Artificial Astrocytes Improve Neural Network Performance

Abstract

Compelling evidence indicates the existence of bidirectional communication between astrocytes and neurons. Astrocytes, a type of glial cells classically considered to be passive supportive cells, have been recently demonstrated to be actively involved in the processing and regulation of synaptic information, suggesting that brain function arises from the activity of neuron-glia networks. However, the actual impact of astrocytes in neural network function is largely unknown and its application in artificial intelligence remains untested. We have investigated the consequences of including artificial astrocytes, which present the biologically defined properties involved in astrocyte-neuron communication, on artificial neural network performance. Using connectionist systems and evolutionary algorithms, we have compared the performance of artificial neural networks (NN) and artificial neuron-glia networks (NGN) to solve classification problems. We show that the degree of success of NGN is superior to NN. Analysis of performances of NN with different number of neurons or different architectures indicate that the effects of NGN cannot be accounted for an increased number of network elements, but rather they are specifically due to astrocytes. Furthermore, the relative efficacy of NGN vs. NN increases as the complexity of the network increases. These results indicate that artificial astrocytes improve neural network performance, and established the concept of Artificial Neuron-Glia Networks, which represents a novel concept in Artificial Intelligence with implications in computational science as well as in the understanding of brain function.

Astrocyte-Synapse Receptor Coupling in Tripartite Synapses: A Mechanism for Self-Observing Robots

“…Based on physiological or biophysical experiments mathematical modeling and computer simulations will probably be helpful for testing predictions on functions of astrocytes in neuronal networks [27]. Such simulations may also give rise to new ideas concerning the role of astrocytes in…”

Zur Entstehung des Bewusstseins: Hypothese zur Rolle von Gliazellen, verzweigten Nervenenden und Dendritenarmen

“…Es wird ein enger Zusammenhang zwischen Gliazellen und Intelligenz vermutet [34,35]: Je höher die phylogenetische Entwicklung des Tieres, desto mehr Astrozyten kommen durchschnittlich auf eine Nervenzelle. Beim Wurm sind es beispielsweise lediglich 0,17 Astrozyten pro Nervenzelle, beim Frosch 0,5, bei der Katze ca.…”

<strong>Computational Models of the Brain</strong>

“…There are only realistic computational models [42][43][44][45][46][47][48][49] and connectionist ones [50][51][52][53][54] which have taken glial cells into account. Currently, there are two projects aimed at implementing astrocytes in neuromorphic chips, one is BioRC [55][56][57] developed by the University of Southern California and the other project is carried out by the University of Tehran and University of Kermanshah (Iran) [58][59][60].…”