Entorhinal Place Cells: Trajectory Encoding

  • Loren M. Frank
  • Emery N. Brown
  • Matthew A. Wilson


If an animal is to successfully navigate through its environment it must not only know where it is, but also where it has been, where it should go, and the relationship among positions in its environment. An animal scavenging for food, for example, needs to remember the set of locations it has visited so that it does waste time retracing its steps. In addition, unless food is randomly scattered through the environment, the animal must be able to learn and remember the locations that are most likely to contain food. Furthermore, the animal must know the relationship between its current position and those locations so that it can plan and execute the movements necessary for it to reach its goals. Our task, then, is to relate neural activity in the brain to the specific requirements of goal directed navigation: knowledge of current, past, and future position, and knowledge of the relationships among positions. Here we will examine how a rat’s movements through its environment relate to neural activity in the CA1 region of the hippocampus and in the entorhinal cortex, the primary source of neocortically derived input to the hippocampus and the primary target of neocortically bound hippocampal outputs.


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Copyright information

© Springer Science+Business Media New York 2002

Authors and Affiliations

  • Loren M. Frank
    • 1
  • Emery N. Brown
    • 1
  • Matthew A. Wilson
    • 2
  1. 1.Massachusetts General HospitalUSA
  2. 2.Massachusetts Institute of TechnologyUSA

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