Now You See It, Now You Don’t

Abstract

The cognitive ability of dogs can be assessed using tasks from the human developmental literature. A task that appears to have ecological relevance is the object-permanence task, in which performance hinges on understanding that an object continues to exist once it can no longer be seen. Although dogs are good at visible displacement tasks, in which an object disappears into a container, they can also understand an invisible displacement, in which the container holding the object is moved. Furthermore, we have found that dogs are able to show considerable memory for the invisibly displaced object. We have also found evidence for object permanence in dogs using the violation-of-expectancy procedure, in which subjects look longer at a stimulus that violates expectations (a screen that appears to pass through an object that has been placed behind the screen) than one that does not. Similarly, we have found that dogs look longer at an object that appears to have changed color or size after being placed behind a screen compared to an object that has not changed. Object-permanence tasks provide an ecologically relevant means of evaluating the cognitive development of dogs.