Animal Learning & Behavior

, Volume 27, Issue 4, pp 391–398 | Cite as

Overshadowing in the spatial domain

  • J. Sánchez-Moreno
  • T. Rodrigo
  • V. D. Chamizo
  • N. J. Mackintosh


In Experiments 1 and 2, rats were trained in a Morris water maze to locate a hidden platform, the location of which in the circular pool was defined by four visual landmarks (A, B, C, and D), spaced at equal intervals around the edge of the pool. Control animals were trained with these four visual landmarks only. But for animals in the overshadowing groups, an auditory component, X, was added to Landmark D. Test trials, given at the end of training, consisted of placing the rat in the pool with no platform present and recording the time rats spent in the platform quadrant. In Experiment 1, the overshadowing group spent less time in the platform quadrant than controls when tested with D, but the two groups performed equally well on test trials that did not use D. We conclude that the auditory Component X overshadowed the visual Landmark D. In Experiment 2, we obtained evidence of reciprocal overshadowing, of D by X and of X by D. The results of Experiment 3 suggested that an appeal to generalization decrement might not be sufficient to explain these overshadowing effects.


Test Trial Taste Aversion Swimming Pool Animal Behavior Process Hide Platform 
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  1. Biegler, R., &Morris, R. G. M. (1999). Blocking in the spatial domain with arrays of discrete landmarks.Journal of Experimental Psychology: Animal Behavioral Processes,25, 334–351.CrossRefGoogle Scholar
  2. Blaisdell, A. P., Denniston, J. C., &Miller, R. R. (1998). Temporal encoding as a determinant of overshadowing.Journal of Experimental Psychology: Animal Behavior Processes,24, 72–83.PubMedCrossRefGoogle Scholar
  3. Chamizo, V. D., Sterio, D., &Mackintosh, N. J. (1985). Blocking and overshadowing between intra-maze and extra-maze cues: A test of the independence of locale and guidance learning.Quarterly Journal of Experimental Psychology,37B, 235–253.Google Scholar
  4. Mackintosh, N. J. (1976). Overshadowing and stimulus intensity.Animal Learning & Behavior,4, 186–192.Google Scholar
  5. March, J., Chamizo, V. D., &Mackintosh, N. J. (1992). Reciprocal overshadowing between intra-maze and extra-maze cues.Quarterly Journal of Experimental Psychology,45B, 49–63.Google Scholar
  6. Miles, C. G., &Jenkins, H. M. (1973). Overshadowing in operant conditioning as a function of discriminability.Learning & Motivation,4, 11–27.CrossRefGoogle Scholar
  7. Morris, R. G. M. (1981). Spatial localization does not require the presence of local cues.Learning & Motivation,12, 239–260.CrossRefGoogle Scholar
  8. Morris, R. G. M., Garrud, P., Rawlins, J. N. P., &O’Keefe, J. (1982). Place navigation impaired in rats with hippocampal lesions.Nature,297, 681–683.PubMedCrossRefGoogle Scholar
  9. O’Keefe, J., &Conway, D. H. (1978). Hippocampus place units in the freely moving rat: Why they fire where they fire.Experimental Brain Research,31, 573–590.Google Scholar
  10. O’Keefe, J., &Nadel, L. (1978).The hippocampus as a cognitive map. Oxford: Oxford University Press, Clarendon Press.Google Scholar
  11. Pearce, J. M. (1987). A model for stimulus generalization in Pavlovian conditioning.Psychological Review,94, 61–73.PubMedCrossRefGoogle Scholar
  12. Pearce, J. M. (1994). Similarity and discrimination: A selective review and a connectionist model.Psychological Review,101, 587–607.PubMedCrossRefGoogle Scholar
  13. Revusky, S. (1971). The role of interference in association over a delay. In W. K. Honig & P. H. R. James (Eds.),Animal memory (pp. 155–214). New York: Academic Press.Google Scholar
  14. Roberts, A. D. L., &Pearce, J. M. (1999). Blocking in the Morris swimming pool.Journal of Experimental Psychology: Animal Behavior Processes,25, 225–235.PubMedCrossRefGoogle Scholar
  15. Rodrigo, T., Chamizo, V. D., McLaren, I. P. L., &Mackintosh, N. J. (1997). Blocking in the spatial domain.Journal of Experimental Psychology: Animal Behavior Processes,23, 110–118.PubMedCrossRefGoogle Scholar
  16. Sansa, J., Chamizo, V. D., &Mackintosh, N. J. (1996). Aprendizaje perceptivo en discriminaciones espaciales [Perceptual learning in spatial discriminations].Psicológica,17, 279–295.Google Scholar
  17. Shanks, D. R. (1995).Human associative learning. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
  18. Spetch, M. L. (1995). Overshadowing in landmark learning: Touchscreen studies with pigeons and humans.Journal of Experimental Psychology: Animal Behavior Processes,21, 166–181.PubMedCrossRefGoogle Scholar
  19. Sutherland, R. J., Whishaw, I. Q., &Kolb, B. (1982). A behavioral analysis of spatial localization following electrolytic, kainate- or colchicine-induced damage to the hippocampal formation in the rat.Behavioural Brain Research,7, 133–153.CrossRefGoogle Scholar
  20. Wagner, A. R. (1969). Incidental stimuli and discrimination learning. In R. M. Gilbert and N. S. Sutherland (Eds.),Animal discrimination learning (pp. 83–111). London: Academic Press.Google Scholar

Copyright information

© Psychonomic Society, Inc. 1999

Authors and Affiliations

  • J. Sánchez-Moreno
  • T. Rodrigo
    • 1
  • V. D. Chamizo
    • 1
  • N. J. Mackintosh
    • 2
  1. 1.Laboratori de Psicologia Animal i EstabulariUniversitat de BarcelonaBarcelonaSpain
  2. 2.University of CambridgeCambridgeEngland

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