Disentangling the effects of spatial inconsistency of targets and distractors when searching in realistic scenes (original) (raw)

Is attention necessary for object identification? Evidence from eye movements during the inspection of real-world scenes

Consciousness and Cognition, 2008

Eye movements were recorded during the display of two images of a real-world scene that were inspected to determine whether they were the same or not (a comparative visual search task). In the displays where the pictures were different, one object had been changed, and this object was sometimes taken from another scene and was incongruent with the gist. The experiment established that incongruous objects attract eye fixations earlier than the congruous counterparts, but that this effect is not apparent until the picture has been displayed for several seconds. By controlling the visual saliency of the objects the experiment eliminates the possibility that the incongruency effect is dependent upon the conspicuity of the changed objects. A model of scene perception is suggested whereby attention is unnecessary for the partial recognition of an object that delivers sufficient information about its visual characteristics for the viewer to know that the object is improbable in that particular scene, and in which full identification requires foveal inspection.

The roles of scene priming and location priming in object-scene consistency effects

Frontiers in Psychology, 2014

Presenting consistent objects in scenes facilitates object recognition as compared to inconsistent objects. Yet the mechanisms by which scenes influence object recognition are still not understood. According to one theory, consistent scenes facilitate visual search for objects at expected places. Here, we investigated two predictions following from this theory: If visual search is responsible for consistency effects, consistency effects could be weaker (1) with better-primed than less-primed object locations, and (2) with less-primed than better-primed scenes. In Experiments 1 and 2, locations of objects were varied within a scene to a different degree (one, two, or four possible locations). In addition, object-scene consistency was studied as a function of progressive numbers of repetitions of the backgrounds. Because repeating locations and backgrounds could facilitate visual search for objects, these repetitions might alter the object-scene consistency effect by lowering of location uncertainty. Although we find evidence for a significant consistency effect, we find no clear support for impacts of scene priming or location priming on the size of the consistency effect. Additionally, we find evidence that the consistency effect is dependent on the eccentricity of the target objects. These results point to only small influences of priming to object-scene consistency effects but all-in-all the findings can be reconciled with a visual-search explanation of the consistency effect.

Scene incongruity and attention

Does scene incongruity, (a mismatch between scene gist and a semantically incongruent object), capture attention and lead to conscious perception? We explored this question using 4 different procedures: Inattention (Experiment 1), Scene description (Experiment 2), Change detection (Experiment 3), and Iconic Memory (Experiment 4). We found no differences between scene incongruity and scene congruity in Experiments 1, 2, and 4, although in Experiment 3 change detection was faster for scenes containing an incongruent object. We offer an explanation for why the change detection results differ from the results of the other three experiments. In all four experiments, participants invariably failed to report the incongruity and routinely mis-described it by normalizing the incongruent object. None of the results supports the claim that semantic incongruity within a scene invariably captures attention and provide strong evidence of the dominant role of scene gist in determining what is perceived.

Anchoring visual search in scenes: Assessing the role of anchor objects on eye movements during visual search

Journal of Vision, 2018

The arrangement of the contents of real-world scenes follows certain spatial rules that allow for extremely efficient visual exploration. What remains underexplored is the role different types of objects hold in a scene. In the current work, we seek to unveil an important building block of scenes-anchor objects. Anchors hold specific spatial predictions regarding the likely position of other objects in an environment. In a series of three eye tracking experiments we tested what role anchor objects occupy during visual search. In all of the experiments, participants searched through scenes for an object that was cued in the beginning of each trial. Critically, in half of the scenes a target relevant anchor was swapped for an irrelevant, albeit semantically consistent, object. We found that relevant anchor objects can guide visual search leading to faster reaction times, less scene coverage, and less time between fixating the anchor and the target. The choice of anchor objects was confirmed through an independent large image database, which allowed us to identify key attributes of anchors. Anchor objects seem to play a unique role in the spatial layout of scenes and need to be considered for understanding the efficiency of visual search in realistic stimuli.

Does consistent scene context facilitate object perception?

Journal of Experimental Psychology-general, 1998

The conclusion that scene knowledge interacts with object perception depends on evidence that object detection is facilitated by consistent scene context. Experiment 1 replicated the I. Biederman, R. J. Mezzanotte, and J. C. Rabinowitz (1982) object-detection paradigm. Detection performance was higher for semantically consistent versus inconsistent objects. However, when the paradigm was modified to control for response bias (Experiments 2 and 3) or when response bias was eliminated by means of a forced-choice procedure (Experiment 4), no such advantage obtained. When an additional source of biasing information was eliminated by presenting the object label after the scene (Experiments 3 and 4), there was either no effect of consistency (Experiment 4) or an inconsistent object advantage (Experiment 3). These results suggest that object perception is not facilitated by consistent scene context.

How context information and target information guide the eyes from the first epoch of search in real-world scenes

Journal of Vision, 2014

This study investigated how the visual system utilizes context and task information during the different phases of a visual search task. The specificity of the target template (the picture or the name of the target) and the plausibility of target position in real-world scenes were manipulated orthogonally. Our findings showed that both target template information and guidance of spatial context are utilized to guide eye movements from the beginning of scene inspection. In both search initiation and subsequent scene scanning, the availability of a specific visual template was particularly useful when the spatial context of the scene was misleading and the availability of a reliable scene context facilitated search mainly when the template was abstract. Target verification was affected principally by the level of detail of target template, and was quicker in the case of a picture cue. The results indicate that the visual system can utilize target template guidance and context guidance flexibly from the beginning of scene inspection, depending upon the amount and the quality of the available information supplied by either of these highlevel sources. This allows for optimization of oculomotor behavior throughout the different phases of search within a real-world scene.

The influence of scene context on object recognition is independent of attentional focus

Frontiers in Psychology, 2013

Humans can quickly and accurately recognize objects within briefly presented natural scenes. Previous work has provided evidence that scene context contributes to this process, demonstrating improved naming of objects that were presented in semantically consistent scenes (e.g., a sandcastle on a beach) relative to semantically inconsistent scenes (e.g., a sandcastle on a football field). The current study was aimed at investigating which processes underlie the scene consistency effect. Specifically, we tested: (1) whether the effect is due to increased visual feature and/or shape overlap for consistent relative to inconsistent scene-object pairs; and (2) whether the effect is mediated by attention to the background scene. Experiment 1 replicated the scene consistency effect of a previous report . Using a new, carefully controlled stimulus set, Experiment 2 showed that the scene consistency effect could not be explained by lowlevel feature or shape overlap between scenes and target objects. Experiments 3a and 3b investigated whether focused attention modulates the scene consistency effect. By using a location cueing manipulation, participants were correctly informed about the location of the target object on a proportion of trials, allowing focused attention to be deployed toward the target object. Importantly, the effect of scene consistency on target object recognition was independent of spatial attention, and was observed both when attention was focused on the target object and when attention was focused on the background scene. These results indicate that a semantically consistent scene context benefits object recognition independently of the focus of attention. We suggest that the scene consistency effect is primarily driven by global scene properties, or "scene gist" , that can be processed with minimal attentional resources.

Cat and mouse search: the influence of scene and object analysis on eye movements when targets change locations during search

Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 2017

We explored the influence of early scene analysis and visible object characteristics on eye movements when searching for objects in photographs of scenes. On each trial, participants were shown sequentially either a scene preview or a uniform grey screen (250 ms), a visual mask, the name of the target and the scene, now including the target at a likely location. During the participant's first saccade during search, the target location was changed to: (i) a different likely location, (ii) an unlikely but possible location or (iii) a very implausible location. The results showed that the first saccade landed more often on the likely location in which the target re-appeared than on unlikely or implausible locations, and overall the first saccade landed nearer the first target location with a preview than without. Hence, rapid scene analysis influenced initial eye movement planning, but availability of the target rapidly modified that plan. After the target moved, it was found more ...