Table 2.

Treatments used in experiment 2 that were designed to induce different emotions.

Treatment	Emotion (arousal/valence)	Description of the treatment	Duration
Initial access to interaction	High arousal positive	The experimenter played and interacted with the dog	60 s
Prolonged access to interaction	Low arousal positive	Experimenter petted the dog (voluntary) until the dog relaxed (head down on floor/paws without movement, eyes open or closed) or lost interest and walked away	15–40 min
Inaccessible play	High arousal negative	The test dog is alone in the testing area. The experimenter played with a pen mate on the other side of the fence in front of the test dog, and invited the test dog to come to play by calling it and making eye contact with it. However, the dog was unable to cross the fence and join the play session	60 s
No play	Low arousal negative	The experimenter initiated play for 10 s, then stopped, crossed her arms, stood still and ignored the dog. The experimenter waited until the dog stopped interacting, and then tested after 30 s	40–60 s