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Valuable stimuli receive attentional priority. However, it is unknown whether the mechanism of the attentional priority is based on relative (e.g., higher) or absolute (e.g., 45 points) values. Therefore, we manipulated the relative and absolute values independently in a modified value-driven attentional capture paradigm. In the training phase, where associative learning occurs between color and reward value, two test target colors were each presented with another different target color (reference target colors) in separate context blocks. Therefore, each test target color had different reference points. In the test phase, the two test target colors were used as singleton distractor colors. In the training phase of Experiment 1, the absolute reward value of the test target colors was the same, but one had a higher value than its reference target color and the other had a lower value. In the test phase, the high relative value color distractor captured attention more, suggesting that the relative value of stimuli influenced selective attention. In Experiment 2 the relative value of the test target colors was the same, but the absolute value was higher for one. The high and low absolute value color distractors captured attention equally in the test phase, indicating little impact of the absolute value on selective attention. These findings suggest that the relative value, rather than absolute value, plays a critical role in the allocation of attention. Accordingly, the present study suggests that prospect theory (Kahneman & Tversky, Econometrica, 47 (2), 363-391, 1979) can be extended to earlier cognitive stages such as selective attention.

An interesting set of findings has emerged from the literature regarding schizotypy. Individuals with psychometric schizotypy self-report pathology in certain neuropsychological, affective experiential, expressive and olfactory abilities and subjective quality of life at levels between one and two standard deviations more severe than their non-schizotypal peers; a level often similar to that seen in chronic schizophrenia. Objectively however, individuals with psychometric schizotypy do not show concomitant impairments in these domains. This “subjective-objective” disjunction is remarkable in that samples are largely drawn from college settings; thus likely reflecting the healthiest individuals within the schizophrenia-spectrum. We propose that this disjunction can be conceptualized as a “cognitive bias”, and that it reflects a dysfunction in the systems underlying reasoning and self-evaluation. In this article, we lay out evidence underlying the subjective-objective disjunction and discuss potential methodological and psychological issues that may explain this phenomenon.

Two experiments were conducted to directly test the feature set hypothesis and the relational set hypothesis in an inattentional blindness task. The feature set hypothesis predicts that unexpected objects that match the to-be-attended stimuli will be reported most. The relational set hypothesis predicts that unexpected objects that match the relationship between the to-be-attended and the to-be-ignored stimuli will be reported the most. Experiment 1 manipulated the luminance of the stimuli. Participants were instructed to monitor the gray letter shapes and to ignore either black or white letter shapes. The unexpected objects that exhibited the luminance relation of the to-be-attended to the to-be-ignored stimuli were reported by participants the most. Experiment 2 manipulated the color of the stimuli. Participants were instructed to monitor the yellower orange or the redder orange letter shapes and to ignore the redder orange or yellower letter shapes. The unexpected objects that exhibited the color relation of the to-be-attended to the to-be-ignored stimuli were reported the most. The results do not support the use of a feature set to accomplish the task and instead support the use of a relational set. In addition, the results point to the concurrent use of multiple attentional sets that are both excitatory and inhibitory.

The limited capacity of visual working memory (VWM) can be maximized by combining multiple features into a single representation through grouping principles such as connection, proximity, and similarity. In this study, we sought to understand how VWM organizes information by investigating how connection and similarity cues are used either alone or in the presence of another grouping cue. Furthermore, we examined whether the use of one cue over another is within volitional control. Participants remembered displays of objects that contained no grouping cues, connection cues only, similarity cues only, or both connection and similarity cues. We found that it is possible to use either connection or similarity cues, although connection cues tend to dominate if the cues are in conflict with one another. However, it is possible to flexibly use either similarity or connection cues if both are present, depending on the task goals.

When briefly presented with global and local visual information, individuals report global information more quickly and more accurately than local information, a phenomenon known as the global precedence effect (GPE; Navon, 1977). We investigated whether a bias toward global information persists in visual working memory (VWM) and whether the VWM representations for global and local features include information bound to their hierarchical levels and to each other. Navon figures, in which a larger (global) letter is composed of smaller (local) letters, were presented, and participants performed a change detection task that required participants to remember features only (either a global or local letter changed to a new identity); features bound to their hierarchical levels (the global and local letters within an object swapped levels); or features bound to each other within an object (2 letters from the same level swapped between objects). Performance suggested that there was a GPE in VWM (new global letters were more accurately detected than new local letters) and that although global and local features were not necessarily bound together in VWM, they were bound to their corresponding hierarchical levels. These results indicate that level binding in VWM occurs more readily than binding specific object features together. These findings further our understanding of how hierarchical objects are represented in VWM.

People have the ability to attentively select and successfully track several moving objects, a process known as multiple-object tracking (MOT; Pylyshyn & Storm Spatial Vision 3: 179-197, 1988). Various factors have been known to influence MOT performance, such as speed, number of distractors, and proximity, while recent work has suggested that object trajectories may also be a factor (Fencsik, Kleiger, & Horowitz Perception and Psychophysics 69: 567-577, 2007). Meanwhile, unexpected changes in motion information have been demonstrated to be a critical facet for attracting attention Howard & Holcombe Attention, Perception & Psychophysics 72: 2087-2095, (2010). Therefore, we suggest that unexpected changes in target trajectories are an important factor in tracking performance. The research presented here controlled for spatial proximity while manipulating the number of instances in which an object changed trajectory. We found that spatial proximity had no effect on tracking performance but, rather, as the number of trajectory changes increased, tracking performance suffered. Results imply that the ability to track multiple moving objects is limited by unexpected changes in direction.

Objective: Our aim was to examine the specificity of the effects of acquiring expertise on visual working memory (VWM) and the degree to which higher levels of experience within the domain of expertise are associated with more efficient use of VWM. Background: Previous research is inconsistent on whether expertise effects are specific to the area of expertise or generalize to other tasks that also involve the same cognitive processes. It is also unclear whether more training and/or experience will lead to continued improvement on domain-relevant tasks or whether a plateau could be reached. Method: In Experiment 1, veterinary medicine students completed a one-shot visual change detection task. In Experiment 2, veterinarians completed a flicker change detection task. Both experiments involved stimuli specific to the domain of radiology and general stimuli. Results: In Experiment 1, veterinary medicine students who had completed an “eyes-on” radiological training demonstrated a domain-specific effect in which performance was better on the domain-specific stimuli than on the domain-general stimuli. In Experiment 2, veterinarians again showed a domain-specific effect, but performance was unrelated to the amount of experience veterinarians had accumulated. Conclusion: The effect of experience is domain specific and occurs during the first few years of training, after which a plateau is reached. Application: VWM training in one domain may not lead to improved performance on other VWM tasks. In acquiring expertise, eyes-on training is important initially, but continued experience may not be associated with further improvements in the efficiency of VWM.

Clutter can slow visual search. However, experts may develop attention strategies that alleviate the effects of clutter on search performance. In the current study we examined the effects of global and local clutter on visual search performance and attention strategies. Pilots and undergraduates searched for an elevation marker in charts of high, medium, and low global clutter. The target was in a low or high local clutter region of the chart or it was absent. High global and local clutter slowed search performance for both pilots and undergraduates. Pilots were more accurate but slower. Pilots’ search strategies differed from undergraduates in the following ways: they had more conservative criteria for responding target absent and spent more time processing the information within each fixation. Pilots and undergraduates used a coarse-to-fine search strategy in which, as the trial progressed, fixation durations increased and saccade distance decreased.

The present studies examined the roles of identity and spatial working memory in change detection. Observers completed a spatial or identity working m emory task concurrently with a change detection task. In the change detection task, participants we re presented naturalistic scenes that contained eit her a color or location change to one object. Concurren tly, participants remembered either the colors or locations of four squares. There was specific disru ption of performance when the working memory task and the change detection task loaded the same subsystem of working memory. There was also evidence that spatial information is processed more readily than identity information. This suggests that although there are separate systems for identi ty and spatial working memory, these subsystems are not necessarily created equal in that processing in the spatial processing may have priority over identity processing. However, this priority can be overridden during change detection if spatial memory is already occupied.

Objective: A novel model of measuring clutter in complex geospatial displays was compared with human ratings of subjective clutter as a measure of convergent validity. The new model is called the color-clustering clutter (C3) model. Background: Clutter is a known problem in displays of complex data and has been shown to affect target search performance. Previous clutter models are discussed and compared with the C3 model. Method: Two experiments were performed. In Experiment 1, participants performed subjective clutter ratings on six classes of information visualizations. Empirical results were used to set two free parameters in the model. In Experiment 2, participants performed subjective clutter ratings on aeronautical charts. Both experiments compared and correlated empirical data to model predictions. Results: The first experiment resulted in a .76 correlation between ratings and C3. The second experiment resulted in a .86 correlation, significantly better than results from a model developed by Rosenholtz et al. Outliers to our correlation suggest further improvements to C3. Conclusions: We suggest that (a) the C3 model is a good predictor of subjective impressions of clutter in geospatial displays, (b) geospatial clutter is a function of color density and saliency (primary C3 components), and (c) pattern analysis techniques could further improve C3. Application: The C3 model could be used to improve the design of electronic geospatial displays by suggesting when a display will be too cluttered for its intended audience.

In the experiment reported here, we examined the processes by which expected (probable) changes are detected more frequently than are unexpected (improbable) changes (the change probability effect; Beck, Angelone, & Levin, 2004). The change probability effect may be caused by a bias toward probable changes during encoding of the prechange aspect, during retrieval of the prechange aspect, or during activation of an explicit response to the change. Participants performed a change detection task for probable and improbable changes while their eye movements were tracked. Change detection performance was superior for probable changes, but long-term memory performance was equivalent for both probable and improbable changes. Therefore, although both probable and improbable prechange aspects were encoded, probable prechange aspects were more likely to be retrieved during change detection. Implicit change detection was also greater for probable changes than for improbable changes, suggesting that the change probability effect is the result of a bias during the retrieval and comparison stage of change detection. The stimuli used in the change detection task may be downloaded from www.psychonomic.org/archive.

Theories relating attention to change blindness (CB) imply that representations of objects in the focus of attention are stable and coherent. However, CB occurs for objects in the focus of attention. Here, we explore this apparent contradiction and the possibility that changes can be detected without having a complete and stable representation of the prechange object. The first experiment required observers to recognize a prechange object and a postchange object after viewing arrays of various sizes in which the prechange object was replaced by the postchange object after a brief delay. Results indicated that the representation of the prechange object was strong enough to cue a change but not strong enough to support accurate recognition. The remaining experiments demonstrated that the representation of the prechange object is volatile in that a shift in the display or the presence of a postchange object can disrupt the representation. These findings add to current theories of attention and representations by showing that attention may result in volatile representations that can support change detection without supporting accurate recognition.

Responses are quicker to predictable stimuli than if the time and place of appearance is uncertain. Studies that manipulate target predictability often involve overt cues to speed up response times. However, less is known about whether individuals will exhibit faster response times when target predictability is embedded within the inter-trial relationships. The current research examined the combined effects of spatial and temporal target predictability on reaction time (RT) and allocation of overt attention in a sustained attention task. Participants responded as quickly as possible to stimuli while their RT and eye movements were measured. Target temporal and spatial predictability were manipulated by altering the number of: 1) different time intervals between a response and the next target; and 2) possible spatial locations of the target. The effects of target predictability on target detection (Experiment 1) and target discrimination (Experiment 2) were tested. For both experiments, shorter RTs as target predictability increased across both space and time were found. In addition, the influences of spatial and temporal target predictability on RT and the overt allocation of attention were task dependent; suggesting that effective orienting of attention relies on both spatial and temporal predictability. These results indicate that stimulus predictability can be increased without overt cues and detected purely through inter-trial relationships over the course of repeated stimulus presentations.

In two experiments, adults who witnessed a videotaped event subsequently engaged in face-to-face interviews during which they were forced to confabulate information about the events they had seen. The interviewer selectively reinforced some of the participants' confabulated responses by providing confirmatory feedback (e.g., “Yes, _______is the correct answer”) and provided neutral (uninformative) feedback for the remaining confabulated responses (e.g., “O.K._______”). One week later, participants developed false memories for the events they had earlier confabulated knowingly. However, confirmatory feedback increased false memory for forcibly confabulated events, increased confidence in those false memories, and increased the likelihood that participants would freely report the confabulated events 1 to 2 months later. The results illustrate the powerful role of social-motivational factors in promoting the development of false memories.

In visual change detection tasks, providing a cue to the change location concurrent with the test image (post-cue) can improve performance, suggesting that, without a cue, not all encoded representations are automatically accessed. Our studies examined the possibility that post-cues can encourage the retrieval of representations stored in long-term memory (LTM). Participants detected changes in images composed of familiar objects. Performance was better when the cue directed attention to the post-change object. Supporting the role of LTM in the cue effect, the effect was similar regardless of whether the cue was presented during the inter-stimulus interval, concurrent with the onset of the test image, or after the onset of the test image. Furthermore, the post-cue effect and LTM performance were similarly influenced by encoding time. These findings demonstrate that monitoring the visual world for changes does not automatically engage LTM retrieval.

Although there has been some controversy as to whether attention is guided by memory during visual search, recent findings have suggested that memory helps to prevent attention from needlessly reinspecting examined items. Until now, it has been assumed that some form of retrospective memory is responsible for keeping track of examined items and preventing revisitations. Alternatively, some form of prospective memory, such as strategic scanpath planning, could be responsible for guiding attention away from examined items. We used a new technique that allowed us to selectively prevent retrospective or prospective memory from contributing to search. We demonstrated that both retrospective and prospective memory guide attention during visual search.

Expected Findings • More changes in trajectory will lead to lower tracking accuracy. • If changes in trajectory capture attention. o Probe detection will be better for probes on items that have just changed trajectory. § Indicating attentional attraction/capture. o Probe detection will be better when more changes in trajectory occur. § Suggesting frequent reallocations of attention. o Reaction times will be faster to probes on items that have recently changed trajectory. § Suggesting frequent reallocations of attention. 3.