An inability to set independent attentional control settings by hemifield

Abstract

Recent evidence suggests that people can simultaneously activate attentional control setting for two distinct colors. However, it is unclear whether both attentional control settings must operate globally across the visual field or whether each can be constrained to a particular spatial location. Using two different paradigms, we investigated participants' ability to apply independent color attentional control settings to distinct regions of space. In both experiments, participants were told to identify red letters in one hemifield and green letters in the opposite hemifield. Additionally, some trials used a "relevant distractor"-a letter that matched the opposite side's target color. In Experiment 1, eight letters appeared (four per hemifield) simultaneously for a brief amount of time and then were masked. Relevant distractors increased the error rate and resulted in a greater number of distractor intrusions than irrelevant distractors. Similar results were observed in Experiment 2 in which red and green targets were presented in two rapid serial visual presentation streams. Relevant distractors were found to produce an attentional blink similar in magnitude to an actual target. The results of both experiments suggest that letters matching either attentional control setting were selected by attention and were processed as if they were targets, providing strong evidence that both attentional control settings were applied globally, rather than being constrained to a particular location.

Limits in feature-based attention to multiple colors

“…These results are consistent with ours where we found an elevated detection threshold for the two-cue than the one-cue condition. However, we also noted several studies, in particular ones employing the attentional capture paradigm (Folk et al, 1992), that reported that attention can be captured when searching for two target colors, suggesting that attentional templates can contain two colors (Adamo, Pun, Pratt, & Ferber, 2008; Becker et al, 2015; Irons et al, 2012; Moore & Weissman, 2010, see also Beck et al, 2012). Our results of a significant cueing effect for two cues relative to baseline can be consistent with these studies.…”

“…These results thus suggest that the number of active attentional templates is severely limited (possibly limited to one). However, other studies have found evidence that there could be multiple (at least two) active attentional templates (Adamo, Pun, & Ferber, 2010; Beck, Hollingworth, & Luck, 2012; Becker, Ravizza, & Peltier, 2015; Irons, Folk, & Remington, 2012; Moore & Weissman, 2010). No apparent consensus has emerged from these studies, likely due to the complex nature of the visual search task.…”

Multiple Attentional Sets While Monitoring Rapid Serial Visual Presentations

“…On the one hand, as shown by Adamo and colleagues (Adamo et al, 2008(Adamo et al, , 2010, there is evidence that observers are able to establish two attentional sets. On the other hand, Becker et al (2015) demonstrated that attentional sets were applied globally to the visual field, rather than being confined to specific spatial locations.…”

“…This failure is due to the following: First, relevant distractors that shared the same features as targets occurred in the same potential locations as the true targets in these studies; hence it is plausible that the distractors captured attention as a result of shared sets for location. Second, as claimed by Becker et al (2015), the findings by Adamo and colleagues (Adamo et al, 2008(Adamo et al, , 2010 involved cueing, and therefore did not reflect the ability of the visual system to maintain multiple attentional sets confined to various specific locations. Therefore, it remains unclear whether two attentional sets for different colours at different spatial locations can be established.…”

“…Alternatively, participants may not be able to maintain two different search modes (Becker et al, 2015); observers may fail to maintain separate attentional sets when engaging in a relatively demanding search task. Our results indicate that attentional sets can be split between different visual locations as long as the split involves a single search mode, but that splitting fails across search modes.…”