The lateralized ERP N2pc component has been shown to be an effective marker of attentional object selection when elicited in a visual search task, specifically reflecting the selection of a target item among distractors. Moreover, when targets are known in advance, the visual search process is guided by representations of target features held in working memory at the time of search, thus guiding attention to objects with target-matching features. Previous studies have shown that manipulating working memory availability via concurrent tasks or within task manipulations influences visual search performance and the N2pc. Other studies have indicated that visual (non-spatial) vs. spatial working memory manipulations have differential contributions to visual search. To investigate this the current study assesses participants' visual and spatial working memory ability independent of the visual search task to determine whether such individual differences in working memory affect task performance and the N2pc. Participants ( n = 205) completed a visual search task to elicit the N2pc and separate visual working memory (VWM) and spatial working memory (SPWM) assessments. Greater SPWM, but not VWM, ability is correlated with and predicts higher visual search accuracy and greater N2pc amplitudes. Neither VWM nor SPWM was related to N2pc latency. These results provide additional support to prior behavioral and neural visual search findings that spatial WM availability, whether as an ability of the participant's processing system or based on task demands, plays an important role in efficient visual search.
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Long-term memory and working memory compete and cooperate to guide attention
Multiple types of memory guide attention: Both long-term memory (LTM) and working memory (WM) effectively guide visual search. Furthermore, both types of memories can capture attention automatically, even when detrimental to performance. It is less clear, however, how LTM and WM cooperate or compete to guide attention in the same task. In a series of behavioral experiments, we show that LTM and WM reliably cooperate to guide attention: Visual search is faster when both memories cue attention to the same spatial location (relative to when only one memory can guide attention). LTM and WM competed to guide attention in more limited circumstances: Competition only occurred when these memories were in different dimensions – particularly when participants searched for a shape and held an accessory color in mind. Finally, we found no evidence for asymmetry in either cooperation or competition: There was no evidence that WM helped (or hindered) LTM-guided search more than the other way around. This lack of asymmetry was found despite differences in LTM-guided and WM-guided search overall, and differences in how two LTMs and two WMs compete or cooperate with each other to guide attention. This work suggests that, even if only one memory is currently task-relevant, WM and LTM can cooperate to guide attention; they can also compete when distracting features are salient enough. This work elucidates interactions between WM and LTM during attentional guidance, adding to the literature on costs and benefits to attention from multiple active memories.
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- PAR ID:
- 10377496
- Date Published:
- Journal Name:
- Attention, Perception, & Psychophysics
- ISSN:
- 1943-3921
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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