n-Type Accumulation-Mode Organic Electrochemical Transistors as General Building Blocks for Low-Power Organic Artificial Neurons Enabling Multimodal Sensing Integration

The human integumentary system encodes external stimuli into temporally and spatially patterned spike signals for transmission to the central nervous system. Inspired by this biological process, we present a symmetric cross-coupled organic neuron based on accumulative n-type organic electrochemical transistors (OECTs). By utilizing only two identical n-type accumulation-mode OECTs, our system reproduces ten distinct biologically relevant spiking behaviors and operates robustly across diverse semiconductors and electrolytes, establishing a material-general framework for OECT-based neurons. Its spiking dynamics can be modulated by ionic, optical, and mechanical stimuli. Coupling the low-power neuron with a photodetector further enables light-driven, energy-autonomous operation. The system also enables multimodal sensory integration and selective signal decoupling via frequency-division multiplexing, offering a potential route toward complex sensory processing. Separately, the system achieves functional biological integration by interfacing with Venus flytraps to control leaf closure via artificial spikes. These results establish our materials-versatile strategy as a versatile framework for constructing organic artificial neuromorphic systems, providing a new pathway toward next-generation material-independent neuromorphic architectures, multimodal sensory integration, and bio-interfacing technologies.