Processing of indexical information requires time: Evidence from change deafness

Studies of change detection have increased our understanding of attention, perception, and memory. In two innovative experiments we showed that the change detection phenomenon can be used to examine other areas of cognition—specifically, the processing of linguistic and indexical information in spoken words. One hypothesis suggests that cognitive resources must be used to process indexical information, whereas an alternative suggests that it is processed more slowly than linguistic information. Participants performed a lexical decision task and were asked whether the voice presenting the stimuli changed. Nonwords varying in their likeness to real words were used in the lexical decision task to encourage participants to vary the amount of cognitive resources/processing time. More cognitive resources/processing time are required to make a lexical decision with word-like nonwords. Participants who heard word-like nonwords were more likely to detect the change when it occurred (Experiment 1) and were more confident that the voice was the same when it did not change (Experiment 2). These results suggest that indexical information is processed more slowly than linguistic information and demonstrate how change detection can provide insight to other areas of cognition.