P.M. Balaban – Corresponding member оf RAS, Dr.Sc. (Biol.), Professor, Director, FGBUN «Institute of Higher Nervous Activity and Neurophysiology RAS» (Moscow)
Typically, when describing the work of a brain and the formulation of principles of neural network functioning, the neurons inte-raction is described as achievement of the trigger threshold in neurons as a result of the activity of network elements, and the transmission and coding of information are attributed implicitly to nerve impulses arising under the law of "all-or-nothing".
The aim of this short review is to demonstrate and single out some most important principles of interactions in the brain that usually are ignored during construction of the models of nervous system, neural network modeling. First, interaction between neurons is not digital, it is analogous, because only inside one neuron information is transmitted using electrical events, while majority of synapses is chemical, what means that it depends on quantity of released transmitter, effectivity and quantity of receptors in postsynaptic neurons, and implicitly suggests a possibility of influence the neighbors at a time scale that significantly exceeds the impulse conduction time. In fact, in the nervous system the neuromodulation, which implies changes of future responses due to present activity, is one of the most important ways of neural interactions. The neuromodulation principle of neural net activity always is used for achievement of homeostatic state of the nervous system that is necessary for survival. Any system that do not have such homeostatic activity will “run away” very soon after several external inputs, what never happens with the brain – it is always ready to percept new stimuli. One of the mechanisms of such homeostatic plasticity is negative feedback mediated by endocannabinoids. The decision making is another point raised in the present paper. The decision “to spike or not to spike” is made by each neuron in the network, but the overall decision of the network is mediated by a specialized individual neurons (in invertebrates), and by a class of neurons in vertebrates. The “decision neurons” have to be involved in the behavioral act that is triggered, have to be necessary for its triggering, sufficient for its triggering, and to receive polymodal sensory information which potentially can trigger a particular behavior. Major changes due to the learning procedure happen in the synaptic inputs of such decision neurons and simultaneously in the synaptic inputs of modulatory neurons specific for given behavior.
- Chistopol'skij I.A., Saharov D.A. Nesinapticheskaja integracija tel nervnyh kletok v CNS ulitki // Rossijskij fiziologicheskij zhurnal im. I.M. Sechenova. 2001. T. 87. № 11. S. 1540–1547.
- Saharov D.A. Genealogija nejronov. M.: Nauka. 1974.
- Holmes C.J., Mainville L.S., Jones B.E. Distribution of cholinergic, GABAergic and serotonergic neurons in the medial medullary reticular formation and their projections studied by cytotoxic lesions in the cat // Neuroscience. 1994. V. 62. Oct. № 4. P. 1155–1178.
- Ovsepian S.V. The birth of the synapse // Brain Struct Funct. 2017. Jun. 13. doi: 10.1007/s00429-017-1459-2.
- Nikitin E.S., Balaban P.M., Kemenes G. Nonsynaptic plasticity underlies a compartmentalized increase in synaptic efficacy after classical conditioning // Curr. Biol. 2013. V. 23. № 7. P. 614–619.
- Jekkls Dzh. Fiziologija sinapsov. M.: Mir. 1966.
- Dannenberg H., Hinman J.R., Hasselmo M.E. Potential roles of cholinergic modulation in the neural coding of location and movement speed // J. Physiol Paris. 2016. V. 110. №1-2. P. 52–64.
- Balaban P.M., Zaharov I.S. Obuchenie i razvitie: obshhaja osnova dvuh javlenij. M.: Nauka. 1992. 150 s.
- Balaban P.M. Cellular mechanisms of behavioral plasticity in terrestrial snail // Neurosci Biobehav Rev. 2002. V. 26. №5. P. 597–630.
- Bullock T.H. The problem of recognition in an analyser made of neurons // In: Sensory Communications / Ed. W.A. Rosen-blith. Cambridge, MIT Press, 1961. P. 714–721.
- Daghfous G., Green W.W., Alford S.T., Zielinski B.S., Dubuc R. Sensory Activation of Command Cells for Locomotion and Modulatory Mechanisms: Lessons from Lampreys // Front Neural Circuits. 2016. Mar. 22. № 10. P. 18.
- Tervo D.G.R., Proskurin M., Manakov M., Kabra M., Vollmer A., Branson K., Karpova A.Y. Behavioral variability through stochastic choice and its gating by anterior cingulate cortex // Cell. 2014. Sep. 25. V. 159. № 1. P. 21–32.
- Zakharov I.S., Ierusalimsky V.N., Balaban P.M. Pedal serotonergic neurons modulate the synaptic input of withdrawal interneurons in Helix // Invertebrate Neuroscience. 1995. V. 1. №1. P. 41–52.
- Meunier CN, Chameau P, Fossier PM. Modulation of Synaptic Plasticity in the Cortex Needs to Understand All the Players // Front Synaptic Neurosci. 2017. Feb 1. V. 9. № 2. Published online PMCID: PMC5285384. doi: 10.3389/fnsyn.2017.00002
- Balaban P.M. Molekuljarnye mehanizmy modifikacii pamjati // Zhurnal vysshej nervnoj dejatel'nosti im. I.P. Pavlova. 2017. T. 67. № 2. S. 131–140.
- Bal N., Roshchin M., Salozhin S., Balaban P. Nitric Oxide Upregulates Proteasomal Protein Degradation in Neurons // Cell Mol. Neurobiol. 2017. V. 45. № 5. P. 643–647.
- Balaban P.M., Roshchin M., Timoshenko A.K., Gainutdinov K.L., Bogodvid T.K., Muranova L.N., Zuzina A.B., Korshunova T.A. Nitric oxide is necessary for labilization of a consolidated context memory during reconsolidation in terrestrial snails // Eur. J. Neurosci. 2014. V. 40. P. 2963–2970.
- Garthwaite J. From synaptically localized to volume transmission by nitric oxide // J. Physiol. 2016. V. 594. № 1. P. 9–18. doi: 10.1113/JP270297.
- Lemak M.S., Bravarenko N.I., Bobrov M.Y., Bezuglov V.V., Ierusalimsky V.N., Storozhuk M.V., Malyshev A.Y., Balaban P.M. Cannabinoid regulation in identified synapse of terrestrial snail // Eur. J. Neurosci. 2007. Dec. 26. № 11. P. 3207–3214.