Effects of intrastimulus modality change on audiovisual time-to-arrival judgments.

In this research, anticipatory perception of an approaching vehicle was examined. By varying the availability of visual and acoustic media, conditions occurred in which the input to the modalities was repetitively interrupted while the presentation of the approach event continued. In these conditions, the audio and the visual signals were presented either in short and concurrent segments at regular intervals or in alternation (interleaved) at regular intervals. It was found that interrupting the signal within a single modality did not affect performance if the approach information was available in the alternate modality. These results are consistent with a modally flexible detection mechanism for the perception of approaching objects. This modal flexibility may provide some evidence that information is detected using a modality-neutral strategy.