Model neuron

Now, to be sure, McCulloch-Pitts neurons are unrealistically rendered versions of the real thing. For example, the assumption that neuronal firing occurs synchronously throughout the net at well defined discrete points in time is simply wrong. The tacit assumption that the structure of a neural net (i.e. its connectivity, as defined by the set of synaptic weights) remains constant over time is known be false as well. Moreover, while the input-output relationship for real neurons is nonlinear, real neurons are not the simple threshold devices the McCulloch-Pitts model assumes them to be. In fact, the output of a real neuron depends on its weighted input in a nonlinear but continuous manner. Despite their conceptual drawbacks, however, McCulloch-Pitts neurons are nontrivial devices. McCulloch-Pitts were able to show that for a suitably chosen set of synaptic weights wij, a synchronous net of their model neurons is capable of universal computation. This means that, in principle, McCulloch-Pitts nets possess the same raw computational power as a conventional computer (see section 6.4). 

Calon F, l.im GP, Yang F, Morihara T, Teter B, Ubeda O, Rostaing P, Triller A, Salem N Jr, Ashe KH, Frautschy SA, Cole GM. (2004) Docosahexaenoic acid protects from dendritic pathology in an Alzheimer s disease mouse model. Neuron 43 633-645. 

Dauer W, Przedborski S. Parkinson s disease mechanisms and models. Neuron. 2003 39 889-909. 

Seburn, K. L., Nangle, L. A., Cox, G. A., Schimmel, P. and Burgess, R. W. (2006) An active dominant mutation of glycyl-tRNA synthetase causes neuropathy in a Charcot-Marie-Tooth 2D mouse model. Neuron 51, 715-726. 

Postnova, S Wollweber, B., Voigt, K., and Braun, H.A. Impulse-pattern in bidirectionally coupled model neurons of different dynamics. BioSystems, 2007 89 135-172. 

Wilson H. R., Cowan J. D. Excitatory and inhibitory interactions in localized populations of model neurons. Biophys J, 1972, 12,1-24. 

Yoshiyama Y, Higuchi M, Zhang B et al (2007) Synapse loss and microglial activation precede tangles in a P301S tauopathy mouse model. Neuron 53 337-351... 

Canavier, C.C., D.A. Baxter, J.W. Qark J.H. Byrne. 1993. Nonlinear dynamics in a model neuron provide a novel mechanism for transient synaptic inputs to produce long-term alterations of postynaptic activity. J. Neurophysiol. 69 2252-7. 

To test this idea of symmetry breaking with lateral excitation, we have built a full size model of the locust olfactory system using Hodgkin-Huxley type model neurons for PNs, leaky integrate-and-fire neurons for KCs and a single Hodgkin-Huxley neuron to represent the global inhibition from lateral horn interneurons onto the KCs. The KCs... 

F. Calon, et al., Docosahexaenoic Acid Protects From Dendritic Pathology in an Alzheimer s Disease Mouse Model, Neuron 43, no. 5 (2004) 633-645. 

Good, T.A. and R.M. Murphy (1996). Effect of -amyloid block of the fast-inactivating K+ channel on intraceUular Ca + and excitabiUty in a modeled neuron. Proc. Natl Acad. Sci. USA 93, 15130-15135. 

Seipell, L.C., Berriman, 1., lakes, R., et al. Fiber diffraction of S5mthetic alpha-synuclein filaments shows amyloid-like cross-beta conformation. Proc. Natl. Acad. Sci. USA 97,4897-4902 (2000). doi 10.1073/pnas.97.9.4897 Dauer, W., Przedborski, S. Parkinson s Disease Mechanisms and Models. Neuron 39, 889-909 (2003)... 

The basic computational element, or model neuron, can also be called a node or unit. It receives input from one or more other neurons, or perhaps from an external source. Each input has an associated weight which refers to the weight from neuron j of layer (/ -1) to neuron i of layer 1. The random initial value of the weight is modified by model synaptic learning. The neuron computes some activation function /of the weighted sum of its inputs yf. 

Kurulugama, R., Wipf, D. O., Takacs, S., Pongmayteegul, S., Garris, P, Baur, J. E. Scanning elecb-o-chemical microscopy of model neurons Constant distance imaging. Ana/. Chem. 2005, 77,1111-1117. 

Eigure 4.6 shows a representative topographical image of undifferentiated (i.e., no treatment of nerve growth factor, NGE) and differentiated (NGF-treated) PC12 cells (model neurons) recorded... 

Liebetrau JM, Miller HM, Baur JE, Takacs SA, Anupunpisit V, Garris PA, Wipf DO (2003) Scanning electrochemical microscopy of model neurons imaging and real-time detection of morphological changes. Anal Chem 75 563-571... 

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