MEMORY FOR PICTURES OF UPRIGHT AND INVERTED PRIMATE FACES IN HUMANS (HOMO-SAPIENS), SQUIRREL-MONKEYS (SAIMIRI-SCIUREUS), AND PIGEONS (COLUMBA-LIVIA)

Humans (Home sapiens) and squirrel monkeys (Saimiri sciureus) were tes ted for memory of upright and inverted primate faces. Working memory w as tested in Experiment 1 with a delayed matching-to-sample procedure, and reference memory was examined in Experiment 2 by requiring subjec ts to learn to discriminate between successive pairs of upright or inv erted pictures. Both human and monkey subjects showed better working m emory for upright than for inverted human faces and better reference m emory for upright than for inverted human and great ape faces. In Expe riment 3, reference memory tests with pigeons (Columba livia) showed n o effects of inversion on rate of learning with face pictures. We argu e that these findings cannot be explained easily by an individual prim ate's lifetime experiences with primate faces. We suggest that similar evolved mechanisms for primate face recognition in people and monkeys are responsible for the pattern of data reported.