Location memory in the real world: category adjustment effects in 3-dimensional space

The ability to remember spatial locations is critical to human functioning, both in an evolutionary and in an everyday sense. Yet spatial memories and judgments often show systematic errors and biases. Bias has been explained by models such as the Category Adjustment model (CAM), in which fine-grained and categorical information about locations are combined in a Bayesian manner (Huttenlocher, Hedges, & Duncan, 1991). However, experiments testing this model have largely used locations contained in simple geometric shapes and, more recently, 2D scenes. Do the results generalize to location memory in the complex natural world, as they should if the CAM is to provide an over-arching framework for thinking about spatial memory? Here, this issue is addressed using a novel extension of the location memory paradigm that allows for testing of location memory in an everyday, 3D environment. The results support two predictions of the CAM: that memory for locations is biased toward central values, and that the magnitude of error increases with the retention interval.