The Role of the Basal Ganglia in Exploratory Behavior in a Model Based on Reinforcement Learning

  • Sridharan Devarajan
  • P. S. Prashanth
  • V. S. Chakravarthy
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3316)


We present a model of basal ganglia as a key player in exploratory behavior. The model describes exploration of a virtual rat in a simulated “water pool” experiment. The virtual rat is trained using a reward-based or reinforcement learning paradigm which requires units with stochastic behavior for exploration of the system’s state space. We model the STN-GPe system as a pair of neuronal layers with oscillatory dynamics, exhibiting a variety of dynamic regimes like chaos, traveling waves and clustering. Invoking the property of chaotic systems to explore a state space, we suggest that the complex “exploratory” dynamics of STN-GPe system in conjunction with dopamine-based reward signaling present the two key ingredients of a reinforcement learning system.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Sridharan Devarajan
    • 1
  • P. S. Prashanth
    • 1
  • V. S. Chakravarthy
    • 1
  1. 1.Department of Aerospace Engineering and Department of Electrical EngineeringIndian Institute of TechnologyMadrasIndia

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