Humidity‐Induced Protein‐Based Artificial Synaptic Devices for Neuroprosthetic Applications

Abstract

Neuroprosthetics and brain–machine interfaces are immensely beneficial for people with neurological disabilities, and the future generation of neural repair systems will utilize neuromorphic devices for the advantages of energy efficiency and real‐time performance abilities. Conventional synaptic devices are not compatible to work in such conditions. The cerebrospinal fluid (CSF) in the central part of the nervous system is composed of 99% water. Therefore, artificial synaptic devices, which are the fundamental component of neuromorphic devices, should resemble biological nerves while being biocompatible, and functional in high‐humidity environments with higher functional stability for real‐time applications in the human body. In this work, artificial synaptic devices are fabricated based on gelatin‐PEDOT: PSS composite as an active material to work more effectively in a highly humid environment (≈90% relative humidity). These devices successfully mimic various synaptic properties by the continuous variation of conductance, like, excitatory/inhibitory post‐synaptic current(EPSC/IPSC), paired‐pulse facilitation/depression(PPF/PPD), spike‐voltage dependent plasticity (SVDP), spike‐duration dependent plasticity (SDDP), and spike‐rate dependent plasticity (SRDP) in environments at a relative humidity levels of ≈90%.