A neuromorphic device mimicking synaptic plasticity under different body fluid K⁺ homeostasis for artificial reflex path construction and pattern recognition

The ionic environment of body fluids influences nervous functions for maintaining homeostasis in organisms and ensures normal perceptual abilities and reflex activities. Neural reflex activities, such as limb movements, are closely associated with potassium ions (K⁺). In this study, we developed artificial synaptic devices based on ion concentration–adjustable gels for emulating various synaptic plasticities under different K⁺ concentrations in body fluids. In addition to performing essential synaptic functions, potential applications in information processing and associative learning using short- and long-term plasticity realized using ion concentration–adjustable gels are presented. Artificial synaptic devices can be used for constructing an artificial neural pathway that controls artificial muscle reflex activities and can be used for image pattern recognition. All tests show a strong relationship with ion homeostasis. These devices could be applied to neuromorphic robots and human-machine interfaces.