Role of spatial contiguity in sensory preconditioning with humans

The present study demonstrates the contribution of spatial contiguity in the formation of associations between two neutral stimuli. Using human participants, we used visual conditioned stimuli (CSs) in a sensory preconditioning design in which simultaneous CS2-CS1 pairings and CS4-CS3 pairings were interspersed during Phase 1, followed by sequential CS1-US+ (i.e., CS1-pleasant US) and CS3-US-^- (i.e., CS3-unpleasant US) pairings during Phase 2. The conditioned response was a shift in the gaze of the participants to the location where the US+ (i.e., short video clip) appeared. Distances between CS2 and CS1 and between CS4 and CS3 were manipulated. Our results showed a greater response to CS2 when the Phase 1 stimuli were adjacent rather than separated by 100 pixels. Implications for the role of spatial contiguity in associative learning are discussed.