Approximation of the effect of an electric field on neurons
For the function that defines the output of a node in artificial neuronal networks according to the given input, see Activation function.
The activating function is a mathematical formalism that is used to approximate the influence of an extracellular field on an axon or neurons.[1][2][3][4][5][6] It was developed by Frank Rattay and is a useful tool to approximate the influence of functional electrical stimulation (FES) or neuromodulation techniques on target neurons.[7] It points out locations of high hyperpolarization and depolarization caused by the electrical field acting upon the nerve fiber. As a rule of thumb, the activating function is proportional to the second-order spatial derivative of the extracellular potential along the axon.
^Rattay, F. (1986). "Analysis of Models for External Stimulation of Axons". IEEE Transactions on Biomedical Engineering (10): 974–977. doi:10.1109/TBME.1986.325670. S2CID 33053720.
^Rattay, F. (1988). "Modeling the excitation of fibers under surface electrodes". IEEE Transactions on Biomedical Engineering. 35 (3): 199–202. doi:10.1109/10.1362. PMID 3350548. S2CID 27312507.
^Rattay, F. (1989). "Analysis of models for extracellular fiber stimulation". IEEE Transactions on Biomedical Engineering. 36 (7): 676–682. doi:10.1109/10.32099. PMID 2744791. S2CID 42935757.
^Rattay, F. (1990). Electrical Nerve Stimulation: Theory, Experiments and Applications. Wien, New York: Springer. pp. 264. ISBN 3-211-82247-X.
^Rattay, F. (1998). "Analysis of the electrical excitation of CNS neurons". IEEE Transactions on Biomedical Engineering. 45 (6): 766–772. doi:10.1109/10.678611. PMID 9609941. S2CID 789370.
^Rattay, F. (1999). "The basic mechanism for the electrical stimulation of the nervous system". Neuroscience. 89 (2): 335–346. doi:10.1016/S0306-4522(98)00330-3. PMID 10077317. S2CID 41408689.
^Danner, S.M.; Wenger, C.; Rattay, F. (2011). Electrical stimulation of myelinated axons. Saarbrücken: VDM. p. 92. ISBN 978-3-639-37082-9.
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The activationfunction of a node in an artificial neural network is a function that calculates the output of the node based on its individual inputs...
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