HUMAN ANALOG TESTS OF THE 6TH STAGE OF OBJECT PERMANENCE

Two adult cats were tested on multiple invisible displacement. A dowel was established as a secondary reinforcer and hidden in a manner simi lar to that used to assess the culmination of sensorimotor intelligenc e in human infants. Three other cats were tested on single invisible d isplacement, a simpler version of the task. For human infants, this ta sk is used to assess the beginning of mental representation in the six th and last stage of sensorimotor intelligence. The cats' searches on these tasks were consistent with representation of an unsensed object and fully developed sensorimotor intelligence.