Discrimination learning and extinction in paramecia (P. caudatum).

Department of Psychology, University of Toledo, Toledo, OH 43606, USA.
Psychological Reports (Impact Factor: 0.44). 07/2006; 98(3):705-11. DOI: 10.2466/pr0.98.3.705-711
Source: PubMed

ABSTRACT Prior attempts to condition a one-celled organism, paramecium, by either classical or instrumental procedures have yielded both positive and negative results. As the results of those studies may be subject to several interpretations other than one indicating learning, it was decided to use a more traditional technique for the present study. This experiment was designed to assess whether aversive electric shock could be used to train paramecia on a brightness discrimination task, a procedure that has been used in animal learning research. The results indicated that such learning may have occurred.

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