Fatigue and vigilance in medical experts detecting breast cancer.

An abundance of laboratory-based experiments has described a vigilance decrement of reducing accuracy to detect targets with time on task, but there are few real-world studies, none of which have previously controlled the environment to control for bias. We describe accuracy in clinical practice for 360 experts who examined >1 million women's mammograms for signs of cancer, whilst controlling for potential biases. The vigilance decrement pattern was not observed. Instead, test accuracy improved over time, through a reduction in false alarms and an increase in speed, with no significant change in sensitivity. The multiple-decision model explains why experts miss targets in low prevalence settings through a change in decision threshold and search quit threshold and propose it should be adapted to explain these observed patterns of accuracy with time on task. What is typically thought of as standard and robust research findings in controlled laboratory settings may not directly apply to real-world environments and instead large, controlled studies in relevant environments are needed.

Framing the fallibility of Computer-Aided Detection aids cancer detection.

Computer-Aided Detection (CAD) has been proposed to help operators search for cancers in mammograms. Previous studies have found that although accurate CAD leads to an improvement in cancer detection, inaccurate CAD leads to an increase in both missed cancers and false alarms. This is known as the over-reliance effect. We investigated whether providing framing statements of CAD fallibility could keep the benefits of CAD while reducing over-reliance. In Experiment 1, participants were told about the benefits or costs of CAD, prior to the experiment. Experiment 2 was similar, except that participants were given a stronger warning and instruction set in relation to the costs of CAD. The results showed that although there was no effect of framing in Experiment 1, a stronger message in Experiment 2 led to a reduction in the over-reliance effect. A similar result was found in Experiment 3 where the target had a lower prevalence. The results show that although the presence of CAD can result in over-reliance on the technology, these effects can be mitigated by framing and instruction sets in relation to CAD fallibility.

Telephone conversations affect the executive but not the alerting or orienting network.

Previous work has shown that talking on a mobile phone leads to an impairment of visual attention. Gunnell et al. (2020) investigated the locus of these dual-task impairments and found that although phone conversations led to cognitive delays in response times, other mechanisms underlying particular selective attention tasks were unaffected. Here, we investigated which attentional networks, if any, were impaired by having a phone conversation. We used the attentional network task (ANT) to evaluate performance of the alerting, orienting, and executive attentional networks, both in conditions where people were engaged in a conversation and where they were silent. Two experiments showed that there was a robust delay in response across all three networks. However, at the individual network level, holding a conversation did not influence the size of the alerting or orienting effects but it did reduce the size of the conflict effect within the executive network. The findings suggest that holding a conversation can reduce the overall speed of responding and, via its influence on the executive network, can reduce the amount of information that can be processed from the environment. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The optimal use of computer aided detection to find low prevalence cancers.

People miss a high proportion of targets that only appear rarely. This low prevalence (LP) effect has implications for applied search tasks such as the clinical reading of mammograms. Computer aided detection (CAD) has been used to help radiologists search mammograms by highlighting areas likely to contain a cancer. Previous research has found a benefit in search when CAD cues were correct but a cost to search when CAD cues were incorrect. The current research investigated whether there is an optimal way to present CAD to ensure low error rates when CAD is both correct and incorrect. Experiment 1 compared an automatic condition, where CAD appeared simultaneously with the display to an interactive condition, where participants could choose to use CAD. Experiment 2 compared the automatic condition to a confirm condition, where participants searched the display first before being shown the CAD cues. The results showed that miss errors were reduced overall in the confirm condition, with no cost to false alarms. Furthermore, having CAD be interactive, resulted in a low uptake where it was only used in 34% of trials. The results showed that the presentation mode of CAD can affect decision-making in LP search.

Double reading reduces miss errors in low prevalence search.

Low prevalence studies show that people miss a large proportion of targets if they appear rarely. This finding has implications for real-world tasks, such as mammography, where it is important to detect infrequently appearing cancers. We examined whether having people search in pairs in a "double reading" procedure reduces miss errors in low prevalence search compared with when participants search the displays alone. In Experiment 1 pairs of participants searched for a mass in a laboratory mammogram task. Participants either searched the same display together (in the same room) or searched the displays independently (in separate rooms). Experiment 2 further manipulated the reading order so that paired participants either read the mammograms in the same or different orders. The results showed that, although there was no effect of reading order, double reading led to a substantial reduction in miss errors compared with single reading conditions. Furthermore, the reason for the double reading improvement differed across reading environments: When participants read the displays in a shared environment (i.e., in the same room) the improvement occurred due to an increase in sensitivity; however, when participants read the display in different rooms the improvement occurred due to a change in response bias. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Having a phone conversation delays but does not disrupt cognitive mechanisms.

Previous research has shown that talking on a mobile phone leads to impairments in a number of cognitive tasks. However, it is not yet known whether the act of conversation disrupts the underlying cognitive mechanisms (the Cognitive Disruption hypothesis) or leads to a delay in response due to a limit on central cognitive resources (the Cognitive Delay hypothesis). We investigated this here using two cognitive search tasks that investigate spatial learning and time-based selection: Contextual Cueing and Visual Marking. In Contextual Cueing, responses to repeated displays are faster than those to novel displays. In Visual Marking, participants prioritize attention to new information and deprioritize old, unimportant information (the Preview Benefit). Experiments 1 to 3 investigated whether Contextual Cueing occurred while people were engaged in a phone conversation, whereas Experiments 4 to 6 investigated whether a Preview Benefit occurred, again while people were engaged in conversation. The results showed that having a conversation did not interfere with the mechanisms underlying spatial learning or time-based selection. However, in all experiments there was a significant increase in response times. The results are consistent with a Cognitive Delay account explaining the dual-task cost of having a phone conversation on concurrent cognitive tasks. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

The hazards of perception: evaluating a change blindness demonstration within a real-world driver education course.

Overconfidence in one's driving ability can lead to risky decision-making and may therefore increase the accident risk. When educating people about the risks of their driving behavior, it is all too easy for individuals to assume that the message is not meant for them and so can be ignored. In this study we developed and assessed the effect of a road safety demonstration based around the phenomenon of change blindness within a real-world Driver Awareness Course. We collected quantitative and qualitative data to evaluate the effectiveness of the demonstration in both a police-led environment (Experiment 1) and a laboratory environment (Experiment 2). We also compared the change blindness intervention to two control tasks. The results showed that participants' self-reported ability to spot important visual changes was reduced after the change blindness demonstration in both experiments, but was not reduced after participation in the control tasks of Experiment 2. Furthermore, participants described the change blindness demonstrations positively and would recommend that they were shown more widely.

It is not good to talk: conversation has a fixed interference cost on attention regardless of difficulty.

It is well-documented that telephone conversations lead to impaired driving performance. Kunar et al. (Psychon Bull Rev 15:1135-1140, 2008) showed that this deficit was, in part, due to a dual-task cost of conversation on sustained visual attention. Using a multiple object tracking (MOT) task they found that the act of conversing on a hands-free telephone resulted in slower response times and increased errors compared to when participants performed the MOT task alone. The current study investigates whether the dual-task impairment of conversation on sustained attention is affected by conversation difficulty or task difficulty, and whether there was a dual-task deficit on attention when participants overheard half a conversation. Experiment 1 manipulated conversation difficulty by asking participants to discuss either easy questions or difficult questions. The results showed that there was no difference in the dual-task cost depending on conversation difficulty. Experiment 2 showed a similar dual-task deficit of attention in both an easy and a difficult visual search task. Experiments 3 and 4 showed that in contrast to work using a dot tracking and choice reaction time task (Emberson et al., Psychol Sci 21:1383-1388, 2010), there was little deficit on MOT performance of hearing half a conversation, provided people heard the conversations in their native language. The results are discussed in terms of a resource-depleted account of attentional resources showing a fixed conversational-interference cost on attention.

The influence of attention on value integration.

People often have to make decisions based on many pieces of information. Previous work has found that people are able to integrate values presented in a rapid serial visual presentation (RSVP) stream to make informed judgements on the overall stream value (Tsetsos et al. Proceedings of the National Academy of Sciences of the United States of America, 109(24), 9659-9664, 2012). It is also well known that attentional mechanisms influence how people process information. However, it is unknown how attentional factors impact value judgements of integrated material. The current study is the first of its kind to investigate whether value judgements are influenced by attentional processes when assimilating information. Experiments 1-3 examined whether the attentional salience of an item within an RSVP stream affected judgements of overall stream value. The results showed that the presence of an irrelevant high or low value salient item biased people to judge the stream as having a higher or lower overall mean value, respectively. Experiments 4-7 directly tested Tsetsos et al.'s (Proceedings of the National Academy of Sciences of the United States of America, 109(24), 9659-9664, 2012) theory examining whether extreme values in an RSVP stream become over-weighted, thereby capturing attention more than other values in the stream. The results showed that the presence of both a high (Experiments 4, 6 and 7) and a low (Experiment 5) value outlier captures attention leading to less accurate report of subsequent items in the stream. Taken together, the results showed that valuations can be influenced by attentional processes, and can lead to less accurate subjective judgements.

Low prevalence search for cancers in mammograms: Evidence using laboratory experiments and computer aided detection.

People miss a large proportion of targets when they only appear rarely. This Low Prevalence (LP) Effect could lead to serious consequences if it occurred in the real-world task of searching for cancers in mammograms. Using a novel mammogram search task, we asked participants to search for a prespecified cancer (Experiments 1-2) or a range of masses (Experiments 3-5) under high or low prevalence conditions. Experiment 1 showed that an LP Effect occurred using these stimuli. Experiment 2 tested an overreliance hypothesis and showed that the use of Computer Aided Detection (CAD) led to fewer missed cancers with a valid CAD prompt yet, a large proportion of cancers were missed when CAD was incorrect. Experiment 3-5 showed that false alarms also increased when searching for a range of masses and that CAD reduced miss errors when it correctly cued the target but increased miss errors and false alarms when it did not. Furthermore, when a mass fell outside the CAD prompt it was more likely to be misidentified. No LP Effect was observed with the addition of CAD when people were asked to search for a range of targets. Theories and implications for mammogram search are discussed. (PsycINFO Database Record

The downside of choice: Having a choice benefits enjoyment, but at a cost to efficiency and time in visual search.

The efficiency of how people search for an item in visual search has, traditionally, been thought to depend on bottom-up or top-down guidance cues. However, recent research has shown that the rate at which people visually search through a display is also affected by cognitive strategies. In this study, we investigated the role of choice in visual search, by asking whether giving people a choice alters both preference for a cognitively neutral task and search behavior. Two visual search conditions were examined: one in which participants were given a choice of visual search task (the choice condition), and one in which participants did not have a choice (the no-choice condition). The results showed that the participants in the choice condition rated the task as both more enjoyable and likeable than did the participants in the no-choice condition. However, despite their preferences, actual search performance was slower and less efficient in the choice condition than in the no-choice condition (Exp. 1). Experiment 2 showed that the difference in search performance between the choice and no-choice conditions disappeared when central executive processes became occupied with a task-switching task. These data concur with a choice-impaired hypothesis of search, in which having a choice leads to more motivated, active search involving executive processes.

When are abrupt onsets found efficiently in complex visual search? Evidence from multielement asynchronous dynamic search.

Previous work has found that search principles derived from simple visual search tasks do not necessarily apply to more complex search tasks. Using a Multielement Asynchronous Dynamic (MAD) visual search task, in which high numbers of stimuli could either be moving, stationary, and/or changing in luminance, Kunar and Watson (M. A Kunar & D. G. Watson, 2011, Visual search in a Multi-element Asynchronous Dynamic (MAD) world, Journal of Experimental Psychology: Human Perception and Performance, Vol 37, pp. 1017-1031) found that, unlike previous work, participants missed a higher number of targets with search for moving items worse than for static items and that there was no benefit for finding targets that showed a luminance onset. In the present research, we investigated why luminance onsets do not capture attention and whether luminance onsets can ever capture attention in MAD search. Experiment 1 investigated whether blinking stimuli, which abruptly offset for 100 ms before reonsetting--conditions known to produce attentional capture in simpler visual search tasks--captured attention in MAD search, and Experiments 2-5 investigated whether giving participants advance knowledge and preexposure to the blinking cues produced efficient search for blinking targets. Experiments 6-9 investigated whether unique luminance onsets, unique motion, or unique stationary items captured attention. The results found that luminance onsets captured attention in MAD search only when they were unique, consistent with a top-down unique feature hypothesis.

Negative emotional stimuli reduce contextual cueing but not response times in inefficient search.

In visual search, previous work has shown that negative stimuli narrow the focus of attention and speed reaction times (RTs). This paper investigates these two effects by first asking whether negative emotional stimuli narrow the focus of attention to reduce the learning of a display context in a contextual cueing task and, second, whether exposure to negative stimuli also reduces RTs in inefficient search tasks. In Experiment 1, participants viewed either negative or neutral images (faces or scenes) prior to a contextual cueing task. In a typical contextual cueing experiment, RTs are reduced if displays are repeated across the experiment compared with novel displays that are not repeated. The results showed that a smaller contextual cueing effect was obtained after participants viewed negative stimuli than when they viewed neutral stimuli. However, in contrast to previous work, overall search RTs were not faster after viewing negative stimuli (Experiments 2 to 4). The findings are discussed in terms of the impact of emotional content on visual processing and the ability to use scene context to help facilitate search.

A configural dominant account of contextual cueing: Configural cues are stronger than colour cues.

Previous work has shown that reaction times to find a target in displays that have been repeated are faster than those for displays that have never been seen before. This learning effect, termed "contextual cueing" (CC), has been shown using contexts such as the configuration of the distractors in the display and the background colour. However, it is not clear how these two contexts interact to facilitate search. We investigated this here by comparing the strengths of these two cues when they appeared together. In Experiment 1, participants searched for a target that was cued by both colour and distractor configural cues, compared with when the target was only predicted by configural information. The results showed that the addition of a colour cue did not increase contextual cueing. In Experiment 2, participants searched for a target that was cued by both colour and distractor configuration compared with when the target was only cued by colour. The results showed that adding a predictive configural cue led to a stronger CC benefit. Experiments 3 and 4 tested the disruptive effects of removing either a learned colour cue or a learned configural cue and whether there was cue competition when colour and configural cues were presented together. Removing the configural cue was more disruptive to CC than removing colour, and configural learning was shown to overshadow the learning of colour cues. The data support a configural dominant account of CC, where configural cues act as the stronger cue in comparison to colour when they are presented together.

Colour and spatial cueing in low-prevalence visual search.

In visual search, 30-40% of targets with a prevalence rate of 2% are missed, compared to 7% of targets with a prevalence rate of 50% (Wolfe, Horowitz, & Kenner, 2005). This "low-prevalence" (LP) effect is thought to occur as participants are making motor errors, changing their response criteria, and/or quitting their search too soon. We investigate whether colour and spatial cues, known to improve visual search when the target has a high prevalence (HP), benefit search when the target is rare. Experiments 1 and 2 showed that although knowledge of the target's colour reduces miss errors overall, it does not eliminate the LP effect as more targets were missed at LP than at HP. Furthermore, detection of a rare target is significantly impaired if it appears in an unexpected colour-more so than if the prevalence of the target is high (Experiment 2). Experiment 3 showed that, if a rare target is exogenously cued, target detection is improved but still impaired relative to high-prevalence conditions. Furthermore, if the cue is absent or invalid, the percentage of missed targets increases. Participants were given the option to correct motor errors in all three experiments, which reduced but did not eliminate the LP effect. The results suggest that although valid colour and spatial cues improve target detection, participants still miss more targets at LP than at HP. Furthermore, invalid cues at LP are very costly in terms of miss errors. We discuss our findings in relation to current theories and applications of LP search.

Determining the capacity of time-based selection.

In visual search, a set of distractor items can be suppressed from future selection if they are presented (previewed) before a second set of search items arrive. This visual marking mechanism provides a top-down way of prioritizing the selection of new stimuli, at the expense of old stimuli already in the field (Watson & Humphreys, 1997). Typically, this preview benefit has been examined by measuring the efficiency of detecting a target item contained within a newly presented set. Such work has led to the suggestion that the capacity of the visual marking mechanism is extremely high. Here we present five experiments which measured performance for selecting and responding to all the new stimuli rather than a single target item within the new set. The findings illustrate that when selecting and responding to all new items intentionally trying to prioritize new stimuli has a capacity limit of approximately six to seven items and that this limit depends partly on properties of the stimuli. The findings are discussed in terms of mechanisms of time-based selection, attentional capacity limits, and the task demands of multiple item selection.

Target absent trials in configural contextual cuing.

In contextual cuing (CC), reaction times for finding targets are faster in repeated displays than in displays that have never been seen before. This has been demonstrated using target-distractor configurations, global background colors, naturalistic scenes, and covariation of targets with distractors. The majority of CC studies have used displays in which the target is always present. This study investigated what happens when the target is sometimes absent. Experiment 1 showed that, although configural CC occurs in displays when the target is always present, there is no CC when the target is always absent. Experiment 2 showed that there is no CC when the same spatial layout can be both target present and target absent on different trials. The presence of distractors in locations that had contained targets on other trials appeared to interfere with CC, and even disrupted the expression of CC in previously learned contexts (Exps. 3-5). These results show that target-distractor associations are the important element in producing CC and that, consistent with a response selection account, changing the response type from an orientation task to a detection task removes the CC effect.

Visual search in a multi-element asynchronous dynamic (MAD) world.

In visual search tasks participants search for a target among distractors in strictly controlled displays. We show that visual search principles observed in these tasks do not necessarily apply in more ecologically valid search conditions, using dynamic and complex displays. A multi-element asynchronous dynamic (MAD) visual search was developed in which the stimuli could either be moving, stationary, and/or changing in luminance. The set sizes were high and participants did not know the specific target template. Experiments 1 through 4 showed that, contrary to previous studies, search for moving items was less efficient than search for static items and targets were missed a high percentage of the time. However, error rates were reduced when participants knew the exact target template (Experiment 5) and the difference in search efficiency for moving and stationary targets disappeared when lower set sizes were used (Experiment 6). In all experiments there was no benefit to finding targets defined by a luminance change. The data show that visual search principles previously shown in the literature do not apply to these more complex and "realistically" driven displays.

Visual marking and change blindness: moving occluders and transient masks neutralize shape changes to ignored objects.

Visual search efficiency improves by presenting (previewing) one set of distractors before the target and remaining distractor items (D. G. Watson & G. W. Humphreys, 1997). Previous work has shown that this preview benefit is abolished if the old items change their shape when the new items are added (e.g., D. G. Watson & G. W. Humphreys, 2002). Here we present 5 experiments that examined whether such object changes are still effective in recapturing attention if the changes occur while the previewed objects are occluded or masked. Overall, the findings suggest that masking transients are effective in preventing both object changes and the presentation of new objects from capturing attention in time-based visual search conditions. The findings are discussed in relation to theories of change blindness, new object capture, and the ecological properties of time-based visual selection.

Spatial and temporal separation fails to counteract the effects of low prevalence in visual search.

Recent research has shown that, in visual search, participants can miss 30-40% of targets when they only appear rarely (i.e. on 1-2% of trials). Low target prevalence alters the behavior of the searcher. It can lead participants to quit their search prematurely (Wolfe et al., 2005), to shift their decision criteria (Wolfe et al., 2007) and/or to make motor or response errors (Fleck & Mitroff, 2007). In this paper we examine whether the LP Effect can be ameliorated if we split the search set in two, spreading the task out over space and/or time. Observers searched for the letter "T" among "L"s. In Experiment 1, the left or right half of the display was presented to the participants before the second half. In Experiment 2, items were spatially intermixed but half of the items were presented first, followed by the second half. Experiment 3 followed the methods of Experiment 2 but allowed observers to correct perceived errors. All three experiments produced robust low prevalence (LP) effects with higher errors at 2% prevalence than at 50% prevalence. Dividing up the display had no beneficial effect on errors. The opportunity to correct errors reduced but did not eliminate the LP effect. Low prevalence continues to elevate errors even when observers are forced to slow down and permitted to correct errors.