本文采用集成有射频功能的片上系统(nRF24E1),研制了一种用于自由活动小动物的微型多模式遥控刺激器。刺激参数的设置及结果分析均由10m外的个人计算机进行。通过离体实验,即刺激蛙坐骨神经干时产生动作电位并可观察到伪迹;及在体大鼠的训练操作性条件反射的行为学实验,即在Y臂迷宫中训练大鼠听到不同声音完成左右运动,如果完成正确给予前脑内侧束以电刺激,我们观察到5d内大鼠的正确率增加3倍,达到93.5%。上述实验都验证了该刺激器的有效性与稳定性。本系统具有体积小(18mm×28mm双层线路板)、重量轻(不含电池5g)、简单、实用、可靠等特点,能有效地用于自由活动小动物的实验研究。为基于电刺激的小动物行为训练(动物机器人)及相关神经生理学实验研究,提供了新的实验条件和实验手段。
This paper presents a remote controlled multimode micro-stimulator based on the chip nRF24E1, which consists mainly of a micro-control unit (MCU) and a radio frequency (RF) transceiver. This micro-stimulator is very compact (18 mm×28 mm two layer printed circuit board) and light (5 g without battery), and can be carried on the back of a small animal to generate electrical stimuli according to the commands sent from a PC 10 meters away. The performance and effectiveness of the micro-stimulator were validated by in vitro experiments on the sciatic nerve (SN) of the frog, where action potentials (APs) as well as artifacts were observed when the SN was stimulated by the micro-stimulator. It was also shown by in vivo behavioral experiments on operant conditioned reflexes in rats which can be trained to obey auditory instruction cues by turning right or left to receive electrical stimulation (‘virtual' reward) of the medial forebrain bundle (MFB) in a maze. The correct response for the rats to obey the instructions increased by three times and reached 93.5% in an average of 5 d. This micro-stimulator can not only be used for training small animals to become an 'animal robots', but also provide a new platform for behavioral and neurophysiological experiments.