Classical Conditioning and the Planarian

  • Allan L. Jacobson


In several previous papers (1963, 1965, and 1966), I have compiled and attempted to evaluate the evidence for learning in planarians. During the last few years, several particularly convincing demonstrations have all but laid to rest the notion advocated by at least a few scientists that, because of its simple organization, the planarian must be entirely ineducable. This position, however reasonable on a priori grounds, must eventually yield to empirical evidence. And, as Warren has stated, “Overall, the evidence suggests very strongly that learning occurs in flatworms” (1965, p. 100).


Conditioned Stimulus Unconditioned Stimulus Classical Conditioning Galvanic Skin Response Conditioning Procedure 
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Copyright information

© Springer Science+Business Media New York 1967

Authors and Affiliations

  • Allan L. Jacobson
    • 1
  1. 1.Department of PsychologyUniversity of CaliforniaLos AngelesUSA

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