When sounds look right and images sound correct: cross-modal coherence enhances claims of pattern presence

How do people decide whether a stimulus contains a pattern? One possibility is that they rely on a global, non-specific signal of coherence. Interestingly, this signal might reflect a combination of different stimulus sources. Consequently, the coherence of one stimulus might influence decisions about coherence of a second, unrelated stimulus. We explored this possibility in three experiments in which participants judged the presence of a pattern in targets from one sensory modality, while being exposed in the background to incidental coherent and incoherent stimuli in a different modality (visual→auditory, auditory→visual). Across all three experiments, using a variety of judgments, coherence of incidental background cross-modal patterns enhanced claims of pattern presence. These findings advance our understanding of how people judge order in the structured as well as in the unstructured world.