Worth a quick look? Initial scene previews can guide eye movements as a function of domain-specific expertise but can also have unforeseen costs

Rapid scene recognition is a global visual process we can all exploit to guide search. This ability is thought to underpin expertise in medical image perception yet there is no direct evidence that isolates the expertise-specific contribution of processing scene previews on subsequent eye movement performance. We used the flash-preview moving window paradigm (Castelhano & Henderson, 2007) to investigate this issue. Expert radiologists and novice observers underwent 2 experiments whereby participants either saw a 250ms scene preview or a mask before searching for a target. Observers looked for everyday objects from real-world scenes (Experiment 1), and searched for lung nodules from medical images (Experiment 2). Both expertise groups exploited the brief preview of the upcoming scene to more efficiently guide windowed search in Experiment 1, but there was only a weak effect of domain-specific expertise in Experiment 2, with experts showing small improvements in search metrics with scene previews. Expert diagnostic performance was better than novices in all conditions but was not contingent on seeing the scene preview, and scene preview actually impaired novice diagnostic performance. Experiment 3 required novice and experienced observers to search for a variety abnormalities from different medical images. Rather than maximising the expertise-specific advantage of processing scene previews, both novices and experienced radiographers were worse at detecting abnormalities with scene previews. We discuss how restricting access to the initial glimpse can be compensated for by subsequent search and discovery processing, but there can still be costs in integrating a fleeting glimpse of a medical scene

Looking for cancer: Expertise related differences in searching and decision making

We examined how the ability to detect lung nodules in chest x-ray inspection is reflected in experience-related differences in visual search and decision making, and whether the eye-tracking metric time-to-first hit showed systematic decreases across expertise levels are examined. In the study decision making improved with expertise, however, time-to-first fixate a nodule showed only a non-significant trend to decrease with expertise. Surprisingly, naïve and expert observers allocated less visual attention at nodules compared with first and third year radiography students. This similarity in visual attention at nodules but not in decision making was explained by the fact that naïve observers were more likely to fixate and make errors on distracter regions. Time-to-first hit has been linked to expert performance in mammography, but in this study was not sufficiently sensitive to demonstrate clear linear improvements across expertise groups. This brings into question the use of this metric as an indirect measure of rapid initial holistic processing

Expecting the initial glimpse: prior target knowledge activation or repeated search does not eliminate scene preview search benefits

A brief glimpse of a scene can guide eye movements but it remains unclear how prior target knowledge influences early scene processing. Using the ‘flash-preview moving window’ (FPMW) paradigm to restrict peripheral vision during search, we manipulated whether target identity was presented before or after previews. Windowed search was more efficient following 250 ms scene previews, and knowing target identity beforehand further improved how search was initiated and executed. However, in Experiment 2 when targets were removed from scene previews, only the initiation of search continued to be modulated by prior activation of target knowledge. Experiment 3 showed that search benefits from scene previews are maintained even when repeatedly searching through the same type of scene for the same type of target. Experiment 4 replicated Experiment 3 whilst also controlling for differences in integration times. We discuss the flexibility of the FPMW paradigm to measure how the first glimpse affects search

The flash-preview moving window paradigm: Unpacking visual expertise one glimpse at a time

How we make sense of what we see and where best to look is shaped by our experience, our current task goals and how we first perceive our environment. An established way of demonstrating these factors work together is to study how eye movement patterns change as a function of expertise and to observe how experts can solve complex tasks after only very brief glances at a domain-specific image. The primary focus of this paper is to introduce an innovative gaze-contingent method called the ‘Flash-Preview Moving Window’ (FPMW) paradigm (Castelhano & Henderson, 2007), which was recently developed to understand our shared expertise in scene perception and how our first glimpse of a scene is used to guide our eye movement behaviour. In keeping with this special issue on visual expertise and medicine, this paper will highlight how the FPMW paradigm has the potential to resolve long-standing theoretical issues as to how, right from the very first glance, experts are able to process domain-specific images and guide their eye movements better than novices. Since FPMW is a gaze-contingent eye-tracking method, the paper will first outline the current methodological and theoretical frontier, and how the FPMW paradigm bridges established methods used to investigate visual expertise. The paper will discuss a recent example in which the FPMW was employed to investigate medical image perception expertise for the first time (Litchfield & Donovan, 2016), and by discussing the insights and challenges this method offers, this should ultimately deepen our understanding of visual expertise

When distraction helps: Evidence that concurrent articulation and irrelevant speech can facilitate insight problem solving

We report an experiment investigating the “special-process” theory of insight problem solving, which claims that insight arises from non-conscious, non-reportable processes that enable problem re-structuring. We predicted that reducing opportunities for speech-based processing during insight problem solving should permit special processes to function more effectively and gain conscious awareness, thereby facilitating insight. We distracted speech-based processing by using either articulatory suppression or irrelevant speech, with findings for these conditions supporting the predicted insight facilitation effect relative to silent working or thinking aloud. The latter condition was included to investigate the currently contested effect of “verbal overshadowing” on insight, whereby thinking aloud is claimed to hinder the operation of special, non-reportable processes. Whilst verbal overshadowing was not evident in final solution rates, there was nevertheless support for verbal overshadowing up to and beyond the mid-point of the available problem solving time. Overall our data support a special-process theory of insight, whilst also pointing to the role of moderator variables (e.g., available time for solution) in determining the presence or absence of effects predicted by the special-process account

Visual information search in simulated junction negotiation: Gaze transitions of young novice, young experienced and older experienced drivers.

Older drivers and young novice drivers have problems negotiating road junctions and this is reflected in the accident statistics for these driver populations. Explanations for problems with junction negotiation largely focus on limitations in visual information processing and observation errors associated with age and experience. Investigations of drivers viewing behaviour have used measures of fixation and gaze frequency and duration to highlight drivers information processing and search, capacity and requirements. The use of more specific measures of search strategy, such as gaze transitions, has been less common, particularly for the task of gap selection in junction negotiation. Gaze transitions provide information on the positional relationship of fixations, providing a useful tool for highlighting gaps in driver’s visual information acquisition strategies. The gaze transitions of three driver groups (young novice, young experienced and older experienced) were compared during gap selection in right turn junction negotiation manoeuvres. When scanning the junction, young experienced drivers distributed their gaze more evenly across all areas, whereas older and novice drivers made more sweeping transitions, bypassing adjacent areas. The use of a preview strategy in the decision phase was less evident in the older experienced group compared to the younger groups. It is suggested that response preparation requirements of the decision phase impact on older drivers’ ability to maintain a preview strategy. The application of results to driver training interventions and future research are discussed

False memory guided eye movements::insights from a DRM-Saccade paradigm

The Deese-Roediger and McDermott (DRM) paradigm and visually guided saccade tasks are both prominent research tools in their own right. This study introduces a novel DRM-Saccade paradigm, merging both methodologies. We used rule-based saccadic eye movements whereby participants were presented with items at test and were asked to make a saccade to the left or right of the item to denote a recognition or non-recognition decision. We measured old/new recognition decisions and saccadic latencies. Experiment 1 used a pro/anti saccade task to a single target. We found slower saccadic latencies for correct rejection of critical lures, but no latency difference between correct recognition of studied items and false recognition of critical lures. Experiment 2 used a two-target saccade task and also measured corrective saccades. Findings corroborated those from Experiment 1. Participants adjusted their initial decisions to increase accurate recognition of studied items and rejection of unrelated lures but there were no such corrections for critical lures. We argue that rapid saccades indicate cognitive processing driven by familiarity thresholds. These occur before slower source-monitoring is able to process any conflict. The DRM-saccade task could effectively track real-time cognitive resource use during recognition decisions

Stereotype threat may not impact women's inhibitory control or mathematical performance: Providing support for the null hypothesis

Underpinned by the findings of Jamieson and Harkins (2007; Experiment 3), the current study pits the mere effort motivational account of stereotype threat against a working memory interference account. In Experiment 1, females were primed with a negative self- or group stereotype pertaining to their visuospatial ability and completed an anti-saccade eye-tracking task. In Experiment 2 they were primed with a negative or positive group stereotype and completed an anti-saccade and mental arithmetic task. Findings indicate that stereotype threat did not significantly impair women's inhibitory control (Experiments 1 and 2) or mathematical performance (Experiment 2), with Bayesian analyses providing support for the null hypothesis. These findings are discussed in relation to potential moderating factors of stereotype threat, such as task difficulty and stereotype endorsement, as well as the possibility that effect sizes reported in the stereotype threat literature are inflated due to publication bias

How many cues does it take to find every cancer?

Understanding how observers interpret complex medical images and detect pathology is important as errors have serious health and economic implications. Visual search in this applied setting is typically compared between experts and novices to establish what processes experts optimise for high performance, e.g., more efficient eye movements (Donovan & Litchfield, 2013) or exploiting the first glimpse of the scene (Litchfield & Donovan 2016). Yet despite extensive training, experts still miss cancers (4-30%) and rarely achieve 100% cancer detection in experiments. Taking a novel experimental approach, novices were provided with increasing number of cues to establish what it would take to achieve 100% cancer detection. A key factor when finding 'lung nodules' in chest x-rays is that these targets have a variety of shapes and sizes, and their features can be mistaken for normal anatomy. Specifying the target-template so observers know what features precisely to find in images should increase performance, as should presenting this cue in the context of the image. Without cues novice accuracy is typically 50% whereas experts achieve 80%-90% (Donovan & Litchfield, 2013). Presenting 30 novices the precise visual depiction of cancer on 36 images (using a 1-pixel cropped border of the target) yielded 65% accuracy (1 novice achieved 100%). A separate group of 30 novices shown the target cue with a 100-pixel border (including surrounding spatial information), yielded 86% accuracy (and 4 achieved 100%). We discuss how observers make use of these cues and why cancer is still hard to find even when shown onscreen

False memory-guided eye movements: insights from a DRM-Saccade paradigm

The Deese-Roediger and McDermott (DRM) paradigm and visually guided saccade tasks are both prominent research tools in their own right. This study introduces a novel DRM-Saccade paradigm, merging both methodologies. We used rule-based saccadic eye movements whereby participants were presented with items at test and were asked to make a saccade to the left or right of the item to denote a recognition or non-recognition decision. We measured old/new recognition decisions and saccadic latencies. Experiment 1 used a pro/anti saccade task to a single target. We found slower saccadic latencies for correct rejection of critical lures, but no latency difference between correct recognition of studied items and false recognition of critical lures. Experiment 2 used a two-target saccade task and also measured corrective saccades. Findings corroborated those from Experiment 1. Participants adjusted their initial decisions to increase accurate recognition of studied items and rejection of unrelated lures but there were no such corrections for critical lures. We argue that rapid saccades indicate cognitive processing driven by familiarity thresholds. These occur before slower source-monitoring is able to process any conflict. The DRM-Saccade task could effectively track real-time cognitive resource use during recognition decisions