Context Dependent Modulation of Activation Function
Authors: Long Sha, Jonathan Schwarcz, Pengyu Hong
Keywords: Artificial Neural Network, Convolution Neural Network, Long Short-Term Memory, Activation Function, Neuromodulation
TL;DR: We propose a modification to traditional Artificial Neural Networks motivated by the biology of neurons to enable the shape of the activation function to be context dependent.
Abstract: We propose a modification to traditional Artificial Neural Networks (ANNs), which provides the ANNs with new aptitudes motivated by biological neurons.  Biological neurons work far beyond linearly summing up synaptic inputs and then transforming the integrated information.  A biological neuron change firing modes accordingly to peripheral factors (e.g., neuromodulators) as well as intrinsic ones.  Our modification connects a new type of ANN nodes, which mimic the function of biological neuromodulators and are termed modulators, to enable other traditional ANN nodes to adjust their activation sensitivities in run-time based on their input patterns.  In this manner, we enable the slope of the activation function to be context dependent.  This modification produces statistically significant improvements in comparison with traditional ANN nodes in the context of Convolutional Neural Networks and Long Short-Term Memory networks.