Single-target Trials Research Articles

The role of facial distinctiveness in the prioritisation of targets in disjunctive dual-target face search

Two experiments explored the search for pairs of faces in a disjunctive dual-target face search (DDTFS) task for unfamiliar face targets. The distinctiveness of the target was manipulated such that both faces were typical or distinctive or contained one typical and one distinctive target. Targets were searched for in arrays of eight faces. In Experiment 1, participants completed a DDTFS block with targets learnt over the block of trials. In Experiment 2, the dual-target block was preceded by two training blocks of single-target trials. Participants also completed the upright and inverted long-form Cambridge Face Memory Test (CFMT+). The results showed that searching for two typical faces leads to one target being prioritised at the expense of the other. The ability to search for non-prioritised typical faces was associated with scores on the CFMT+. This association disappeared when faces were learnt before completing DDTFS. We interpret the findings in terms of the impact of typicality on face learning, individual differences in the ability to learn faces, and the involvement of capacity-limited working memory in the search for unfamiliar faces. The findings have implications for security-related situations where agents must search for multiple unfamiliar faces having been shown their images.

The architecture of working memory: Features from multiple remembered objects produce parallel, coactive guidance of attention in visual search.

Theories of working memory (WM) differ in their claims about the number of items that can be maintained in a state that directly interacts with other, ongoing cognitive operations (termed the focus of attention). A similar debate has arisen in the literature on visual working memory (VWM), focused on the number of items that can simultaneously interact with attentional priority. In 3 experiments, we used a redundancy-gain paradigm to provide a comprehensive test of the latter question. Participants searched for 2 cued features (e.g., a color and a shape) within a search array. The cued feature values changed on a trial-by-trial basis, requiring VWM. The target (when present) could match 1 of the cued features (single-target trials) or both cued features (redundant-target trials). We tested whether response time distributions contained a substantial proportion of trials with redundant-target responses that were faster than predicted by 2 independent guidance processes operating in parallel (i.e., violations of the race-model inequality). Violations are consistent with a coactive architecture in which both cued values guide attention in parallel and sum on the priority map. Robust violations were observed in all cases predicted by the hypothesis that multiple items in VWM can guide attention simultaneously, and these results were inconsistent with the hypothesis that guidance is limited to a single item simultaneously. When considered in the larger context of the literature on VWM and attention, the present results are consistent with a model of WM architecture in which the focus of attention can maintain multiple, independent representations. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

How to correctly put the "subsequent" in subsequent search miss errors.

Visual search, finding targets among distractors, is theoretically interesting and practically important as it involves many cognitive abilities and is vital for several critical industries (e.g., radiology, baggage screening). Unfortunately, search is especially error prone when more than one target is present in a display (a phenomenon termed the satisfaction of search effect or the subsequent search miss effect). The general effect is that observers are more likely to miss a second target if a first was already detected. Unpacking the underlying mechanisms requires two key aspects in analysis and design. First, to speak to the "subsequent" nature of the effect, the analyses must compare performance on single-target trials to performance for a second target in dual-target displays after a first has been found. Second, the design must include single-target displays that are matched in difficulty to each dual-target display to enable fair comparisons. However, it is not clear that prior research has met these two standards simultaneously. Work from academic radiology has primarily used designs with well-matched single- and dual-target trials, but most employed analyses that do not focus solely on performance after a first target has been detected. Work from cognitive psychology has generally performed the correct analyses, but relied on unmatched single- and dual-target trials, introducing a confound that could distort the results. In the current paper, we demonstrate the impact of this confound in empirical data and provide a roadmap for proper study design and analyses.

More is better: Relative prevalence of multiple targets affects search accuracy.

In real-world searches such as airport baggage screening and radiological examinations, miss errors can be life threatening. Misses increase for additional targets after detecting an initial target, termed "subsequent search misses" (SSMs), and also when targets are more often absent than present, termed the low-prevalence effect. Real-world search tasks often contain more than one target, but the prevalence of these multitarget occasions varies. For example, a cancerous tumor sometimes coexists with a benign tumor and sometimes exists alone. This study aims to investigate how the relative prevalence of multiple targets affects search accuracy. Naive observers searched for all Ts (zero, one, or two) among Ls. In Experiment 1, SSMs occurred in small but not large set sizes, which may be explained by classic capacity limit effects such as the attentional blink and repetition blindness. Experiment 2 showed an interaction between SSMs and the relative prevalence of dual-target trials: Low prevalence of dual-target trials increased SSMs relative to high prevalence dual-target trials. The prevalence of dual-target trials did not affect accuracy on single-target trials. These results may provide a novel avenue for reducing misses by increasing the prevalence of instances with multiple targets. Future efforts should take into account the relative prevalence of multiple targets to effectively reduce life-threatening miss errors.

Deep Coverage Tissue and Cellular Proteomics Revealed IL-1β Can Independently Induce the Secretion of TNF-Associated Proteins from Human Synoviocytes.

Synovitis is a key contributor to the inflammatory environment in osteoarthritis (OA) joints. Currently, the biological therapy of OA is not satisfactory in multiple single-target trials on anti-TNF agents, or IL-1 antagonists. Systems biological understanding of the phosphorylation state in OA synovium is warranted to direct further therapeutic strategies. Therefore, in this study, we compared the human synovial phosphoproteome of the OA with the acute joint fracture subjects. We found that OA synovium had significantly more phosphoproteins, and 82 phosphoproteins could only be specifically found in all the OA samples. Differentially expressed proteins of the OA synovium were focusing on endoplasmic reticulum-/Golgi-associated secretion and negative regulation of cell proliferation, which was verified through an IL-1β-treated human synoviocyte (HS) in vitro model. With data-independent acquisition-based mass spectrometry, we found that IL-1β could induce HS to secrete proteins that were significantly associated with the endosomal/vacuolar pathway, endoplasmic reticulum/Golgi secretion, complement activation, and collagen degradation. Especially, we found that while specifically suppressing HS endocytosis, IL-1β could activate the secretion of 25 TNF-associated proteins, and the change of SERPINE2 and COL3A1 secretion was verified by immunoblotting. In conclusion, our results suggest that OA synovium has a polarized phosphoproteome to inhibit proliferation and maintain active secretion of HS, whereas IL-1β alone can transform HS to produce a synovitis-associated secretome, containing numerous TNF-associated secretory proteins in a TNF-independent mode.

The Effect of Emotional Sounds on Multiple Target Search

This study examined the effect of emotional sounds on satisfaction of search (SOS). SOS occurs when detection of a target results in a lesser chance of finding subsequent targets when searching for an unknown number of targets. Previous studies have examined factors that may influence the phenomenon, but the effect of emotional sounds is yet to be identified. Therefore, the current study investigated how emotional sound affects magnitude of the SOS effect. In addition, participants’ eye movements were recorded to determine the source of SOS errors. The search display included abstract T and L-shaped items on a cloudy background and positive and negative sounds. Results demonstrated that negative sounds produced the largest SOS effect by definition, but this was due to superior accuracy in low-salient single target trials. Response time, which represents efficiency, was consistently faster when negative sounds were provided, in all target conditions. On-target fixation classification revealed scanning error, which occurs because targets are not fixated, as the most prominent type of error. These results imply that the two dimensions of emotion - valence and arousal - interactively affect cognitive performance.

Interindividual differences in preferred directions of perceptual and motor decisions.

Both the perceptual system and the motor system can be faced with ambiguous information and then have to choose between different alternatives. Often these alternatives involve decisions about directions, and anisotropies have been reported for different tasks. Here we measured interindividual differences and temporal stability of directional preferences in eye movement, motion perception, and thumb movement tasks. In all tasks, stimuli were created such that observers had to decide between two opposite directions in each trial and preferences were measured at 12 axes around the circle. There were clear directional preferences in all utilized tasks. The strongest effects were present in tasks that involved motion, like the smooth pursuit eye movement, apparent motion, and structure-from-motion tasks. The weakest effects were present in the saccadic eye movement task. Observers with strong directional preferences in the eye movement tasks showed shorter latency costs for target-conflict trials compared to single-target trials, suggesting that directional preferences might be advantageous for solving the target conflict. Although there were consistent preferences across observers in most of the tasks, there was also considerable variability in preferred directions between observers. The magnitude of preferences and the preferred directions were correlated only between few tasks. While the magnitude of preferences varied substantially over time, the direction of these preferences was stable over several weeks. These results indicate that individually stable directional preferences exist in a range of perceptual and motor tasks.

Dissociations between spatial-attentional processes within parietal cortex: insights from hybrid spatial cueing and change detection paradigms

Spatial cueing has been used by many different groups under multiple forms to study spatial attention processes. We will present evidence obtained in brain-damaged patients and healthy volunteers using a variant of this paradigm, the hybrid spatial cueing paradigm, which, besides single-target trials with valid and invalid cues, also contains trials where a target is accompanied by a contralateral competing stimulus (competition trials). This allows one to study invalidity-related processes and selection between competing stimuli within the same paradigm. In brain-damaged patients, lesions confined to the intraparietal sulcus result in contralesional attentional deficits, both during competition and invalid trials, according to a pattern that does not differ from that observed following inferior parietal lesions. In healthy volunteers, however, selection between competing stimuli and invalidity-related processes are partially dissociable, the former relying mainly on cytoarchitectonic areas hIP1-3 in the intraparietal sulcus, the latter on cytoarchitectonic area PF in the right inferior parietal lobule. The activity profile in more posterior inferior parietal areas PFm and PGa, does not distinguish between both types of trials. The functional account for right PF and adjacent areas is further constrained by the activity profile observed during other experimental paradigms. In a change detection task with variable target and distracter set size, for example, these inferior parietal areas show highest activity when the stimulus array consists of only one single target, while the intraparietal sulcus show increased activity as the array contains more targets and distracters. Together, these findings lead us to the hypothesis that right PF functions as a target singleton detector, which is activated when a target stands out from the background, referring both to the temporal background (expectancy) and the momentaneous background (stimulus-driven saliency).

Temporal attention for visual food stimuli in restrained eaters

Although restrained eaters try to limit their food intake, they often fail and indulge in exactly those foods that they want to avoid. A possible explanation is a temporal attentional bias for food cues. It could be that for these people food stimuli are processed relatively efficiently and require less attentional resources to enter awareness. Once a food stimulus has captured attention, it may be preferentially processed and granted prioritized access to limited cognitive resources. This might help explain why restrained eaters often fail in their attempts to restrict their food intake. A Rapid Serial Visual Presentation task consisting of dual and single target trials with food and neutral pictures as targets and/or distractors was administered to restrained (n=40) and unrestrained (n=40) eaters to study temporal attentional bias. Results indicated that (1) food cues did not diminish the attentional blink in restrained eaters when presented as second target; (2) specifically restrained eaters showed an interference effect of identifying food targets on the identification of preceding neutral targets; (3) for both restrained and unrestrained eaters, food cues enhanced the attentional blink; (4) specifically in restrained eaters, food distractors elicited an attention blink in the single target trials. In restrained eaters, food cues get prioritized access to limited cognitive resources, even if this processing priority interferes with their current goals. This temporal attentional bias for food stimuli might help explain why restrained eaters typically have difficulties maintaining their diet rules.

Redundancy gain for semantic features

In a go/no-go experiment, semantic redundancy gain was assessed for responses to single written words. Specifically, we asked participants to respond only to words whose meaning matched at least one semantic target feature-that is, the target category (e.g., animal), the target color (e.g., gray), or both. On redundant-target trials, the word (e.g., elephant) matched both semantic target features (i.e., gray and animal). On single-target trials, the word (e.g., beaver) matched one target feature (i.e., animal) and a nontarget feature (i.e., brown). We observed shorter reaction times in the redundant-target condition than in the faster single-target condition. Hence, the present study provides the first evidence that redundancy gain is not limited to responses to redundant proximal stimulus features but can also be observed for responses to semantic feature information.

Averaging saccades are repelled by prior uninformative cues at both short and long intervals

When two spatially proximal stimuli are presented simultaneously, a first saccade is often directed to an intermediate location between the stimuli (averaging saccade). In an earlier study, Watanabe (2001) showed that, at a long cue–target onset asynchrony (CTOA; 600 ms), uninformative cues not only slowed saccadic response times (SRTs) to targets presented at the cued location in single target trials (inhibition of return, IOR), but also biased averaging saccades away from the cue in double target trials. The present study replicated Watanabe's experimental task with a short CTOA (50 ms), as well as with mixed short (50 ms) and long (600 ms) CTOAs. In all conditions on double target trials, uninformative cues robustly biased averaging saccades away from cued locations. Although SRTs on single target trials were delayed at previously cued locations at both CTOAs when they were mixed, this delay was not observed in the blocked, short CTOA condition. We suggest that top-down factors, such as expectation and attentional control settings, may have asymmetric effects on the temporal and spatial dynamics of oculomotor processing.

Interactions between Reward, Feedback, and Timing Structures on Dual-Target Search Performance

Individuals who conduct visual searches that can contain more than one target face many challenges. Such multiple-target visual searches can be especially error prone, as identification of one target often makes identification of a second target less likely. Given that many real-world searches can be multiple-target searches (e.g., radiological examinations, baggage screening, military searches), it is important to understand what can affect performance. Multiple-target search is particularly sensitive to top-down influences such as anticipatory anxiety (Cain, Dunsmoor, LaBar, & Mitroff, VSS 2011), and here we explore the impact of reward motivation. Participants completed a paradigm that reliably produces dual-target errors (Fleck, Samei, & Mitroff, 2010). When we simply motivated participants with a performance-based, ten-percent chance of winning an additional d50 in compensation (Experiment 1), the performance decline on dual-target trials was eliminated, while accuracy on single-target trials remained the same. Further, without monetary motivation, adding trial-by-trial feedback (Experiment 2) did not significantly improve dual-target accuracy; however, the presence of both monetary motivation and feedback (Experiment 3) resulted in substantial performance benefits for both single- and dual-target conditions compared to Experiments 1 and 2. Finally, in the presence of top-down monetary motivation, trial-based time limits (Experiment 4) did not affect performance (i.e., participants performed equivalently with or without a time limit). This is in contrast to prior data without monetary incentives (Fleck et al., 2010), in which time limits negatively affected performance. Collectively, these experiments demonstrate that (1) motivation alone is sufficient to enhance dual-target search performance, (2) such benefits are enhanced when paired with trial-by-trial feedback, and (3) time limits hurt performance in the absence of motivation but have no effect with motivation. These findings provide key information about the role of top-down motivation on performance and how this can successfully improve performance on critical dual-target searches.

Reducing Satisfaction of Search Errors in Visual Search

Several occupations rely upon the ability to accurately and efficiently perform visual search. For example, radiologists must successfully identify abnormalities, and airport luggage screeners must recognize threatening items. By investigating various aspects of such searches, psychological research can reveal ways to improve search performance. We (Fleck, Samei, & Mitroff, in press) have recently focused on one specific influence that had previously been explored almost exclusively within the study of radiology: Satisfaction of Search (SOS), wherein the successful detection of one target can reduce detection of a second target in the same search array. To eliminate SOS errors, we must delineate the sources of the errors. Combined with our prior work, here we examine the specific roles of target heterogeneity and the decision-making component of target-distractor discrimination (i.e., how easy it is to determine whether a stimulus is a target or a distractor). In the current experiments, subjects searched arrays of line-drawn objects for targets of two different categories (tools and bottles) amongst several categories of distractor objects. On any given trial, there could be no targets, one target (either a tool or bottle), or two targets (both a tool and a bottle). The relative occurrence of these trial types varied across experiments. Compared to previous experiments that employed homogeneous targets and that required effortful evaluation to discriminate targets from distractors, the SOS effect was reduced here. That is, search accuracy for easily discriminable, heterogeneous objects was no worse for dual-target trials than for single-target trials. These results suggest that target heterogeneity and target-distractor discriminability may both play key roles in multiple target search accuracy.

Tomatoes and Apples or Red and Green Lines: Are Age-Related Interference Effects Based on Competition Among Concepts or Percepts?

Using a negative priming paradigm, the authors tested whether age-related interference effects are due to age differences in perceptual distractibility or in resolving conceptual competition. In samples of 40 younger adults (aged 22–34) and 40 older adults (aged 58–76), the authors found a greater reduction in processing speed for older than for younger adults in trials in which targets were superimposed with distracting objects as compared to single-target trials. When trials were paralleled for perceptual features, that is, when single-target trials were supplemented with nonsense distractors, the age effect became nonsignificant. The results suggest that age-related interference effects are primarily due to age differences in perceptual distractibility.

Corrigenda

Corrigenda

Shared target selection for combined version-vergence eye movements.

Primates frequently make rapid binocular eye movements to reorient gaze in both direction and depth. To explain the unequal movements made by the two eyes, it often is assumed that they result from the combined action of a conjugate saccadic system and a vergence contribution. Clearly such a scheme can only yield coordinated binocular movements if both systems are guided by a shared or coupled target selection mechanism. To investigate the degree of cooperation at this level, we studied binocular refixations to target-nontarget double-stimuli in three-dimensional (3-D) space. Binocular eye movements were recorded in seven subjects using the scleral coil technique. In the experiments, 20% of trials were composed of a green target and a red nontarget, presented at the same time, but at different locations in 3-D space. These were alternated randomly with single-target trials (80%) in which the green stimulus was presented randomly at one of eight possible positions in 3-D space. Instructions to the subject emphasized either the speed or accuracy of response. Our findings show that typical features of the saccadic response to double-stimuli (bistability, averaging, and a speed-accuracy trade-off), as found in earlier two-dimensional studies, are also prevalent for initial binocular refixations to double stimuli in 3-D space. When the first saccadic response is directed to one of the two stimuli, the vergence system almost invariably makes the same choice. Likewise, when the saccadic system makes a short-latency averaging response, the vergence system shows a similar compromise. Statistical analysis shows a high correlation between saccadic and vergence target selection, strongly suggesting that the amplitude computation process of both subsystems is due to a common target selection stage that has access to information about stimulus location in 3-D space.

Processing redundant signals: coactivation, divided attention, or what?

The evidence for and against a redundancy gain in reaction time (RT) when the target is repeated in the visual display is reviewed. We consider the relevance of redundancy gains under these circumstances to the question of whether attention can be simultaneously directed to separate locations in the visual field. In the present experiments, two capital letters were the target stimuli in a two-alternative forced-choice RT paradigm. In addition to the usual conditions of single-target trials, trials on which the target is repeated in the display, and trials on which the target occurs with a noise letter, we introduced the innovation of a condition in which both targets occur in the display. In our two experiments, RT was fastest with single-target displays and slowest with displays containing a target and a noise letter. There was no significant difference in RT to displays in which the target was repeated and displays in which both targets were presented. Both conditions showed a redundancy gain when compared with displays containing a target and a noise letter. The lack of response competition in the both-targets condition and the overall pattern of the results were well explained by a unitary attentional focus that serially processed the letters in the display. Analyses of minima and maxima RTs were consistent with this interpretation.

Absence of a redundant-signals effect in a reaction time task with divided attention.

In letter-identification reaction time experiments, a redundant-signals advantage was obtained when one location contained an irrelevant letter on single-target trials. It was not obtained when the position was blank. This confirms a prediction from a previous analysis in terms of variable criterion theory. The intercept of the linear function relating the growth of excitatory strength for redundant targets to that for the sum of single-target strengths is determined by the presence or absence of an irrelevant distractor. This confirms a second prediction. In this task, the redundant-signals advantage is due to distraction from an irrelevant stimulus occupying a relevant location. There is also evidence for a smaller distraction effect even from a redundant target. These findings are inconsistent with predictions of separate activation theory. Apparent differences be-tween these results and those of tachistoscopic recognition experiments are discussed.

Some evidence for correlated separate activation in a simple letter-detection task.

This study investigates the separate activation versus coactivation issue for redundant targets in a simple letter-detection paradigm with latency as the dependent variable. The results of a one-response visual-search task are reported. Since, on single-target trials, only the target was presented and no accompanying noise element, no “distraction decrement” caused by irrelevant noise elements (Grice et al., 1984) was to be expected. The data obtained showed a clear redundantsignal effect. Subsequent detailed analysis of the latency data using Miller’s (1982) procedure indicated that the results were consistent with a separate activation model and failed to provide convincing evidence in favor of coactivation models. A further analysis of the data indicated that, in the present study, the separate channels were negatively correlated for a range of fast RTs and positively correlated for intermediate and larger RTs. No evidence in favor of Grice et al.’s (1984) distraction-decrement hypothesis was found. The conclusions of this study are that (1) a separate activation model summarizes the essential features of information processing in this simple visual search task, and (2) no convincing evidence in favor of coactivation in visual search tasks has been reported in the literature up to now.