When given choice, dogs much prefer praise from their owners over food, a new study suggests. The study is one of the first to combine brain imaging data with behavioral experiments to explore dogs' reward preferences.
For the current experiment, the researchers started training the dogs to associate three different objects with different outcomes. A pink toy truck with a food reward; a blue toy knight with verbal praise from the owner; and a no-reward hairbrush to serve as a control.
The dogs were then tested on the three objects while inside an MRI machine. Each dog underwent 32 trials for each of the three objects while recording their neural activity.
All dogs showed stronger neural activation to the reward stimuli compared to the stimulus that signaled no reward. Four of the dogs showed particularly strong activation of the stimulus signaling praise from their owners. Nine of the dogs showed similar neural activation for both the praise stimulus and the eating stimulus. And two dogs consistently showed more activation as shown food stimulus.