Perspectives on Behavior Science

, Volume 41, Issue 2, pp 447–464 | Cite as

Behavioral Research with Planaria

  • Neil DeochandEmail author
  • Mack S. Costello
  • Michelle E. Deochand
Learning: No Brain Required


This article serves as a brief primer on planaria for behavior scientists. In the 1950s and 1960s, McConnell’s planarian laboratory posited that conditioned behavior could transfer after regeneration, and through cannibalization of trained planaria. These studies, the responses, and replications have been collectively referred to as the “planarian controversy.” Successful behavioral assays still require refinement with this organism, but they could add valuable insight into our conceptualization of memory and learning. We discuss how the planarian’s distinctive biology enables an examination of biobehavioral interaction models, and what behavior scientists must consider if they are to advance behavioral research with this organism. Suggestions for academics interested in building planaria learning laboratories are offered.


Planaria Invertebrate learning Behavior analysis Conditioning Memory 



The authors thank Rachel L. Burroughs for helping with editing an earlier draft of this manuscript.

Compliance with Ethical Standards


All material contained herein is not plagiarized.

Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

40614_2018_176_MOESM1_ESM.mp4 (21.9 mb)
ESM 1 (MP4 22402 kb)


  1. Abbott, S. M., & Wong, G. K. (2008). The conditioning and memory retention of planaria (Dugesia tigrina) for directional preferences. Bios, 79(4), 160–170.Google Scholar
  2. Abramson, C. I. (2015). A crisis in comparative psychology: Where have all the undergraduates gone? Frontiers in Psychology, 6, 1589. Scholar
  3. Abramson, C. I., & Feinman, R. D. (1990). Lever-press conditioning in the crab. Physiology & Behavior, 48(2), 267–272.Google Scholar
  4. Adell, T., Saló, E., van Loon, J. J., & Auletta, G. (2014). Planarians sense simulated microgravity and hypergravity. BioMed Research International, 1–10.
  5. Akiyama, Y., Agata, K., & Inoue, T. (2015). Spontaneous behaviors and wall-curvature lead to apparent wall preference in planarian. PLoS One, 10, 1–17. Scholar
  6. Allee, W. C., & Wilder, J. (1939). Group protection for Euplanaria dorotocephala from ultra-violet radiation. Physiological Zoology, 12(2), 110–135. Scholar
  7. Allen, G. D. (1915). Reversibility of the reactions of Planaria dorotocephala to a current of water. Biological Bulletin, 29, 111–128. Scholar
  8. American Psychological Association (APA). (2017). Resolution reaffirming support for research and teaching with nonhuman animals. Retrieved from
  9. American Psychological Association (APA). (n.d.). Research animals in psychology. Retrieved from
  10. Auletta, G., Adell, T., Colagè, I., D’Ambrosio, P., & Salò, E. (2012). Space research program on Planarian Schmidtea Mediterranea’s establishment of the anterior-posterior axis in altered gravity conditions. Microgravity Science and Technology, 24, 419–425. Scholar
  11. Azrin, N. H., & Holz, W. C. (1966). Punishment. In W. K. Honig (Ed.), Operant behavior: areas of research and application (pp. 380–447). East Norwalk, CT: Appleton-Century-Crofts.Google Scholar
  12. Barnes, T. C., & Skinner, B. F. (1930). The progressive increase in the geotropic response of the ant Aphaenogaster. The Journal of General Psychology, 4, 102–112.Google Scholar
  13. Baxter, R., & Kimmel, H. D. (1963). Conditioning and extinction in the planarian. American Journal of Psychology, 76, 665–669. Scholar
  14. Best, J. B. (1960). Diurnal cycles and cannibalism in planaria. Science, 131, 1884–1885. Scholar
  15. Best, J. B. (1965). Behavior of planaria in instrumental learning paradigms. Animal Behaviour, 13(Suppl. 1), 69–75.Google Scholar
  16. Best, J. B., & Rubinstein, I. (1962). Environmental familiarity and feeding in a planarian. Science, 135(3507), 916–918.Google Scholar
  17. Bitterman, E. M. (1965). Phyletic differences in learning. American Psychologist, 20, 396–410. Scholar
  18. Blackiston, D., Shomrat, T., Nicolas, C. L., Granata, C., & Levin, M. (2010). A second-generation device for automated training and quantitative behavior analyses of molecularly-tractable model organisms. PLoS One, 5, 1–20. Scholar
  19. Blackiston, D. J., Silva Casey, E., & Weiss, M. R. (2008). Retention of memory through metamorphosis: can a moth remember what it learned as a caterpillar? PLoS One, 3, e1736. Scholar
  20. Block, R. A., & McConnell, J. V. (1967). Classically conditioned discrimination in the Planarian, Dugesia dorotocephala. Nature, 215, 1465–1466.Google Scholar
  21. Bocchinfuso, D. G., Taylor, P., Ross, E., Ignatchenko, A., Ignatchenko, V., Kislinger, T., et al. (2012). Proteomic profiling of the planarian Schmidtea mediterranea and its mucous reveals similarities with human secretions and those predicted for parasitic flatworms. Molecular & Cellular Proteomics, 11, 681–691. Scholar
  22. Boring, E. G. (1912). Notes on the negative reaction under light-adaptation in the planarian. Journal of Animal Behavior, 2(4), 229. Scholar
  23. Branch, M. (2014). Malignant side effects of null-hypothesis significance testing. Theory & Psychology, 24, 256–277. Scholar
  24. Breland, K., & Breland, M. (1961). The misbehavior of organisms. American Psychologist, 16, 681. Scholar
  25. Calvin, O. L., & McDowell, J. J. (2016). Extending unified-theory-of-reinforcement neural networks to steady-state operant behavior. Behavioral Processes, 127, 52–61. Scholar
  26. Chicas-Mosier, A. M., & Abramson, C. I. (2015). A new instrumental/operant conditioning technique suitable for inquiry-based activities in courses on experimental psychology, learning, and comparative psychology using planaria (Dugesia dorotocephala and Dugesia tigrina). Comprehensive Psychology, 4, 1–6. Scholar
  27. Corning, W. C., & Lahue, R. (1972). Invertebrate strategies in comparative learning studies. American Zoologist, 12, 455–469. Scholar
  28. Corning, W. C., & Riccio, D. (1970). The planarian controversy. In W. Bryne (Ed.), Molecular approaches to learning and memory (pp. 107–150). New York, NY: Academic Press.Google Scholar
  29. Crawford, F. T., & Skeen, S. L. C. (1967). Operant responding in the planarian: a replication study. Psychological Reports, 20, 1023–1027. Scholar
  30. Critchfield, T. S. (2011). To a young basic scientist, about to embark on a program of translational research. The Behavior Analyst, 34(2), 137–148.Google Scholar
  31. De Both, N. J. (1968). Transplantation of axolotl heads. Science, 162, 460–461. Scholar
  32. Deochand, N., & Fuqua, R. W. (2016). BACB certification trends: state of the states (1999 to 2014). Behavior Analysis in Practice, 9, 243–252. Scholar
  33. Dexter, J. P., Tamme, M. B., Lind, C. H., & Collins, E. M. S. (2014). On-chip immobilization of planarians for in vivo imaging. Scientific Reports, 4, 1–9. Scholar
  34. Dixon, M. R., Daar, J. H., Gunnarsson, K., Johnson, M. L., & Shayter, A. M. (2016). Stimulus preference and reinforcement effects of the Madagascar hissing cockroach (Gromphordahina portentosa): a case of reverse translational research. The Psychological Record, 66, 41–51. Scholar
  35. Donahoe, J. W., & Palmer, D. C. (2004). Learning and complex behavior. Richmond, MA: Ledgetop Publishing.Google Scholar
  36. Downey, P., & Jahan-Parwar, B. (1972). Cooling as reinforcing stimulus in Aplysia. American Zoologist, 12, 507–512. Scholar
  37. Duhaime-Ross, A. (2015, March 18). Memory in the flesh: a radical 1950’s scientist suggested memories could survive outside the brain—and he may have been right. The Verge. Retrieved August 24, 2018, from
  38. Egger, B., Gschwentner, R., & Rieger, R. (2007). Free-living flatworms under the knife: past and present. Development Genes and Evolution, 217, 89. Scholar
  39. Epstein, R. (1981). On pigeons and people: a preliminary look at the Columban Simulation Project. The Behavior Analyst, 4, 43–55. Scholar
  40. Fiedler, K. (2011). Voodoo correlations are everywhere—not only in neuroscience. Perspectives on Psychological Science, 6, 163–171. Scholar
  41. Fox, A. E. (2018). The future is upon us. Behavior Analysis: Research & Practice, 18, 144–150. Scholar
  42. Garcia, J., Kimeldorf, D. J., & Koelling, R. A. (1955). Conditioned aversion to saccharin resulting from exposure to gamma radiation. Science, 122, 157–158. Scholar
  43. Grossmann, K. E. (1973). Continuous, fixed-ratio, and fixed-interval reinforcement in honey bees. Journal of the Experimental Analysis of Behavior, 20, 105–109. Scholar
  44. Halas, E. S. (1963). Operant conditioning in planaria: a criticism. Science, 141, 390–392. Scholar
  45. Halas, E. S., James, R. L., & Knutson, C. S. (1962). An attempt at classical conditioning in the planarian. Journal of Comparative & Physiological Psychology, 55(6), 969–971. Scholar
  46. Halas, E. S., James, R. L., & Stone, L. A. (1961). Types of responses elicited in planaria by light. Journal of Comparative & Physiological Psychology, 54, 302. Scholar
  47. Hershkowitz, M., Segal, M., & Samuel, D. (1972). The acquisition of dark avoidance by transplantation of the forebrain of trained newts (Pleurodeles waltl). Brain Research, 48, 366–369.Google Scholar
  48. Hoffman, H. S., & Fleshler, M. (1959). Aversive control with the pigeon. Journal of the Experimental Analysis of Behavior, 2, 213–218. Scholar
  49. Jacobson, A. L., Horowitz, S. D., & Fried, C. (1967). Classical conditioning, pseudoconditioning, or sensitization in the planarian. Journal of Comparative & Physiological Psychology, 64(1), 73.Google Scholar
  50. Jenkins, M. M. (1967). Aspects of planarian biology and behavior. In W. C. Corning & S. C. Ratner (Eds.), Chemistry of learning (pp. 116–143). New York, NY: Plenum Press.Google Scholar
  51. Katz, A. N. (1978). Inexpensive animal learning exercises for huge introductory laboratory classes. Teaching of Psychology, 5(2), 91–93. Scholar
  52. Krantz, M. L. (1964). Operant conditioning of planarians. Beta Beta Beta Biological Society, 35(3), 139–141.Google Scholar
  53. Lattal, K. A. (2001). The human side of animal behavior. The Behavior Analyst, 24, 147–161. Scholar
  54. Lee, R. M. (1963). Conditioning of a free operant response in planaria. Science, 139, 1048–1049. Scholar
  55. Marriott, F. H. C. (1958). The absolute light-sensitivity and spectral threshold curve of the aquatic flatworm Dendrocoelum lacteum. Journal of Physiology, 143, 369–379. Scholar
  56. McConnell, J. V. (1962). Memory transfer through cannibalism in planarians. Journal of Neuropsychiatry, 3(1), 542–548.Google Scholar
  57. McConnell, J. V. (1966). Comparative physiology: learning in invertebrates. Annual Review of Physiology, 28, 107–136. Scholar
  58. McConnell, J. V. (Ed.). (1967). A manual of psychological experimentation on planarians (2nd ed.). Ann Arbor, MI: Worm Runner's Digest.Google Scholar
  59. McConnell, J. V., Jacobson, A. L., & Kimble, D. P. (1959). The effects of regeneration upon retention of a conditioned response in the planarian. Journal of Comparative & Physiological Psychology, 52, 1–5. Scholar
  60. Moore, J., & Cooper, J. O. (2003). Some proposed relations among the domains of behavior analysis. The Behavior Analyst, 26, 69–84. Scholar
  61. Morris, E. K. (1992). The aim, progress, and evolution of behavior analysis. The Behavior Analyst, 15, 3–29. Scholar
  62. Neuhof, M., Levin, M., & Rechavi, O. (2016). Vertically- and horizontally-transmitted memories: the fading boundaries between regeneration and inheritance in planaria. Biology Open, 5, 1177–1188. Scholar
  63. Newmark, P. A., & Alvarado, A. S. (2002). Not your father's planarian: a classic model enters the era of functional genomics. Nature Reviews Genetics, 3, 210. Scholar
  64. Nicolas, C. L., Abramson, C. I., & Levin, M. (2008). Analysis of behavior in the planarian model. In R. B. Raffa & S. M. Rawls (Eds.), Planaria: a model for drug action and abuse (pp. 83–94). Austin, TX: Landes Bioscience.Google Scholar
  65. Pagán, O. R. (2014). The first brain: the neuroscience of planarians. New York, NY: Oxford University Press.Google Scholar
  66. Pagán, O. R., Deats, S., Baker, D., Montgomery, E., Wilk, G., Tenaglia, M., & Semon, J. (2013). Planarians require an intact brain to behaviorally react to cocaine, but not to react to nicotine. Neuroscience, 246, 265–270. Scholar
  67. Paskin, T. R., Jellies, J., Bacher, J., & Beane, W. S. (2014). Planarian phototactic assay reveals differential behavioral responses based on wavelength. PLoS One, 9, e114708. Scholar
  68. Pear, J. J., & Eldridge, G. D. (1984). The operant-respondent distinction: future directions. Journal of the Experimental Analysis of Behavior, 42, 453–467. Scholar
  69. Pirenne, M. H., & Marriott, F. H. C. (1955). Light sensitivity of the aquatic flatworm Dendrocoelum lacteum. Nature, 175, 642. Scholar
  70. Poling, A. (2010). Looking to the future: will behavior analysis survive and prosper? The Behavior Analyst, 33, 7–17. Scholar
  71. Raffa, R. B., Holland, L. J., & Schulingkamp, R. J. (2001). Quantitative assessment of dopamine D2 antagonist activity using invertebrate (Planaria) locomotion as a functional endpoint. Journal of Pharmacological and Toxicological Methods, 45(3), 223–226.Google Scholar
  72. Raffa, R. B., Shah, S., Tallarida, C. S., & Rawls, S. M. (2013). Amphetamine conditioned place preference in planarians. Journal of Behavioral & Brain Science, 3, 131–136. Scholar
  73. Ramm, S. A. (2016). Exploring the sexual diversity of flatworms: ecology, evolution, and the molecular biology of reproduction. Molecular Reproduction & Development, 84(2), 120–131. Scholar
  74. Ramoz, L., Lodi, S., Bhatt, P., Reitz, A. B., Tallarida, C., Tallarida, R. J., et al. (2012). Mephedrone (“bath salt”) pharmacology: insights from invertebrates. Neuroscience, 208, 79–84. Scholar
  75. Reddien, P. W., & Alvarado, A. S. (2004). Fundamentals of planarian regeneration. Annual Review of Cell and Developmental Biology, 20, 725–757. Scholar
  76. Reynierse, J. H. (1967). Aggregation formation in planaria, Phagocata gracilis and Cura foremani: species differentiation. Animal Behaviour, 15, 270–272. Scholar
  77. Reynierse, J. H., & Ellis, R. R. (1967). Aggregation formation in three species of planaria: distance to nearest neighbour. Nature, 214, 895–896. Scholar
  78. Reynierse, J. H., Gleason, K. K., & Ottemann, R. (1969). Mechanisms producing aggregations in planaria. Animal Behaviour, 17, 47–63. Scholar
  79. Reynoldson, T. B., & Young, J. O. (1963). The food of four species of lake-dwelling triclads. Journal of Animal Ecology, 32, 175–191. Scholar
  80. Riccio, D., & Corning, W. C. (1969). Slime and planarian behavior. The Psychological Record, 19, 507–513. Scholar
  81. Rilling, M. (1996). The mystery of the vanished citations: James McConnell’s forgotten 1960s quest for planarian learning, a biochemical engram, and celebrity. American Psychologist, 51, 589–598. Scholar
  82. Sahu, S., Dattani, A., & Aboobaker, A. A. (2017). Secrets from immortal worms: what can we learn about biological ageing from the planarian model system? Seminars in Cell & Developmental Biology, 70, 108–121. Scholar
  83. Shomrat, T., & Levin, M. (2013). An automated training paradigm reveals long-term memory in planarians and its persistence through head regeneration. Journal of Experimental Biology, 216, 3799–3810. Scholar
  84. Sidman, M. (1960). Tactics of scientific research. New York, NY: Basic Books.Google Scholar
  85. Singer, M. (1952). The influence of the nerve in regeneration of the amphibian extremity. Quarterly Review of Biology, 27, 169–200. Scholar
  86. Skinner, B. F. (1956). A case history in scientific method. American Psychologist, 11(5), 221. Scholar
  87. Skinner, B. F. (1966). The phylogeny and ontogeny of behavior. Science, 153, 1205–1213.Google Scholar
  88. Smalheiser, N. R., Manev, H., & Costa, E. (2001). RNAi and brain function: was McConnell on the right track? Trends in Neurosciences, 24, 216–218. Scholar
  89. Sokolowski, M. B. C., Disma, G., & Abramson, C. I. (2010). A paradigm for operant conditioning of blow flies (Phorma terrae novae robineau-desvoidy, 1830). Journal of the Experimental Analysis of Behavior, 93, 81–89. Scholar
  90. Stein, L. (1997). Biological substrates of operant conditioning and the operant-respondent distinction. Journal of the Experimental Analysis of Behavior, 67, 246–253. Scholar
  91. Stevenson, C. G., & Beane, W. S. (2010). A low percent ethanol method for immobilizing planarians. PLoS One, 5, 1–12. Scholar
  92. Talbot, J., & Schötz, E. M. (2011). Quantitative characterization of planarian wild-type behavior as a platform for screening locomotion phenotypes. Journal of Experimental Biology, 214, 1063–1067. Scholar
  93. Taliaferro, W. H. (1920). Reactions to light in Planaria maculata, with special reference to the function and structure of the eyes. Journal of Experimental Zoology, 31, 58–116. Scholar
  94. Thompson, R., & McConnell, J. V. (1955). Classical conditioning in planarian, Dugesia dorotocephala. Journal of Comparative and Physiological Psychology, 48, 65–68. Scholar
  95. Travis, G. D. (1981). Replicating replication? Aspects of the social construction of learning in planarian worms. Social Studies of Science, 11, 11–32. Scholar
  96. Vandeventer, J. M., & Ratner, S. C. (1964). Variables affecting the frequency of response of planaria to light. Journal of Comparative & Physiological Psychology, 57, 407–411. Scholar
  97. Walker, D. R. (1966). Memory transfer in planarians: an artifact of the experimental variables. Psychonomic Science, 5, 357–358. Scholar
  98. Walker, D. R., & Milton, G. A. (1966). Memory transfer vs. sensitization in cannibal planarians. Psychonomic Science, 5, 293–294. Scholar
  99. Weeks, S. R., Anderson-Barnes, V. C., & Tsao, J. W. (2010). Phantom limb pain: theories and therapies. The Neurologist, 16, 277–286. Scholar
  100. Wells, P. H. (1967). Training flatworms in a Van Oye maze. In W. C. Corning & S. C. Ratner (Eds.), Chemistry of learning (pp. 251–254). New York, NY: Plenum Press.Google Scholar
  101. Wells, P. H., Jennings, L. B., & Davis, M. (1966). Conditioning planarian worms in a van Oye type maze. American Zoologist, 6(3), 295.Google Scholar
  102. Zimmermann, Z., Watkins, E., & Poling, A. (2015). JEAB research over time: species used, experimental designs, statistical analyses, and sex of subjects. The Behavior Analyst, 38, 203–218. Scholar

Copyright information

© Association for Behavior Analysis International 2018

Authors and Affiliations

  1. 1.Health and Human Services DepartmentUniversity of CincinnatiCincinnatiUSA
  2. 2.Department of PsychologyRider UniversityLawrencevilleUSA
  3. 3.CincinnatiUSA

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