Tolerance to delayed reward tasks in social and non-social contexts

Domestic dogs have demonstrated striking social skills towards humans, however, there are few studies investigating impulsivity with delay-choice tasks in communicative contexts. In Study I we introduced a novel social delay-choice task in which subjects had to choose between one human cueing an immediate, low quality reward and another human signaling a delayed, high quality reward. In Study 2 we evaluated the tolerance to increasing delays using social and non-social cues. We also explored if more self-controlled dogs show any distinct behaviours during delays. Finally, we correlated all results with the Dog Impulsivity Assessment Scale (Wright et al., 2011). In Study 1 dogs reached an average maximum delay of 11.55 s. In Study 2 that average was 52.14 s with social cues and 40.2 s with non-social, but differences were not significant. Tolerance to delays showed high interindividual variation. Dogs remained mostly standing and near the delayed experimenter in the social tasks although we could not to find any distinct coping strategies. No significant correlations were found between the delay reached and behaviours, neither with the scale. These results show the relevance of the parameters and methods used to investigate tolerance to delay of reinforcements. More investigations are required, especially an assessment of the same subjects performing the same tasks using different contexts. (C) 2016 Elsevier B.V. All rights reserved.