Effects Of Electric Stimulation Of Basal Nucleus On Somatic Movement In Gekko Gecko

Gekko gecko mainly lives in Yun nan,Guang xi,Guang dong, Fu jian Province in China. They could climb on various surfaces at any angle. It has been become an ideal model for the biorobot research. From 1990's the biorobots become a hotspot in the robotic field. By implanting a chip or a set of microelectrodes in the animal's brain, people can control its behaviors to some extention and use it to finish some dangerous tasks which human beings can not do. In this paper, in order to develop biorobot gecko, we studied the motor function of gecko's basal ganglia from the following several aspects:1. Breeding animals in Nanjing Lab. It is difficult to raising Gekko geckos in Nanjing due to the climate difference between Jiang su and Guang xi Provice. After two years'house-raising of Gekko gecko, we obtained several skills in feeding, breeding, disease prevention and so on.2. Motor function studies of the gecko's basal nucleus by electric stimulation and lesion method. The electric stimulation study maily contains acute anesthesia experiment and chronic awake experiment. In the acute experiment, we maily studied the motor function of basal nucleus using electric stimulation method, we also investigated the cortex dorsalis,nucleus accumbens,nucleus sphericus,nucleus of the diagonal band of Broca and the septum. The stimulation signals were unipolar square pulses with amplitude 0.12 mA, frequency 80 Hz, and duration 1 ms. The results showed that electric stimulation of medial striatum, dorsal striatum and central striatum could induce gecko's tongue flicking ,about 5 s after simulation(Rate>80%), electric stimulation of ventral part of nucleus septalis lateral and lateral forebrain bundle could induce its backbone bending (Rate=30%), and electric stimulation of ventral part of nucleus septalis medialis and medial forebrain bundle could induce gecko's legs moving(Rate=50%).In the chronic experiment, we mainly implanted microelectrodes into the basal nucleus and nucleus septalis, then used the electrical stimulation to study the motor function of them,and compare the results with the acute experimental results. The stimulation signals were unipolar square pulses with amplitude 0.1 mA, frequency 80 Hz, and duration 1 ms. The results suggested that electric stimulation of medial striatum could induce gecko's tongue flicking (toward the same side of stimulation), several seconds after stimulation, electric stimulation of nucleus septalis could induce the head turning ipsilateral.3.Then lesion the basal ganglia by direct current, the destruction parameter is 0.5 mA, 30 s. After 8 days observation (4 days before operation and 4 days after operation) the control animal's decrement of the total length of movement is 37.0%; the first test animal's decrement of the total length of movement is 74.7% and the second is 91.6%.4.Study on the afferent connections of the striatum of the lizard Gekko gecko. They were studied with retrograde tracing by means of horseradish peroxidase. After injection into the medial striatum we found the striatum receives projections from the dorsal cortex,lateral cortex, the amygdaloid nucleus, the globus pallidus,the accumbens nucleus, the tuberculum olfactorium and so on. All the projection are ipsilateral.Our study suggested that gecko's basal nucleus played the role in the gecko's locomotion modulation.The activity of dorsal cortex,lateral cortex, the amygdaloid nucleus, the globus pallidus,the accumbens nucleus, the tuberculum olfactorium and so on is related to the medial striatum.