Single-modality memory mixing in temporal generalization: An effect due to instructional ambiguity.

Two experiments investigated the effect of encoding two standard intervals on
the performance in a temporal generalization task. Previous research has
suggested that when individuals compare current time intervals with a standard
encoded within both the auditory and the visual modality, they apparently use
both the auditorily and the visually encoded standard for comparison so that
each interval was compared with a “mixture” of both standard representations.
However, the results of this study showed that memory mixing also happened
within a pure visual modality. Moreover, it could be shown that the occurrence of
memory mixing depended on instructional ambiguity. If in the training phase
both standard durations were erroneously declared to be the same, memory
mixing did occur in the testing phase. If, however, both standard durations were
described as being different, memory mixing was not observed.