Common toads (Bufo arenarum) learn to anticipate and avoid hypertonic saline solutions
Publication Type: |
Journal Article |
Year of Publication: |
2007 |
Authors: |
M. Florencia Daneri, Mauricio R. Papini, Rubén N. Muzio |
Publication/Journal: |
Journal of Comparative Psychology |
Keywords: |
anticipation, avoidance, bufo arenarum, conditioning, learning, toads |
ISBN: |
1939-2087 0735-7036 |
Abstract:
Toads (Bufo arenarum) were exposed to pairings between immersion in a neutral saline solution (i.e., one that caused no significant variation in fluid balance), followed by immersion in a highly hypertonic saline solution (i.e., one that caused water loss). In Experiment 1, solutions were presented in a Pavlovian conditioning arrangement. A group receiving a single neutral-highly hypertonic pairing per day exhibited a greater conditioned increase in heart rate than groups receiving either the same solutions in an explicitly unpaired fashion, or just the neutral solution. Paired toads also showed a greater ability to compensate for water loss across trials than that of the explicitly unpaired group. Using the same reinforcers and a similar apparatus, Experiment 2 demonstrated that toads learn a one-way avoidance response motivated by immersion in the highly hypertonic solution. Cardiac and avoidance conditioning are elements of an adaptive system for confronting aversive situations involving loss of water balance.