Memristive neuromorphic circuit design inspired by the neural mechanisms of conditioned fear.

Abstract

Inspired by the neural mechanisms of conditioned fear, this paper designs a memristive neuromorphic circuit based on the Pavlovian associative memory experiment to simulate the functions of learning, forgetting, long-term memory, formation and regulation of conditioned fear, generalization and differentiation, as well as the nested generalization and differentiation. The circuit mainly consists of three modules: the Pavlovian associative memory module, the conditioned fear associative memory and fear regulation module, and the generalization and differentiation module. The Pavlovian associative memory module simulates the process of forming long-term memory through repeated associative learning between food and ring. It achieves a biological mechanism in which the natural forgetting rate approaches zero, while the forgetting rate decreased significantly under the ring stimulus. The conditioned fear associative memory and fear regulation module simulates the formation of conditioned fear, and the fear signal disconnects the synaptic between the ring and the salivation neuron, thereby inhibiting the secretion of salivary neuron. The last module simulates the generalization and differentiation processes for food-ring association and conditioned fear, and it implements the nesting of generalization and differentiation. The correctness and effectiveness of the circuit are verified through PSPICE simulations. Monte Carlo analysis and temperature analysis are operated to demonstrate the robustness of the circuit.