A novel demonstration of preparation in pop-out search.

There is an ongoing debate among visual attention researchers about whether top-down processes contribute to pop-out search. In the present study, we describe a new method to orthogonally manipulate top-down preparation and feature priming in a pop-out search task. On each trial, participants viewed a single-item (randomly blue or orange) followed by a pop-out search display (randomly blue target with orange distractors, or vice versa). Preparation was induced by instructing participants to respond to the single-item if it was a particular colour and to ignore it otherwise-but to respond to the odd-coloured target in all following pop-out search displays. This method allowed us to examine whether top-down preparation for the single-item influenced subsequent pop-out search. Our results revealed a large effect of preparation for the single-item on subsequent search response times. We discuss this result in relation to the interplay between top-down control and selection history effects in pop-out visual search. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Imagined object files: Visual imagery produces partial repetition costs where perception does not.

The present study explored whether object (or event) files can be formed that integrate color imagery and perceptual location features. To assess this issue, a cue-target procedure was used whereby color imagery was cued to be generated at a particular location in space, which was then followed by a perceptual color discrimination task. Partial repetition costs (PRCs) were then measured by varying the overlap of the color and location features of the cue and target to evaluate whether an object/event file was formed. Robust PRCs were observed when imagery was generated at a location, supporting the idea that imagery and perception can be incorporated into a common event file. It was also revealed that the PRC effects for perceptual color cues were tenuous-they did not reach significance in the present study. Overall, the present study indicates that imagery can produce stronger binding effects than perception, offering important insights into the role that active engagement plays in the formation of object/event files.

Item-specific control of attention capture: An eye movement study.

Measures of attentional capture are sensitive to attentional control settings. Recent research suggests that such control settings can be linked associatively to specific items. Rapid item-specific retrieval of these control settings can then modulate measures of attentional capture. However, the processes that produce this item-specific control of attentional capture are unclear. The current study addressed this issue by examining eye-movement patterns associated with the item-specific proportion congruency effect (ISPC). Participants searched for a shape singleton target in search displays that also contained a colour singleton-the colour singleton was either the same item as the shape singleton (congruent trials) or a different item (incongruent trials). The relative proportions of congruent and incongruent trials were manipulated separately for two distinct item types that were randomly intermixed. Response times (RTs) were faster on congruent than incongruent trials, and this congruency effect was larger for high-proportion congruent (HPC) than low-proportion congruent (LPC) items. Eye movement data revealed a higher proportion of saccades towards the distractor and longer dwell times on the distractor in the HPC condition. These results suggest that item-specific associative learning can influence the strength of representation of the task goal (e.g., find the odd shape), a form of selection history effect in visual search.

Top-down then automatic: Instructions can continue to influence visual search when no longer actively implemented.

The present study investigated the automaticity of top-down instructions in visual search when the instruction was no longer actively implemented. To do so, we exploited the Priming of Pop-out (PoP) effect, a selection history phenomenon that reflects faster responses when the target and distractor colors are repeated than switched across trials of singleton search. We then had participants perform a color singleton search task where they implemented the instruction of imagining the opposite color of the previous target, which put the target colors underlying PoP and the imagery instruction in opposition. To assess automaticity, on some trials participants were instructed to stop implementing the imagery instruction. When the imagery instruction was implemented, responses were faster when the target and distractor colors switched (i.e., imagery congruent) than repeated (i.e., imagery incongruent) across search displays - a pattern of results opposite to the PoP effect. When participants were to not implement this instruction, the PoP effect was absent, indicating the imagery instruction had a lingering influence on visual search. This remained true even when participants reported successfully not implementing the instruction, and only when the imagery abandonment instruction was supplanted by a different top-down task was the lingering influence removed such that the PoP effect returned. Overall, the present study demonstrates that top-down instructions can continue to influence visual search despite the will of the observer.

The attentional boost effect and perceptual degradation: Assessing the influence of attention on recognition memory.

Researchers have suggested that the recognition memory effects resulting from two separate attentional manipulations-attentional boost and perceptual degradation-may share a common cause; namely a transient up-regulation of attention at the time of encoding that leads to enhanced memory performance at the time of retrieval. Prior research has demonstrated that inducing two similar transient shifts of attention simultaneously produces redundant performance in memory. In the present study, we sought to evaluate the combined influence of the attentional boost and perceptual degradation on recognition memory. If these two effects share a common cause, then we ought to observe a redundancy in memory performance, such that these two factors interact. Yet, across four experiments we fail to observe such a redundancy in recognition memory. We evaluate these results using the limited resource model of attention and speculate on how combining transient shifts of attention may produce redundant memory performance in the one case, but non-redundant performance in the other case.

It hurts more than it helps: Cuing T1 with imagery can impair T2 identification in an attentional blink task.

The purpose of the present study was to evaluate whether cuing a first target with color imagery could influence second target identification using the two-target attentional blink procedure of MacLellan, Shore, and Milliken (2015, Psychological Research, 79, 556-569.). This method asks participants to identify a first target word interleaved with a distractor word and a second target word that follows the first target after a variable stimulus onset asynchrony. Prior to each trial of the two-target procedure, participants were cued to generate color imagery that was congruent with the color of the first target word, the color of the distractor word, the color of neither the first target or distractor words (Experiment 2), or to withhold generating color imagery (Experiment 3). The results revealed that identification of the second target was impaired when the cue was congruent with the distractor word, and equivalent when the cue was congruent with the first target word, relative to when color imagery was withheld. These results suggest that the attentional resources needed to identify the first target were not reduced by a match between the color of imagery and the first target, but a match between the color of imagery and the distractor increased the attentional resources needed to identify the first target.

Comparing imagery and perception: Using eye movements to dissociate mechanisms in search.

It has been demonstrated that color imagery can have a profound impact when generated prior to search, while at the same time, perceptual cues have a somewhat limited influence. Given this discrepancy, the present study evaluated the processes impacted by imagery and perception using a singleton search task where participants had to find an oddball colored target among homogenously colored distractors. Prior to each trial, a perceptual color was displayed or imagery was generated that could match the target, distractors, or neither item in the search array. It was revealed that color imagery led to both a larger benefit when it matched the target and a larger cost when it matched the distractors relative to perceptual cues. By parsing response times into pre-search, search, and response phases based on eye movements, it was revealed that, while imagery and perceptual cues both influenced the search phase, imagery had a significantly greater influence than perceptual cues. Further, imagery influenced pre-search and response phases as well. Overall, the present findings reveal that the influence of imagery is profound as it affects multiple processes in the vision-perception pipeline, while perception only appeared to impact search.

Top-down imagery overrides the influence of selection history effects.

The present study investigated whether color imagery could override the representations of the prevalent selection history effect termed Priming of Pop-out (PoP), which is constituted by faster responding when the target color is repeated rather than switched across trials of color singleton search. Participants imagined a color in the interval between trials of a color singleton search task that could be the same as or different to the previous target color, and they were to rate the vividness of these representations following each imagery event. It was revealed that when highly vivid imagery was reported, the PoP effect was attenuated relative to less vivid forms of it (and absent in two out of three experiments), and that color imagery eliminated the build-up of priming following consecutive target color repeats. Overall, the present findings suggest the representations of the selection history system can be overridden by top-down imagery.

Looking into the mind's eye: Directed and evaluated imagery vividness modulates imagery-perception congruency effects.

While most people have had the experience of seeing a representation in the mind's eye, it is an open question whether we have control over the vividness of these representations. The present study explored this issue by using an imagery-perception interface whereby color imagery was used to prime congruent color targets in visual search. In Experiments 1a and 1b, participants were required to report the vividness of an imagined representation after generating it, and in Experiment 2, participants were directed to create an imagined representation with particular vividness prior to generating it. The analyses revealed that the magnitude of the imagery congruency effect increased with both reported and directed vividness. The findings here strongly support the notion that participants have metacognitive awareness of the mind's eye and willful control over the vividness of its representations.

Visual imagery influences attentional guidance during visual search: Behavioral and electrophysiological evidence.

Recent behavioral studies have shown that color imagery can benefit visual search when it is congruent with an upcoming target. In the present study we investigated whether this color imagery benefit was due to the processes underlying attentional guidance, as indicated by the electrophysiological marker known as the N2pc component. Participants were instructed to imagine a color prior to each trial of a singleton search task. On some trials, the imagined color was congruent with the target, and on other trials, it was congruent with the distractors. The analyses revealed that the N2pc was present when color imagery was congruent with the search target, and absent when it was congruent with the distractors. Further, there was preliminary evidence that attentional guidance depended on the vividness of color imagery and the frequency at which participants implemented the imagery instruction. Overall, the results of the present study indicate that color imagery can influence the attentional guidance processes underlying visual search.

Learning of association between a context and multiple possible target locations in a contextual cueing paradigm.

Searching for a target is faster in a repeated context compared to a new context, possibly because the learned contextual information guides visual attention to the target location (attentional guidance). Previous studies showed that switching the target location following learning, or having the target appear in one of multiple possible locations during learning, fails to produce search facilitation in repeated contexts. In this study, we re-examined whether the learning of an association between a distractor configuration context and a target is limited to one-to-one context-target associations. Visual search response times were facilitated even when a repeated context was associated with one of four possible target locations, provided the target locations were also shared by other repeated distractor contexts. These results suggest that contextual cueing may involve mechanisms other than attentional guidance by one-to-one context-target associations.

Selective attention effects on recognition: the roles of list context and perceptual difficulty.

Two recent studies reported superior recognition memory for items that were incongruent targets than for items that were congruent targets in a prior incidental study phase (Krebs et al. in Cereb Cortex (New York, NY) 25(3):833-843, 2015; Rosner et al. in Psychol Res 79(3):411-424, 2015). The present study examined this effect further by addressing two issues. First, we examined whether this effect is sensitive to the list context in which congruent and incongruent items are presented. In Experiment 1, this issue was addressed by manipulating the relative proportions of congruent and incongruent trials in the study phase. In Experiments 2A and 2B, the same issue was examined by contrasting randomly intermixed and blocked manipulations of congruency. The results of these experiments, as well as a trial-to-trial sequence analysis, demonstrate that the recognition advantage for incongruent over congruent items is robust and remarkably insensitive to list context. Second, we examined recognition of incongruent and congruent items relative to a single word baseline condition. Incongruent (Experiment 3A) and congruent (Experiment 3B) items were both better recognized than single word items, though this effect was substantially stronger for incongruent items. These results suggest that perceptual processing difficulty, rather than interference caused by different target and distractor identities on its own, contributes to the enhanced recognition of incongruent items. Together, the results demonstrate that processes that are sensitive to perceptual processing difficulty of items but largely insensitive to list context produce heightened recognition sensitivity for incongruent targets.

Coordinating the interaction between past and present: Visual working memory for feature bindings overwritten by subsequent action to matching features.

The object-file framework forwarded by Kaheman, Treisman, and Gibbs (1992) has been enormously influential in our understanding of how the visual system links together prior visual content with a current input. Although this framework was initially developed to account for the perceptual benefits associated with feature conjunction repetitions, the present series of experiments examines how the core processes of this framework may also help explain behavior in tasks that require explicit remembering of visual information over the short term. Building off our previous work (Fiacconi & Milliken, 2012, 2013), here we introduce a procedure that affords the opportunity to examine the contributions of object-file review processes to both speeded performance and visual short-term memory (VWM) within the same task. Across two experiments we demonstrate a novel coupling between memory accuracy and speeded performance, such that the conditions that promote faster performance also tend to produce better memory, and vice versa. These findings are discussed in relation to the object-file framework and suggest that the object-file review processes known to guide behavior in speeded performance tasks may also have important mnemonic consequences. Together, these findings unite two lines of research to which Anne Treisman made indelible contributions.

The representational basis of positive and negative repetition effects.

Repetition of target features in the same spatial location can either benefit or impair performance in perceptual tasks. Moreover, which of these two effects occurs can depend on whether an intervening event is presented temporally between consecutive targets. Here, we explored these effects for color feature repetitions by varying the representational overlap of consecutive targets. The second target on all experimental trials was a simple perceptual color. The task and first target were manipulated to vary the representation produced in response to the first target (perceptual representation of color in Experiment 1; imagined representation of color in Experiments 2 and 5; conceptual representation of color in Experiment 3; color-unrelated representation in Experiment 4). Perceptual and imagined color representations for the first target produced a positive repetition effect when an intervening event did not appear between targets but produced a negative repetition effect when an intervening event did appear between targets. In contrast, conceptual color and color-unrelated representations produced a negative repetition effect both with and without an intervening event. These results suggest that positive repetition effects depend on consecutive targets that share visual representations, whereas negative repetition effects reflect a more complex relationship between stimulus and response features across targets. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

The repetition decrement effect in recognition memory: The influence of prime-target spacing.

Rosner, Lopez-Benitez, D'Angelo, Thomson, and Milliken (2018, see also Collins, Rosner & Milliken, 2018) reported a novel recognition memory effect. In an incidental study phase, participants saw prime-target word pairs and were asked to name aloud just the target. Primes were unmasked, but participants were not required to attend to them. On repeated trials the prime and target were the same word, whereas on not-repeated trials the prime and target were different words. In the following test phase, recognition memory was better for not-repeated targets than for repeated targets. The present study explores whether this effect is influenced by the spacing between primes and targets. The results replicated prior studies in that immediate repetition resulted in a repetition decrement effect, but spaced repetition (by about 10 min) resulted in the opposite effect - better recognition for repeated than not-repeated targets. The results are discussed in relation to deficient processing theories of the spacing effect.

Imagined event files: An interplay between imagined and perceived objects.

An important function of attention is to integrate features processed in distinct brain areas into a single coherent object representation. The immediate outcome of this binding process has been termed an event file, a transient memory structure that links features, context, and associated actions. A key result that supports the existence of event files is the partial repetition cost - slowed responses to a current event thought to reflect the updating of event file bindings in simple trial-to-trial repetition methods. In four experiments, using a procedure similar to Hommel (Visual Cognition, 5 (1/2), 183-216, 1998), we explored whether similar event file binding effects occurred when participants imagine rather than perceive a first event prior to responding to a following visual event. The results indicate that this effect does occur, implying that feature binding in imagery and perception may follow similar principles.

Cueing color imagery: A critical analysis of imagery-perception congruency effects.

The relation between mental imagery and visual perception is a long debated topic in experimental psychology. In a recent study, Wantz, Borst, Mast, and Lobmaier (2015) demonstrated that color imagery could benefit color perception in a task that involved generating imagery in response to a cue prior to a forced-choice color discrimination task. Here, we scrutinized whether the method of Wantz et al. warrants strong inferences about the role of color imagery in color perception. In Experiments 1-3, we demonstrate that the imagery effect reported by Wantz et al. does replicate nicely using their method but does not occur when cue-target contingencies and a redundancy between the imagery and response dimensions are removed from their method. In Experiments 4-6, we explored cued imagery effects further using a method in which the cued imagery dimension was orthogonal to the response dimension. The results of these experiments demonstrate that a compelling endogenously cued imagery effect does not occur for lone targets but does occur for singleton color targets embedded amid homogenous color distractors. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Strategic visual imagery and automatic priming effects in pop-out visual search.

Priming of Pop-out (PoP) is defined by faster responses in singleton search when the target repeats across trials than when it switches. In a recent study, it was shown that the PoP effect can be reversed using visual imagery (Cochrane, Nwabuike, Thomson, & Milliken, 2018). The goal of the current study was to pinpoint the procedural constraints necessary to observe the imagery-induced reversal of PoP. Across four experiments the reversal of the PoP effect (i) depended critically on the response-stimulus interval between trials, (ii) was remarkably stable across long experimental sessions, (iii) was observed within trial-pairs when participants engaged in visual imagery, but not between trial-pairs when participants did not, and (iv) appeared to be more robust with self-paced trial-pairs than with a long continuous run of trials. Together, these results offer strong confirmation of the idea that self-generated visual imagery can produce robust reversals of the PoP effect.

Remembering 'primed' words: The effect of prime encoding demands.

Rosner, Lopez-Benitez, D'Angelo, Thomson, and Milliken (2017) reported a novel recognition memory effect using an immediate repetition method during the study phase. During each trial of an incidental study phase, participants named a target word that followed a prime word that had the same identity (repeated trials) or a different identity (not-repeated trials). Recognition in the following test phase was better for the not-repeated trials. In the present study, we examined the influence of prime encoding demands on this counterintuitive effect. In Experiment 1, we instructed 1 group to simply ignore the prime, as in the original study. A second group completed a divided attention task on prime presentation. Recognition memory was better for not-repeated than repeated words in both groups. In Experiment 2, encoding of the prime varied across 3 groups: 1 group named each prime, a second group counted the vowels in each prime, and a third group made a semantic discrimination for each prime. Recognition was better for repeated than for not-repeated words in the semantic group and did not differ across conditions for the other 2 groups. Finally, in Experiment 3, we assessed memory for not-repeated primes in addition to memory for targets (as in Experiments 1 and 2). The results confirmed that poor memory for the primes plays a significant role in producing the previously described effects. The results are discussed in relation to transient processing adaptations that affect memory encoding. (PsycINFO Database Record