Geometric Complexity and Object Search in Infancy

In four experiments we investigated the role of geometric path type in infants' ability to make spatial inferences about the location of a hidden object after they themselves had been moved through space. Nine-month-old infants were moved along geometrically simple paths of rotation (Experiments 1 and 2) or translation (Experiment 3) or along geometrically complex paths of combined rotation and translation (Experiment 4). In all but the fourth experiment, infants were able to retrieve an object hidden before they were moved, as long as the object was not located behind them at test time. Direct comparisons among the conditions showed that moving infants along geometrically simple paths led to significantly better performance than moving them along geometrically complex paths. We found the length of a path, the time needed to traverse it, and the likelihood of fixation of the target to be unrelated to the infants' performance. These findings are discussed in the context of theories of the development of spatial knowledge.