and Dirnhofer, R. (2000) The sudden infant death syndrome: A neuro-molecular hypothesis. Neuroscientist, 6, 154-158.
Parri, H.R., Gould, T.M. and Crunelli, V. (2001) Spontaneous astrocytic Ca2+ oscillations in situ drive NMDAR-mediated neuronal excitation. Nature Neuroscience, 4, 803-812.
Winship, I.R., Plaa, N. and Murphy, T.H. (2007) Rapid astrocyte calcium signals correlate with neuronal activity and onset of the hemodynamic response in vivo. Journal of Neuroscience, 27, 6268-6272.
Barnes, S.J. and Finnerty, G.T. (2010) Sensory experience and cortical rewiring. Neuroscientist, 16, 186-198.
Mitterauer, B. (2001) Clocked perception system. Journal of Intelligent Systems, 11, 269-298.
Mitterauer, B. and Kopp, C. (2003) The self-composing brain: Towards a glial-neuronal brain theory. Brain and Cognition, 51, 357-367.
Iwasaki, K. and Thomas, J.H. (1997) Genetics in rhythm. Trends in genetics, 13, 111-115.
Lloyd, D. (1998) Circadian and ultradian clock-controlled rhythms in unicellular microorganisms. Advances in Microbiological Physiology, 39, 291-338.
Reick, M., Garcia, J.A., Dudley, C. and McKnight, S.L. (2001) NPAS 2: An analog of clock operative in the mammalian forebrain. Science, 293, 506-509.
Schibler, U., Ripperger, J.A. and Brown, S.A. (2001) Chronobiology-reducing time. Science, 293, 437-438.
McCulloch, W.S. (1965) Embodiments of mind. The MIT Press, Cambridge.
Helfrich-F?rster, C. (1995) The period clock gene is expressed in the central nervous system neurons which also produce a neuropeptide that reveals the projections of circadian pacemaker cells within the brain of Drosophila melanogaster. Proceedings of the National Academy of Sciences of USA, 92, pp. 612-616.
Flight, M.H. (2007) Circadian rhythms: glia set the beat. Nature Reviews Neuroscience, 8, 654.
Mitterauer, B. (2004) Computer System, particularly for simulation of human perception via sense organs. United States Patent, 6, 697, 789B2.
Mitterauer, B. (2007) Where and how could intentional programs be generated in the brain? A hypothetical model based on glial-neuronal interactions. BioSystems, 88, 101-112.
Nadkarni, S., Jung, P. and Levine, H. (2008) Astrocyte optimize the synaptic transmission of information. PloS Computational Biology, 4, 1-11.