The use of perspective as a depth cue with a 2D display in 4 and 5-month-old infants.

Four experiments were conducted to study the use of perspective as a depth cue in infants, using an eye-tracking-system. In the first experiment, no significant difference was observed between the looks for the "normal" and the "strange" events on the complete display and at the target in 4-month-olds. In the second experiment, the results of 5-month-olds were similar to those obtained by 4-month-olds but they looked more at the test events when the "strange" event was presented first. In the third experiment, 5 month-olds were shown a repeated presentation adapted from the "Partial-Lag" design. Infants' exploration of the target indicated that they looked more at the "strange" event than at the "normal" event. In the fourth experiment, the same design was used with 4-month-olds but no difference between conditions was observed. Five-month-olds seem to be able to use the perspective cues alone. These different data are discussed.