Rahiminejad Ehsan, Azad Fatemeh, Parvizi-Fard Adel, Amiri Mahmood, Linares-Barranco Bernabe
IEEE Trans Neural Netw Learn Syst. 2022 May;33(5):2246-2258. doi: 10.1109/TNNLS.2020.3045019. Epub 2022 May 2.
Neurophysiological observations confirm that the brain not only is able to detect the impaired synapses (in brain damage) but also it is relatively capable of repairing faulty synapses. It has been shown that retrograde signaling by astrocytes leads to the modulation of synaptic transmission and thus bidirectional collaboration of astrocyte with nearby neurons is an important aspect of self-repairing mechanism. Specifically, the retrograde signaling via astrocyte can increase the transmission probability of the healthy synapses linked to the neuron. Motivated by these findings, in the present research, a CMOS neuromorphic circuit with self-repairing capabilities is proposed based on astrocyte signaling. In this way, the computational model of self-repairing process is hired as a basis for designing a novel analog integrated circuit in the 180-nm CMOS technology. It is illustrated that the proposed analog circuit is able to successfully recompense the damaged synapses by appropriately modifying the voltage signals of the remaining healthy synapses in the wide range of frequency. The proposed circuit occupies 7500- [Formula: see text] silicon area and its power consumption is about [Formula: see text]. This neuromorphic fault-tolerant circuit can be considered as a key candidate for future silicon neuronal systems and implementation of neurorobotic and neuro-inspired circuits.
神经生理学观察证实，大脑不仅能够检测受损的突触（在脑损伤中），而且相对能够修复有缺陷的突触。研究表明，星形胶质细胞的逆行信号传导会导致突触传递的调节，因此星形胶质细胞与附近神经元的双向协作是自我修复机制的一个重要方面。具体而言，通过星形胶质细胞的逆行信号传导可以增加与神经元相连的健康突触的传递概率。受这些发现的启发，在本研究中，基于星形胶质细胞信号传导提出了一种具有自我修复能力的CMOS神经形态电路。通过这种方式，将自我修复过程的计算模型用作在180纳米CMOS技术中设计新型模拟集成电路的基础。结果表明，所提出的模拟电路能够通过在很宽的频率范围内适当修改其余健康突触的电压信号来成功补偿受损突触。所提出的电路占用7500 - [公式：见原文] 的硅面积，其功耗约为 [公式：见原文]。这种神经形态容错电路可被视为未来硅神经元系统以及神经机器人和神经启发电路实现的关键候选者。
