Page 132 - Artificial Intelligence in the Age of Neural Networks and Brain Computing
P. 132

3. Spiking Neural Networks (SNN) as Brain-Inspired ANN    121




                  •  An evolving fuzzy neural network based on the mapping of similarities [87];
                  •  Incremental learning by heterogeneous bagging ensemble [88];
                  •  Fuzzy associative conjuncted maps network [89];
                  •  EFuNN ensembles construction using CONE with multiobjective GA [90];
                  •  Risk analysis and discovery of evolving economic clusters in Europe [91];
                  •  Adaptive time-series prediction for financial applications [92];
                  •  Adaptive speech recognition [93];
                  •  and others [37].

                     ECOS methods and systems presented above use predominantly the McCulloch
                  and Pitts model of a neuron (Fig. 6.2A). They have been efficiently used for wide
                  range of applications as some of them listed above.



                  3. SPIKING NEURAL NETWORKS (SNN) AS BRAIN-INSPIRED
                     ANN

                  3.1 MAIN PRINCIPLES, METHODS, AND EXAMPLES OF SNN AND
                      EVOLVING SNN (ESNN)
                  The traditional ANN and ECOS discussed in the previous sections are the theoretical
                  bases on which the third generation of ANN was developed - spiking neural networks
                  (SNN). Spiking neural network (SNN) architectures use a spiking neuron model and
                  spike information representation. Spike information representation accounts for time
                  in the data and for changes in the data over time. This is where SNN can be chosen as
                  preferred methods and used efficiently.
                     A spiking neuron model receives input information represented as trains of spikes
                  over time from many inputs. When sufficient input information is accumulated in the
                  membrane of the neuron, the neuron’s postsynaptic potential exceeds a threshold and
                  the neuron emits a spike at its axon (Fig. 6.6).
                     Some of the state-of-the-art models of a spiking neuron include: early models by
                  Hodgkin and Huxley [94]; Spike Response Models (SRM); Integrate-and-Fire
                  Models (IFM) (Fig. 6.6); Izhikevich models; adaptive IFM; and probabilistic IFM
                  [95,96].












                  FIGURE 6.6
                  The structure of the LIFM of a spiking neuron.
   127   128   129   130   131   132   133   134   135   136   137