Double reading of chest x-rays is often used to ensure that fewer abnormalities are missed, but very little is known about how the search behavior of others affects observer performance. A series of experiments investigated whether radiographers benefit from knowing where another person looked for pulmonary nodules, and whether the expertise of the model providing the search behavior was a contributing factor. Experiment 1 compared the diagnostic performance of novice and experienced radiographers examining chest x-rays and found that both groups performed better when shown the search behavior of either a novice radiographer or an expert radiologist. Experiment 2 established that benefits in performance only arose when the eye movements shown were related to the search for nodules; however, only the novices' diagnostic performance consistently improved when shown the expert's search behavior. Experiment 3 reexamined the contribution of task, image, and the expertise of the model underlying this benefit. Consistent with Experiment 1, novice radiographers were better at identifying nodules when shown either a naı ¨ve's search behavior or an expert radiologist's search behavior, but they demonstrated no improvement when shown a naı ¨ve model not searching for nodules. Our results suggest that although the benefits of this form of attentional guidance may be short-lived, novices can scaffold their decisions based on the search behavior of others.

Any item and its associated metadata held in the University of Cumbria's institutional repository Insight (unless stated otherwise on the metadata record) may be copied, displayed or performed, and stored in line with the JISC fair dealing guidelines (available here) for educational and notforprofit activities provided that• the authors, title and full bibliographic details of the item are cited clearly when any part of the work is referred to verbally or in the written form• a hyperlink/URL to the original Insight record of that item is included in any citations of the work • the content is not changed in any way• all files required for usage of the item are kept together with the main item file. You may not• sell any part of an item• refer to any part of an item without citation • amend any item or contextualise it in a way that will impugn the creator's reputation• remove or alter the copyright statement on an item.The full policy can be found here. Alternatively contact the University of Cumbria Repository Editor by emailing insight@cumbria.ac.uk.Visual Scanning Behaviour -1 - AbstractWe 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 eyetracking metric time-to-first hit showed systematic decreases across expertise levels in medical image perception. Observers with a range of medical expertise undertook a freeresponse nodule detection task and decision-making improved with expertise, however, the time-to-first fixate a nodule showed only a non-significant trend to decrease with expertise.Surprisingly, naïve and expert observers both allocated less visual attention at nodule locations compared to 1 st and 3 rd 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 than experts to fixate and make errors on distracter regions. Time-to-first hit has been linked to expert performance in mammography, but in chest x-ray inspection, this metric was not sufficiently sensitive to demonstrate clear linear improvements across expertise groups. This brings into question the use of this stand-alone metric as an indirect measure of rapid initial holistic processing.

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 viewed a 250-ms 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 of abnormalities from different medical images. Rather than maximizing 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.

Research has shown that implicitly guiding attention via visual cues or unrelated tasks can increase the likelihood of solving insight problems. We examined whether following another person making specific skin-crossing saccades could induce similar attentional shifts and increase solution rates for Duncker's ((1945)) radiation problem. We presented 150 participants with one of three 30-s eye movement patterns from another problem solver: (a) focusing solely on the central tumour; (b) naturally making skin-crossing saccades between the outside area and the tumour from multiple angles; or (c) making deliberate skin-crossing saccades between the outside area and the tumour from multiple angles. Following another person making skin-crossing saccades increased the likelihood of solving the radiation problem. Our results demonstrate that another person's eye movements can promote attentional shifts that trigger insight problem solving.