Pain‐perceptual nociceptors (PPN) are essential sensory neurons that recognize harmful stimuli and can empower the human body to react appropriately and perceive precisely unusual or dangerous conditions in the real world. Furthermore, the sensitization‐regulated nociceptors (SRN) can greatly assist pain‐sensitive human to reduce pain sensation by normalizing hyperexcitable central neural activity. Therefore, the implementation of PPNs and SRNs in hardware using emerging nanoscale devices can greatly improve the efficiency of bionic medical machines by giving them different sensitivities to external stimuli according to different purposes. However, current most‐normal organic/oxide transistors face a great challenge due to channel scaling, especially in the sub‐10 nm channel technology. Here, a sub‐10 nm indium‐tin‐oxide transistor with an ultrashort vertical channel as low as ≈3 nm, using sodium alginate bio‐polymer electrolyte as gate dielectric, is demonstrated. This device can emulate important characteristics of PPN such as pain threshold, memory of prior injury, and pain sensitization/desensitization. Furthermore, the most intriguing character of SRN can be achieved by tuning the channel thickness. The proposed device can open new avenues for the fascinating applications of next‐generation neuromorphic brain‐like systems, such as bio‐inspired electronic skins and humanoid robots.

Humans can clearly perceive surroundings efficiently while consuming little energy because of human intelligence and powerful vision system. Thus, it has been a long‐sought dream for human beings to build such an energy‐efficient artificial intelligent vision system with emerging devices. Unfortunately, a wearable optoelectronic device for visual nociceptor systems, regarded as a key bionic function to protect the vision, remains to be developed so far. Herein, using the vertical coplanar‐multiterminal flexible transient photogating transistor network with a 3 nm ultrashort channel, a wearable artificial vision system with painful‐perceptual abilities is successfully demonstrated for flexible electronic‐skin (e‐skin) applications. The device not only has the ability of ultrafast transient physical disappearance of only 60 s for information security but also establishes a flexible optical in‐sensor visual nociceptor (ISVN) e‐skin. The optical transition from short‐time memory to long‐time memory of visual memory is educed by a strong photogating effect, and the higher‐level‐graded optical painful alarm‐sensing system is also demonstrated by this flexible artificial e‐skin. Moreover, the proposed devices will achieve painful light sensitization under different spatiotemporal color patterns to avoid external secondary injuries. It provides a good opportunity for future intelligent e‐skin taking advantage of its intriguing visual pain‐perceptual abilities.

Brain‐inspired associative memory is meaningful for pattern recognitions and image/speech processing. Here, a ferroelectric synaptic transistor network is proposed that is capable of associative learning and one‐step recalling of a whole set of data from only partial information. The competition between an external field and the internal depolarization field governs the ferroelectric creep of domain walls and offers each single ferroelectric synapse a full and subfemtojoule‐energy‐cost Hebbian synaptic plasticity, including short‐term memory (STM) to long‐term memory (LTM) transition, and remarkably both spike‐timing‐dependent plasticity (STDP) and spike‐rate‐dependent plasticity (SRDP). Assisted by the third terminal to control the ferroelectric domain dynamics, self‐adaptive coupling between neurons is realized by updating synaptic weight concurrently. Pavlov's dog experiment and multiassociative memories are demonstrated in this ferroelectric synaptic transistor network. Such ferroelectric synaptic transistor network is available for building multilayer neural networks and provides new avenues for associative‐memory information processing.

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