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As the first step in image interpretation is detection, an error in perception can prematurely end the diagnostic process leading to missed diagnoses. Because perceptual errors of this sort-"failure to detect"-are the most common interpretive error (and cause of litigation) in radiology, understanding the nature of perceptual expertise is essential in decreasing radiology's long-standing error rates. In this article, we review what constitutes a perceptual error, the existing models of radiologic image perception, the development of perceptual expertise and how it can be tested, perceptual learning methods in training radiologists, and why understanding perceptual expertise is still relevant in the era of artificial intelligence. Adding targeted interventions, such as perceptual learning, to existing teaching practices, has the potential to enhance expertise and reduce medical error. [ABSTRACT FROM AUTHOR]

Visual search is the task of finding things with uncertain locations. Despite decades of research, the features that guide visual search remain poorly specified, especially in realistic contexts. This study tested the role of two features--shape and orientation-- both in the presence and absence of hue information. We conducted five experiments to describe preview-target mismatch effects, decreases in performance caused by differences between the image of the target as it appears in the preview and as it appears in the actual search display. These mismatch effects provide direct measures of feature importance, with larger performance decrements expected for more important features. Contrary to previous conclusions, our data suggest that shape and orientation only guide visual search when color is not available. By varying the probability of mismatch in each feature dimension, we also show that these patterns of feature guidance do not change with the probability that the previewed feature will be invalid. We conclude that the target representations used to guide visual search are much less precise than previously believed, with participants encoding and using color and little else. [ABSTRACT FROM AUTHOR]

Radiologists rely principally on visual inspection to detect, describe, and classify findings in medical images. As most interpretive errors in radiology are perceptual in nature, understanding the path to radiologic expertise during image analysis is essential to educate future generations of radiologists. We review the perceptual tasks and challenges in radiologic diagnosis, discuss models of radiologic image perception, consider the application of perceptual learning methods in medical training, and suggest a new approach to understanding perceptional expertise. Specific principled enhancements to educational practices in radiology promise to deepen perceptual expertise among radiologists with the goal of improving training and reducing medical error. [ABSTRACT FROM AUTHOR]

Prior target knowledge (i.e., positive cues) improves visual search performance. However, there is considerable debate about whether distractor knowledge (i.e., negative cues) can guide search. Some studies suggest the active suppression of negatively cued search items, while others suggest the initial capture of attention by negatively cued items. Prior work has used pictorial or specific text cues but has not explicitly compared them. We build on that work by comparing positive and negative cues presented pictorially and as categorical text labels using photorealistic objects and eye movement measures. Search displays contained a target (cued on positive trials), a lure from the target category (cued on negative trials), and four categorically-unrelated distractors. Search performance with positive cues resulted in stronger attentional guidance and faster object recognition for pictorial relative to categorical cues (i.e., a pictorial advantage, suggesting specific visual details afforded by pictorial cues improved search). However, in most search performance metrics, negative cues mitigate the pictorial advantage. Given that the negatively cued items captured attention, generated target guidance but mitigated the pictorial advantage, these results are partly consistent with both existing theories. Specific visual details provided in positive cues produce a large pictorial advantage in all measures, whereas specific visual details in negative cues only produce a small pictorial advantage for object recognition but not for attentional guidance. This asymmetry in the pictorial advantage suggests that the down-weighting of specific negatively cued visual features is less efficient than the up-weighting of specific positively cued visual features. [ABSTRACT FROM AUTHOR]

There is growing evidence that the statistical properties of ensembles of similar objects are processed in a qualitatively different manner than the characteristics of individual items. It has recently been proposed that these types of perceptual statistical representations are part of a strategy to complement focused attention in order to circumvent the visual system's limited capacity to represent more than a few individual objects in detail. Previous studies have demonstrated that patients with attentional deficits are nonetheless sensitive to these sorts of statistical representations. Here, we examined how such global representations may function to aid patients in overcoming focal attentional limitations by manipulating the statistical regularity of a visual scene while patients performed a search task. Three patients previously diagnosed with visual neglect searched for a target Gabor tilted to the left or right of vertical in displays of horizontal distractor Gabors. Although the local sizes of the distractors changed on every trial, the mean size remained stable for several trials. Patients made faster correct responses to targets in neglected regions of the visual field when global statistics remained constant over several trials, similar to age-matched controls. Given neglect patients' attentional deficits, these results suggest that stable perceptual representations of global statistics can establish a context to speed search without the need to represent individual elements in detail. [ABSTRACT FROM AUTHOR]

Abstract: Do the target–distractor and distractor–distractor similarity relationships known to exist for simple stimuli extend to real-world objects, and are these effects expressed in search guidance or target verification? Parts of photorealistic distractors were replaced with target parts to create four levels of target–distractor similarity under heterogenous and homogenous conditions. We found that increasing target–distractor similarity and decreasing distractor–distractor similarity impaired search guidance and target verification, but that target–distractor similarity and heterogeneity/homogeneity interacted only in measures of guidance; distractor homogeneity lessens effects of target–distractor similarity by causing gaze to fixate the target sooner, not by speeding target detection following its fixation. [Copyright &y& Elsevier]