Shuffling your way out of change blindness

Listening to trees in the forest: Attentional set influences how semantic and acoustic factors interact in auditory perception

Studies of auditory object perception claim that semantic properties dominate acoustic properties in determining identification accuracy. Yet the direction of the semantic effect is mixed, with some studies showing an advantage for detecting incongruent sounds and others reporting a congruent sound advantage. Here we examine the role of the participant's attentional set when identifying auditory objects in naturalistic soundscapes. We varied the acoustic and semantic properties of the sounds orthogonally in two experiments. In Experiment 1 participants tuned their attention broadly to detect any change between two successive soundscapes (e.g., two restaurant soundscapes, with and without a child coughing). In Experiment 2 they tuned attention more narrowly to a probe presented after a soundscape (e.g., a restaurant soundscape with a child coughing, followed by the coughing sound alone). In both experiments, semantic relations between the objects and backgrounds helped to disambiguate objects that blended acoustically with the background. When attending globally (Experiment 1), objects that were acoustically similar yet semantically incongruent tended to be missed (e.g., bouncing basketball on a construction site), as though camouflaged by the gist of the soundscape. When attending locally (Experiment 2), semantically congruent foil objects led to false positive reports under acoustically similar conditions (hammering sounds on a construction site), as though the gist of the soundscape contributed to their plausible inclusion. In summary, although attentional set had a strong influence on the specific kinds of errors made, both results pointed to participants using a semantically congruent high-level schema to report the sounds they heard.

Binocular fusion enhances the efficiency of spot-the-difference gameplay

Spot-the-difference, the popular childhood game and a prototypical change blindness task, involves identification of differences in local features of two otherwise identical scenes using an eye scanning and matching strategy. Through binocular fusion of the companion scenes, the game becomes a visual search task, wherein players can simply scan the cyclopean percept for local features that may distinctly stand-out due to binocular rivalry/lustre. Here, we had a total of 100 visually normal adult (18-28 years of age) volunteers play this game in the traditional non-fusion mode and after cross-fusion of the companion images using a hand-held mirror stereoscope. The results demonstrate that the fusion mode significantly speeds up gameplay and reduces errors, relative to the non-fusion mode, for a range of target sizes, contrasts, and chromaticity tested (all, p<0.001). Amongst the three types of local feature differences available in these images (polarity difference, presence/absence of a local feature difference and shape difference in a local feature difference), features containing polarity difference was identified as first in ~60-70% of instances in both modes of gameplay (p<0.01), with this proportion being larger in the fusion than in the non-fusion mode. The binocular fusion advantage is lost when the lustre cue is purposefully weakened through alterations in target luminance polarity. The spot-the-difference game may thus be cheated using binocular fusion and the differences readily identified through a vivid experience of binocular rivalry/lustre.

Changing in a GIF (Graphics Interchange Format): Innovations in Before and After Photography

PURPOSE

Before and after images are an important part of aesthetic counseling, but no studies have examined ways to optimize change detection through the layout of displayed images. This study compares 3 different image layouts to determine which presentation style improves perception of postprocedure changes.

METHODS

In this prospective, randomized study, participants viewed sequential images of patients who either had or had not undergone upper eyelid blepharoptosis repair or blepharoplasty ("change" and "no-change," respectively). These paired images were randomly presented in 1 of 3 formats: side-by-side, up-and-down, or alternation flicker (in which 2 images are superimposed and alternated in a graphics interchange format). Participants were asked if a procedure had been performed based on the 2 photographs. Paired t tests were used to compare response times and change detection rates between individual-level pairs of presentation modes.

RESULTS

Of 299 recruited patients, 286 completed the study. Rate of change detection trended toward increased sensitivity for alternation flicker over static images. This became statistically significant for patients less than 45 years old. Detection rates did not differ significantly between the 2 static layouts (side-by-side and up-and down).

CONCLUSIONS

Enhancing and customizing aesthetics counseling for different ages can improve patient understanding, expectations, and advertising. When using static photography, the layout, whether side-by-side or up-and-down, can be chosen to fit the mode of presentation with no statistically significant difference. To optimize detection of changes in before and after photography in a demographic less than 45 years old, the animated, alternation flicker format was statistically significantly more effective.

Let's Use Cognitive Science to Create Collaborative Workstations

When informed by an understanding of cognitive science, radiologists' workstations could become collaborative to improve radiologists' performance and job satisfaction. The authors review relevant literature and present several promising areas of research, including image toggling, eye tracking, cognitive computing, intelligently restricted messaging, work habit tracking, and innovative input devices. The authors call for more research in "perceptual design," a promising field that can complement advances in computer-aided detection.

Image toggling saves time in mammography

When two images are perfectly aligned, even subtle differences are readily detected when the images are "toggled" back and forth in the same location. However, substantial changes between two photographs can be missed if the images are misaligned ("change blindness"). Nevertheless, recent work from our lab, testing nonradiologists, suggests that toggling misaligned photographs leads to superior performance compared to side-by-side viewing (SBS). In order to determine if a benefit of toggling misaligned images may be observed in clinical mammography, we developed an image toggling technique where pairs of new and prior breast imaging exam images could be efficiently toggled back and forth. Twenty-three radiologists read 10 mammograms evenly divided in toggle and SBS modes. The toggle mode led to a 6-s benefit in reaching a decision [[Formula: see text], [Formula: see text]]. The toggle viewing mode also led to a 5% improvement in diagnostic accuracy, though in our small sample this effect was not statistically reliable. Time savings were found even though successive mammograms were not perfectly aligned. Given the ever-increasing caseload for radiologists, this simple manipulation of how the images are viewed could save valuable time in clinical practice, allowing radiologists to read more cases or spend more time on difficult cases.