Samani Mohsen Mosayebi, Mahnam Amin, Hosseini Nasrin
Department of Biomedical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran ; Medical Image and Signal Processing Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
J Med Signals Sens. 2014 Apr;4(2):94-102.
Portable wireless neuro-stimulators have been developed to facilitate long-term cognitive and behavioral studies on the central nervous system in freely moving animals. These stimulators can provide precisely controllable input(s) to the nervous system, without distracting the animal attention with cables connected to its body. In this study, a low power backpack neuro-stimulator was developed for animal brain researches that can provides arbitrary stimulus waveforms for the stimulation, while it is small and light weight to be used for small animals including rats. The system consists of a controller that uses an RF link to program and activate a small and light microprocessor-based stimulator. A Howland current source was implemented to produce precise current controlled arbitrary waveform stimulations. The system was optimized for ultra-low power consumption and small size. The stimulator was first tested for its electrical specifications. Then its performance was evaluated in a rat experiment when electrical stimulation of medial longitudinal fasciculus induced circling behavior. The stimulator is capable of delivering programmed stimulations up to ± 2 mA with adjusting steps of 1 μA, accuracy of 0.7% and compliance of 6 V. The stimulator is 15 mm × 20 mm × 40 mm in size, weights 13.5 g without battery and consumes a total power of only 5.l mW. In the experiment, the rat could easily carry the stimulator and demonstrated the circling behavior for 0.1 ms current pulses of above 400 μA. The developed system has a competitive size and weight, whereas providing a wide range of operation and the flexibility of generating arbitrary stimulation patterns ideal for long-term experiments in the field of cognitive and neuroscience research.
便携式无线神经刺激器已被开发出来，以促进对自由活动动物中枢神经系统的长期认知和行为研究。这些刺激器可以向神经系统提供精确可控的输入，而不会因连接到动物身体的电缆分散其注意力。在本研究中，开发了一种用于动物脑研究的低功耗背包式神经刺激器，它可以为刺激提供任意刺激波形，同时体积小、重量轻，可用于包括大鼠在内的小型动物。该系统由一个控制器组成，该控制器使用射频链路对基于微处理器的小型轻便刺激器进行编程和激活。实现了一个霍兰德电流源以产生精确电流控制的任意波形刺激。该系统针对超低功耗和小尺寸进行了优化。首先对刺激器的电气规格进行了测试。然后在大鼠实验中评估其性能，当时内侧纵束的电刺激诱发了转圈行为。该刺激器能够提供高达±2 mA的编程刺激，调节步长为1 μA，精度为0.7%，顺应性为6 V。刺激器尺寸为15 mm×20 mm×40 mm，无电池时重量为13.5 g，总功耗仅为5.1 mW。在实验中，大鼠可以轻松携带刺激器，并在400 μA以上的0.1 ms电流脉冲下表现出转圈行为。所开发的系统具有竞争力的尺寸和重量，同时提供广泛的操作范围和生成任意刺激模式的灵活性，非常适合认知和神经科学研究领域的长期实验。
