Autapse-inspired neuromorphic hardware with synapse–neuron integration for bidirectional feedback control

Abstract Establishing autonomous and energy-efficient feedback control at the hardware level remains challenging because conventional systems rely on centralized processing and continuous external computation, increasing energy consumption and system complexity. Here we show a neuromorphic autapse-inspired system that enables localized and bidirectional feedback control, using thermoregulation as a representative application. An autapse is a self-synaptic connection in which a neuron feeds its output back to its own synaptic input, enabling intrinsic feedback modulation. The system integrates a solid electrolyte-based synaptic transistor capable of multiplexing multiple inputs and a bidirectional leaky integrate-and-fire artificial neuron. By feeding the neuronal output back to an additional synaptic gate, excitatory and inhibitory feedback loops are realized within a compact architecture. Using an artificial thermoregulation platform, temperature-dependent inputs bidirectionally modulate neuronal firing frequency, demonstrating biologically inspired feedback control with a compact set of neuromorphic devices for autonomous and energy-efficient systems.