Anticipatory tachycardiac response and avoidance behavior in an aversive conditioning situation in the toad Bufo arenarum.

DANERI, M.F.; MUZIO, R.N.

Oviedo

Congreso; 12th Biennial Meeting of the International Society for Comparative Psychology. 16th Congress of the Spanish Society for Comparative Psychology; 2004

International Society for Comparative Psychology

The object of this work is to establish the relation between changes in behavior and cardiovascular adjustment, specially to describe the cardiovascular response during  classical aversive conditioning in the amphibian Bufo arenarum.  A paradigm with a 300 mM NaCl solution as conditioned stimulus (CS) and an aversive solution (800 mM NaCl) as unconditioned stimulus (US) was tested in male toads. There were two separated analysis: a behavioral test and a cardiovascular test. In the first, animals displayed escape behavior on the first session, followed by an avoidance behavior during the following sessions, evidence of the  conditioning of the avoidance response.  On the other hand, the cardiovascular test showed that a cardiovascular reactivity exists in response to changes in the environment, and that this cardioaccelerated response is according to metabolic demands of the somatomotor response to aversive stimulation (escape behavior). Furthermore, these results suggest a conditioning of the cardioaccelerative response. An increased heart rate was observed during the last period of the CS presentation, showing that this stimulus acts as a cue predicting the aversive US.   Cardiovascular conditioning in this species is probably an adaptative response (modulated by a cognitive process) developed to prepare to confront a repetitive aversive situation an allow a potential avoidance response.