Auditory and visual stimuli as reinforcers among lovebirds ( Agapornis roseicollis)

Abstract

Two groups of Agapornis roseicollis were submitted to an operant conditioning paradigm. The operant response was perching which resulted in either visual stimulus or auditory stimulus or both simultaneously. The visual stimulus consisted of the image of the subject in a one-way mirror, the auditory stimulus of a vocal contact with another lovebird. The presentation of visual stimulus led to a significant increase in the mean perching time on the reinforced perch. This stimulus was thus a highly positive reinforcer, and its positive value was increased even more by the simultaneous presentation of the auditory stimulus. By contrast, partner's vocalizations, given as a reinforcer, induced no increase in perching time on the reinforced perch. Another group was submitted to two experiments to test the reinforcing value of contact calls only. In one experiment, the operant response triggered the repetitive emission of recorded contact calls; in the other, it stopped the continuous and repetitive emission of the calls. Results showed that in this situation birds suppressed the sound of contact calls. These results are discussed in terms of the relationship between visual and auditory stimuli in social communication among these birds.