Associative Basis of Landmark Learning and Integration in Vertebrates.

Early work on spatial navigation evaluated what stimuli (kinesthetic or extra-maze) support small-scale navigation and the nature of the underlying learning (place versus response) process. Contemporary research has focused primarily on how cues interact to determine spatial search. This review covers three general findings from research on landmark-based spatial search in vertebrates. First, pigeons and rats encode simple spatial maps in both open-field and touchscreen environments. Second, a nascent literature shows how simple maps can be integrated into complex maps through higher-order associative processes. The spatial-integration hypothesis provides an associative mechanism for spatial mapping that serves as an alternative to a previously posed configural mechanism. Finally, the evidence for associative cue-competition phenomena in landmark learning is reviewed-focusing on blocking and overshadowing. These findings support a role for associative learning in spatial tasks and provide a powerful explanatory framework for understanding cue integration and competition effects in landmark learning.