The simulation of human feelings, perceptions, and actions has become an important application field for medical treatment, human-computer interfaces, and intelligent robots. However, the need for various functional units hinders system integration. A threshold-switching memristor is used as the sympathetic nerve center to simulate an unconditioned reflex. High current nonlinearity (10(6)) is achieved by adopting a nanocontact structure, and high flexibility (bending radius of approximate to 5 mm) is obtained by combining the structure with a flexible polymer film. Furthermore, integrating a flexible sensor and a flexible artificial muscle made of ionic polymer-metal composite allows to form an all-flexible complete reflex arc of an unconditioned reflex. The threshold-switching memristor can provide strain-dependent control through simple control logic, indicating the great potential of adopting threshold-switching memristors for primary neuromorphological control and flexible intelligent medical treatment.