Abstract
To investigate the role of attention in the time course of visual working memory, a memory scanning experiment was conducted with three conditions: control, neutral cue and spatial cue. On each trial, a memory array of 4 items (simple geometric shapes) preceded a probe item at varying inter-stimulus intervals (ISIs). In cued conditions, either a neutral or informative spatial cue was presented 300 ms before the probe onset. The neutral cue pointed toward all four locations of the memory array, whereas the spatial cue pointed in the direction of one of the 4 array items, either matching or mismatching the probe. In all conditions, observers reported whether or not the probe differed from an item in the memory array. Response reaction times were collected, and comparison effects (CEs) were computed by subtracting average reactions times for matched from mismatched memory array-probe pairings. Similar to previous findings (Jacob, Breitmeyer & Treviño, 2013), CEs in the control condition varied systematically across ISIs, likely reflecting fluctuations in attention and working memory content. The CEs in the spatially-cued condition followed the same temporal pattern as the control condition, but the amplitude of the fluctuations was dampened, and the CEs diminished by 4000 ms. As expected, the spatial cue utilizes spatial attention to make a judgement between the cued item and the probe, reducing the amount of information that needs to be maintained in memory. This is likely to reflect spatial attention overriding the effects of attention to WM content. In contrast, the CEs in the neutral-cued condition showed CE fluctuations with higher amplitude for later ISIs. The neutral cue enhances processing of the content of working memory, amplifying CEs as ISIs increase. Our results suggest that attention plays a role in determining stages of information processing in working memory.
Meeting abstract presented at VSS 2016