The architecture of interaction between visual working memory and visual attention

Abstract

In five experiments, we examined whether a task-irrelevant item in visual working memory (VWM) interacts with perceptual selection when VWM must also be used to maintain a template representation of a search target. This question is critical to distinguishing between competing theories specifying the architecture of interaction between VWM and attention. The single-item template hypothesis (SIT) posits that only a single item in VWM can be maintained in a state that interacts with attention. Thus, the secondary item should be inert with respect to attentional guidance. The multiple-item template hypothesis (MIT) posits that multiple items can be maintained in a state that interacts with attention; thus, both the target representation and the secondary item should be capable of guiding selection. This question has been addressed previously in attention capture studies, but the results have been ambiguous. Here, we modified these earlier paradigms to optimize sensitivity to capture. Capture by a distractor matching the secondary item in VWM was observed consistently across multiple types of search task (abstract arrays and natural scenes), multiple dependent measures (search reaction time (RT) and oculomotor capture), multiple memory dimensions (color and shape), and multiple search stimulus dimensions (color, shape, common objects), providing strong support for the MIT. (PsycINFO Database Record

Figure 1

Sequence of events in a trial and singleton-match manipulation for Experiment 1A. The method in Experiment 1B was identical, except the memory sample and search cue were presented simultaneously.

Figure 2

Mean search RT results as a function of singleton-match condition for Experiments 1A, 1B, 2, and 4. Error bars are condition-specific, within-subject 95% confidence intervals (Morey, 2008).

Figure 3

Sequence of events in a trial and singleton-match manipulation for Experiment 2.

Figure 4

Sequence of events in a trial and match manipulation for Experiment 3.

Figure 5

Results of Experiment 3. A: Overall probability of fixating the critical distractor as a function of match condition. B: Probability of fixating the critical distractor for each ordinal fixation during search (fixation 1 is the first participant-controlled fixation after the first saccade on the scene). C: Cumulative probability of fixating the target object for each ordinal fixation as a function of match condition. Error bars are condition-specific, within-subject 95% confidence intervals (Morey, 2008).

Figure 6

Results of Experiment 4. A: Overall probability of fixating the critical distractor as a function of match condition. B: Probability of fixating the critical distractor for each ordinal fixation during search (fixation 1 is the first participant-controlled fixation after the first saccade on the scene). C: Cumulative probability of fixating the target object for each ordinal fixation as a function of match condition. Error bars are condition-specific, within-subject 95% confidence intervals (Morey, 2008).