Decomposing the Garner interference paradigm: evidence for dissociations between macrolevel and microlevel performance.

Three Garner interference experiments are described in which baseline, filtering, and correlated performance were assessed at both a macrolevel (condition average) and microlevel (intertrial contingency), using the pair-wise combinations of auditory pitch, loudness, and location. Discrepancies between pairs of dimensions were revealed between macro- and microlevel estimates of performance and, also, between filtering costs and correlated benefits, relative to baseline. The examination of the intertrial effects associated with filtering costs suggested that effects of increased stimulus uncertainty were mandatory, whereas effects of irrelevant variation were not. The examination of the intertrial effects associated with correlated benefits suggested that the detection of stimulus repetition took precedence over that of stimulus change. Violations of standard horse race accounts of processing did not appear to stem from differences in the absolute or relative speeds of processing between dimensions but, rather, from the special role that certain dimensions (e.g., pitch) may play in certain modalities (e.g., audition). The utility of examining repetition effects is demonstrated by revealing a level of understanding regarding stimulus processing typically hidden by aggregated measures of performance.