A novel rat robot controlled by electrical stimulation of the nigrostriatal pathway

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Artificial manipulation of animal movement could offer interesting advantages and potential applications using the animal’s inherited superior sensation and mobility. Although several behavior control models have been introduced, they generally epitomize virtual reward-based training models. In this model, rats are trained multiple times so they can recall the relationship between cues and rewards. It is well known that activation of one side of the nigrostriatal pathway (NSP) in the rat induces immediate turning toward the contralateral side. However, this NSP stimulation–induced directional movement has not been used for the purpose of animal-robot navigation. In this study, the authors aimed to electrically stimulate the NSP of conscious rats to build a command-prompt rat robot.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>Repetitive NSP stimulation at 1-second intervals was applied via implanted electrodes to induce immediate contraversive turning movements in 7 rats in open field tests in the absence of any sensory cues or rewards. The rats were manipulated to navigate from the start arm to a target zone in either the left or right arm of a T-maze. A leftward trial was followed by a rightward trial, and each rat completed a total of 10 trials. In the control group, 7 rats were tested in the same way without NSP stimulation. The time taken to navigate the maze was compared between experimental and control groups.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>All rats in the experimental group successfully reached the target area for all 70 trials in a short period of time with a short interstimulus interval (&lt; 0.7 seconds), but only 41% of rats in the control group reached the target area and required a longer period of time to do so. The experimental group made correct directional turning movements at the intersection zone of the T-maze, taking significantly less time than the control group. No significant difference in navigation duration for the forward movements on the start and goal arms was observed between the two groups. However, the experimental group showed quick and accurate movement at the intersection zone, which made the difference in the success rate and elapsed time of tasks.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>The results of this study clearly indicate that a rat-robot model based on NSP stimulation can be a practical alternative to previously reported models controlled by virtual sensory cues and rewards.</jats:p></jats:sec>

Progress of Micro-Stimulation Techniques to Alter Pigeons’ Motor Behavior: A Review from the Perspectives of the Neural Basis and Neuro-Devices

“…Different types of stimulation signals applied to specific brain regions can be used to induce the expected motion of pigeons. Due to the similarity between artificial electrical stimulation signals and spontaneous neural activity, along with the mature easy-to-use devices and control platforms, electrical stimulation-based control with strong sensitivity and high repeatability remains the mainstream mode in current research [58]. In early studies, single constant voltage signals were used in the design of electrical stimulation parameters.…”

Motor Behavior Regulation of Rat Robots Using Integrated Electrodes Stimulated by Micro-Nervous System

“…Due to their excellent biocompatibility and compliance with resistance and toughness requirements, metal microelectrodes are widely applied in animal robotics research. For rat robots, the electrical stimulation sites investigated mainly encompass the MFB, which is used to elicit virtual rewards and propel rats forward [23], and the SIBF, ventral posteromedial nucleus (VPL), ventral posteromedial nucleus (VPM) [24], and nigrostriatal pathway (NSP) [25,26], which are utilized for left-right turning control. Therefore, the implantation of electrodes is required at multiple stimulation sites.…”