Animal Cognition

, Volume 16, Issue 2, pp 177–186 | Cite as

Cue competition effects in the planarian

  • Jose PradosEmail author
  • Beatriz Alvarez
  • Joanna Howarth
  • Katharine Stewart
  • Claire L. Gibson
  • Claire V. Hutchinson
  • Andrew M. J. Young
  • Colin Davidson
Original Paper


The learning abilities of planarian worms (Dugesia tigrina) were assessed by using a number of Pavlovian conditioning paradigms. Experiment 1 showed that planaria were susceptible to basic conditioning in that they readily developed a conditioned response to a change in ambient luminance when it was consistently paired with an electric shock over a number of trials. In Experiment 2, the change in luminance was presented in a compound with a vibration stimulus during conditioning. Subsequent tests revealed poor conditioning of the elements compared with control groups in which the animals were conditioned in the presence of the elements alone, an instance of overshadowing. In Experiment 3, pre-training of one of the elements before compound conditioning resulted in blocking of learning about the other element. These results add to other studies that have reported cue competition effects in animal species belonging to different phyla (chordate, mollusk, arthropod), suggesting that learning in these phyla could be ruled by similar principles. The results are discussed adopting an evolutionary-comparative approach.


Invertebrate learning Pavlovian conditioning Overshadowing Blocking 



The present research was supported by an NC3Rs-LASA (UK) Small Award to the authors.


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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Jose Prados
    • 1
    Email author
  • Beatriz Alvarez
    • 1
    • 2
  • Joanna Howarth
    • 1
  • Katharine Stewart
    • 1
  • Claire L. Gibson
    • 1
  • Claire V. Hutchinson
    • 1
  • Andrew M. J. Young
    • 1
  • Colin Davidson
    • 3
  1. 1.School of PsychologyUniversity of LeicesterLeicesterUK
  2. 2.Facultad de PsicologíaUniversidad de OviedoOviedoSpain
  3. 3.Basic Medical SciencesSt George’s University of LondonLondonUK

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