Mental layout extrapolations prime spatial processing of scenes

Four experiments examined whether scene processing is facilitated by layout representation, including layout that was not perceived but could be predicted based on a previous partial view (boundary extension). In a priming paradigm (after Sanocki, 2003), participants judged objects' distances in photographs. In Experiment 1, full scenes (target), partial scenes, and two control primes were used. Partial scenes excluded the target objects' locations, but these areas could be predicted. Full and partial scenes produced equal performance facilitation. In Experiment 2, task-irrelevant partial scene primes were also tested. These primes did not facilitate performance (i.e. simple scene previews did not help). Experiment 3 showed that a partial prime's utility depended on the area of the scene that would be tested; the task-irrelevant primes used in Experiment 2 were useful for other distance judgments. Experiment 4 showed that partial scene facilitation is not limited to the area immediately surrounding the prime. The study demonstrated that perceived and mentally extrapolated layouts are equally effective.     

Object recognition in dense clutter

Observers in recognition experiments invariably view objects against a blank background, whereas observers of real scenes sometimes view objects against dense clutter. In this study, we examined whether an object's background affects the information used for recognition. Our stimuli consisted of color photographs of everyday objects. The photographs were organized either as a sparse array, as is typical of a visual search experiment, or as high density clutter, such as might be found in a toy chest, a handbag, or a kitchen drawer. The observer's task was to locate an animal, vehicle, or food target in the stimulus. We varied the information in the stimuli by convolving them with a low-pass filter (blur) or a high-pass filter (edge) or converting them to grayscale. In two experiments, we found that the blur and edge manipulations produced a modest decrement in performance with the sparse arrangement but a severe decrement in performance with the clutter arrangement. These results indicate that the information used for recognition depends on the object's background. Thus, models of recognition that have been developed for isolated objects may not generalize to objects in dense clutter.     

Incidental visual memory for objects in scenes

Three experiments were conducted to investigate the existence of incidentally acquired, long-term, detailed visual memory for objects embedded in previously viewed scenes. Participants performed intentional memorization and incidental visual search learning tasks while viewing photographs of real-world scenes. A visual memory test for previously viewed objects from these scenes then followed. Participants were not aware that they would be tested on the scenes following incidental learning in the visual search task. In two types of memory tests for visually specific object information (token discrimination and mirror-image discrimination), performance following both the memorization and visual search conditions was reliably above chance. These results indicate that recent demonstrations of good visual memory during scene viewing are not due to intentional scene memorization. Instead, long-term visual representations are incidentally generated as a natural product of scene perception.     

Perceptual expertise improves category detection in natural scenes

There is much debate about how detection, categorization, and within-category identification relate to one another during object recognition. Whether these tasks rely on partially shared perceptual mechanisms may be determined by testing whether training on one of these tasks facilitates performance on another. In the present study we asked whether expertise in discriminating objects improves the detection of these objects in naturalistic scenes. Self-proclaimed car experts (N = 34) performed a car discrimination task to establish their level of expertise, followed by a visual search task where they were asked to detect cars and people in hundreds of photographs of natural scenes. Results revealed that expertise in discriminating cars was strongly correlated with car detection accuracy. This effect was specific to objects of expertise, as there was no influence of car expertise on person detection. These results indicate a close link between object discrimination and object detection performance, which we interpret as reflecting partially shared perceptual mechanisms and neural representations underlying these tasks: the increased sensitivity of the visual system for objects of expertise – as a result of extensive discrimination training – may benefit both the discrimination and the detection of these objects. Alternative interpretations are also discussed.     

Memory for modality of presentation: Within-modality discrimination

Two experiments demonstrated that Ss are capable of making within-modality memory discriminations in both visual and auditory modalities. In Experiment I Ss studied mixed lists of pictures and labels representing common objects and were subsequently required to judge whether the original presentation was pictorial or verbal The high level of performance achieved on this task was unaffected by degree of categorical relatedness of items within method of presentation or by instructions to produce visual images when items were presented verbally. In Experiment II Ss demonstrated the ability to remember whether a sentence was originally presented by a male or a female speaker. Some strategies by which within-modality discrimination in memory might be accomplished are discussed.     

靶刺激变换与情景信息属性对真实情景再认的影响

采用眼动研究范式,通过两个实验考察靶刺激变换与情景信息属性对情景再认的影响。实验一结果显示,靶刺激变换对情景再认、靶刺激所属兴趣区的凝视时间均有显著影响,这表明在情景再认过程中,观察者会有意识地搜索靶刺激,靶刺激具有诊断效应;实验二应用了知觉信息与语义信息重合和分离两种情景材料。结果显示,观察者对语义信息的首次注视次数显著多于知觉信息;观察者对知觉信息和语义信息分离条件下语义信息的首次注视时间显著长于重合条件下。这一结果提示,在情景识别过程中,语义信息具有注意优先性,但其优先性会受到知觉信息启动的干扰。     

Persistent effects of information about internal reactions: Ineffectiveness of debriefing

A process of self-persuasion has been advanced to account for the effects of information about internal reactions on attitudes toward emotional stimuli. To determine whether the results of this cognitive activity would be resistant to debriefing, Ss were shown slides of female nudes while hearing their alleged heart-rate reactions and were subsequently informed that these reactions were part of a deception manipulation. It was found that, although Ss accepted the debriefing, the false information continued to exert an infleunce on their attitudes toward the nudes. The attitudes of these Ss toward the nudes were the same as those of Ss who were not debriefed.     

Persistent Effects of Information about Internal Reactions: Ineffectiveness of Debriefing

A process of self-persuasion has been advanced to account for the effects of information about internal reactions on attitudes toward emotional stimuli. To determine whether the results of this cognitive activity would be resistant to debriefing, Ss were shown slides of female nudes while hearing their alleged heart-rate reactions and were subsequently informed that these reactions were part of a deception manipulation. It was found that, although Ss accepted the debriefing, the false information continued to exert an influence on their attitudes toward the nudes. The attitudes of these Ss toward the nudes were the same as those of Ss who were not debriefed.     

The relationship between cognitive,motor-kinesthetic,and oculomotor adaptation

The literature concerning adaptation to prism indicates that several adaptive mechanisms may be important. The particular mechanism or mechanisms involved depends (at least in part) upon the type of adaptive exposure. In the present study. three adaptive mechanisms (cognitive. oculomotor, and motor-kinesthetic) were investigated. Ss were asked to point in the dark at an illuminated target. The target was seen displaced from its veridical position due to a wedge prism placed before S’s right eye. The left eye was occluded. Ss then viewed their visual target pointing errors through the displacing prism without seeing any part of their bodies. One group of Ss was instructed to ignore these prism-induced errors and to continue pointing at the target’s visual position. A second group of Ss was instructed to compensate fully for their errors and to at tempt to eliminate them on all future trials. For the latter group errors were completely eliminated, while for Ss instructed to ignore their errors, relatively small improvement in visual target settings occurred. This improvement was called cognitive adaptation, since it depended on the S’s conscious control. In addition. for both conditions. evidence was found that allowing Ss to view their prism-induced pointing errors resulted in some form of motor-kinesthetic adaptation. This adaptation was hypothesized to represent a change in the judged position of the pointing hand relative to its felt position. It was concluded that this motor-kinesthetic adaptation was dependent, in part, upon cognitive information concerning the effects of the prism and that it serves to reduce conflict between cognitive and visual cues, i.e., between what S believes and what he sees.     

Stimulus complexity,free looking time,and inspective exploration

Fourteen Ss rated 59 objects on a seven point complexity scale. From these ratings 10 objects were chosen at the high, middle, and low levels of complexity, and 35 mm slides were made of these 30 objects. Fifteen Ss manipulated and inspected each of the objects for as long as they wished and a second group of 15 Ss viewed slides of the objects for as long as they wished. Analysis of the time scores from these two groups revealed that both inspective manipulation time and free looking time increased as a function of stimulus complexity. Inspective manipulation time was greater than free looking time except at the low complexity level.     

Threats,Promises, and Coalitions: A Study of Compliance and Retaliation in a Simulated Organizational Setting1

This research sought to examine the effects of threats and promises on compliance and the formation of subordinate coalitions in a simulated employeremployee conflict situation. It also sought to determine some of the motives underlying coalition decisions-tangible and intangible-and the conditions under which each of these possible motive types would be salient. Coalition motives were examined by manipulating the consequences for coalition members following their use of coalition power (presence vs. absence of monetary gain). A control condition was present in which no such power was available. Ninety male undergraduate business students were randomly assigned to one of six experimental conditions in a 3 × 2 factorial design. Three Ss engaged in a modified bilateral monopoly bargaining task in which two of them (the “employees”) believed they were exchanging a series of offers and counteroffers with the third (the “employer”) over a hypothetical wage increase for a maximum of eight rounds. Ss were told they would earn a sum of money proportional to the effectiveness of their bargaining. In actuality, all Ss were assigned the employee role and all employer “offers” were pre-programmed. On round six, the Ss were “sent” either a threat or promise message by the employer demanding that they accept his round five offer. Compliance-noncompliance was defined as employee acceptance-rejection of this demand, respectively. In addition to compliance behavior, S s in coalition conditions had the power to form an alliance with the other employee against the employer after the latter used his threat or promise power. Coalitions could confiscate up to 25% of the employer's earnings and, depending on experimental condition, could either keep or not keep any money their coalition acquired. It was hypothesized that threateners would elicit less compliance, and be responded to with more, and more severe subordinate coalitions than would promisers. It was further assumed that there would be less compliance when subordinates had coalition power, and that the effect of monetary reward on the likelihood of coalition formation would be contingent on the type of power (threats vs. promises) the employer used. Specifically, it was assumed that a majority of S s in the Threat condition who had this power would form coalitions against the employer regardless of whether or not they realized any tangible gain for doing so. In the promise condition, however, it was expected that coalition decisions would be based primarily on whether Ss stood to gain monetarily. The hypotheses were supported. These results were discussed in terms of the impact of power acquisition as a variable mediating perception and compliance behavior, and in terms of the role of economic vs. retaliatory motives as factors underlying subordinate coalition decisions. Some of the conditions which influence the relative salience of these two coalition motives were proposed, and the organizational implications of these findings were suggested.     

Core geometry in perspective

Research on animals, infants, children, and adults provides evidence that distinct cognitive systems underlie navigation and object recognition. Here we examine whether and how these systems interact when children interpret 2D edge‐based perspectival line drawings of scenes and objects. Such drawings serve as symbols early in development, and they preserve scene and object geometry from canonical points of view. Young children show limits when using geometry both in non‐symbolic tasks and in symbolic map tasks that present 3D contexts from unusual, unfamiliar points of view. When presented with the familiar viewpoints in perspectival line drawings, however, do children engage more integrated geometric representations? In three experiments, children successfully interpreted line drawings with respect to their depicted scene or object. Nevertheless, children recruited distinct processes when navigating based on the information in these drawings, and these processes depended on the context in which the drawings were presented. These results suggest that children are flexible but limited in using geometric information to form integrated representations of scenes and objects, even when interpreting spatial symbols that are highly familiar and faithful renditions of the visual world.     

On cross-modal similarity: the perceptual structure of pitch, loudness, and brightness

Examined how pitch and loudness correspond to brightness. In the Experiment 1, 16 Ss identified which of 2 lights more resembled each of 16 tones; in Experiment 2, 8 of the same 16 Ss rated the similarity of lights to lights, tones to tones, and lights to tones. (1) Pitch and loudness both contributed to cross-modal similarity, but for most Ss pitch contributed more. (2) Individuals differed as to whether pitch or loudness contributed more; these differences were consistent across matching and similarity scaling. (3) Cross-modal similarity depended largely on relative stimulus values. (4) Multidimensional scaling revealed 2 perceptual dimensions, loudness and pitch, with brightness common to both. A simple quantitative model can describe the cross-modal comparisons, compatible with the view that perceptual similarity may be characterized through a malleable spatial representation that is multimodal as well as multidimensional.     

Color onsets and offsets, and luminance changes can cause change blindness

It has recently been demonstrated that people often fail to detect between-view changes in their visual environment. This phenomenon, called 'change blindness' (CB), occurs whenever the perceptual transient that usually accompanies a change is somehow blocked, or made less salient. In the well-known flicker paradigm, the transient is blocked by inserting a blank screen between the original and changed scenes. We tested whether transients that do not involve the appearance or disappearance of visual objects would also produce CB. Therefore we tested whether the appearance or disappearance of color information, and increments or decrements in luminance, could cause CB. In three experiments, subjects searched for changes in natural scenes. We found that both color transients and luminance transients significantly reduced change detection (by approximately 30%) relative to a no-transient condition.     

Filmed treatment as an effective fear-reduction technique

The present study attempted to determine whether age and sex of a film model would differentially affect fear reduction in the viewing children. The experiment also tested the reactions of Ss to films using real feared objects versus films of simulated objects. Twenty-five fourth- and fifth-grade males who were fearful of snakes were shown a treatment film for a total of 10 minutes. Pretreatment and posttreatment tests included asking Ss to approach and handle a live 4-ft. boa constrictor. Results indicated that models' age and sex characteristics did not influence their effectiveness as behavior-change agents. It was found that the use of the real feared object in the treatment film was a more effective fear reducer than was a replica of the object.This paper is based on research supported in part by National Institute of Child Health and Human Development Grant 03234 to Dr. James Bryan.Thanks are extended to Mr. James Fritts and the many other personnel from District 68 of Skokie, Illinois, who enabled us to perform this experiment.     

Attentional priming releases crowding

Views of natural scenes unfold over time, and objects of interest that were present a moment ago tend to remain present. While visual crowding places a fundamental limit on object recognition in cluttered scenes, most studies of crowding have suffered from the limitation that they typically involved static scenes. The role of temporal continuity in crowding has therefore been unaddressed. We investigated intertrial effects upon crowding in visual scenes, showing that crowding is considerably diminished when objects remain constant on consecutive visual search trials. Repetition of both the target and distractors decreases the critical distance for crowding from flankers. More generally, our results show how object continuity through between-trial priming releases objects that would otherwise be unidentifiable due to crowding. Crowding, although it is a significant bottleneck on object recognition, can be mitigated by statistically likely temporal continuity of the objects. Crowding therefore depends not only on what is momentarily present, but also on what was previously attended.     

Object detection in natural scenes: Independent effects of spatial and category-based attention

Humans are remarkably efficient in detecting highly familiar object categories in natural scenes, with evidence suggesting that such object detection can be performed in the (near) absence of attention. Here we systematically explored the influences of both spatial attention and category-based attention on the accuracy of object detection in natural scenes. Manipulating both types of attention additionally allowed for addressing how these factors interact: whether the requirement for spatial attention depends on the extent to which observers are prepared to detect a specific object category—that is, on category-based attention. The results showed that the detection of targets from one category (animals or vehicles) was better than the detection of targets from two categories (animals and vehicles), demonstrating the beneficial effect of category-based attention. This effect did not depend on the semantic congruency of the target object and the background scene, indicating that observers attended to visual features diagnostic of the foreground target objects from the cued category. Importantly, in three experiments the detection of objects in scenes presented in the periphery was significantly impaired when observers simultaneously performed an attentionally demanding task at fixation, showing that spatial attention affects natural scene perception. In all experiments, the effects of category-based attention and spatial attention on object detection performance were additive rather than interactive. Finally, neither spatial nor category-based attention influenced metacognitive ability for object detection performance. These findings demonstrate that efficient object detection in natural scenes is independently facilitated by spatial and category-based attention.     

Pigeons' recognition of partially occluded objects depends on specific training experience

DiPietro et al (2002 Perception 31 1299-1312) reported a dramatic improvement in pigeons' recognition of partially occluded objects after the birds had been trained to recognize objects that were placed on top of another surface. Here, we investigated whether training with partially erased stimuli or with notched stimuli that had a thin gap between the object and another surface would similarly enhance pigeons' recognition of partially occluded objects. We found that erased training had no effect on the birds' recognition of partially occluded objects. Training pigeons to recognize notched objects improved their performance with the same objects when they were partially occluded; but this improvement did not transfer to novel objects, a result that DiPietro et al reported after on-top training. Together, the present results and those of DiPietro et al implicate prior experience as a key factor in pigeons' recognition of partially occluded objects. Training experiences which improve recognition of partially occluded objects may do so because they improve decomposition of complex two-dimensional scenes by pigeons into separate entities.     

Object appearance,disappearance, and attention prioritization in real-world scenes

We examined the prioritization of abruptly appearing and disappearing objects in real-world scenes. These scene changes occurred either during a fixation (transient appearance/disappearance) or during a saccade (nontransient appearance/disappearance). Prioritization was measured by the eyes’ propensity to be directed to the region of the scene change. Object additions and deletions were fixated at rates greater than chance, suggesting that both types of scene change are cues used by the visual system to guide attention during scene exploration, although appearances were fixated twice as often as disappearances, indicating that new objects are more salient than deleted objects. New and deleted objects were prioritized sooner and more frequently if they occurred during a fixation, as compared with during a saccade, indicating an important role of the transient signal that often accompanies sudden changes in scenes. New objects were prioritized regardless of whether they appeared during a fixation or a saccade, whereas prioritization of a deleted object occurred only if (1) a transient signal was present or (2) the removal of the object revealed previously occluded objects.