Incentive Contrast in Domestic Dogs (Canis familiaris)

BENTOSELA, M.; JAKOVCEVIC, A.; ELGIER, A,M.; MUSTACA, A. E.; PAPINI, M. R.

Journal of Comparative Psychology

American Psychological Association

Año: 2009 vol. 123 p. 125 - 130

0735-7036

Dogs trained to receive a preferred food (dry beef liver) from an experimenter learned to maintain a longer gaze on the experimenter than dogs receiving a less preferred food (dog pellets). Dogs downshifted from dry liver to pellets rejected food more frequently than nonshifted controls. Gaze duration also decreased in downshifted dogs below the level of a group always reinforced with pellets. In addition, downshifted dogs tended to move away from the experimenter, adopted a lying down posture. This phenomenon, called successive negative contrast, has been described in analogous experiments with a variety mammalian species, but has failed to occur in similar experiments with nonmammalian vertebrates. Unlike similar previous observations, the present data were obtained in an environment involving interspecific communication.