Color versus shape coding in information displays.

8 Ss counted objects of a specified color or shape on displays of 20, 60, or 100 items. Counting time and errors increased with increasing display density. Counting based on a 5-valued color code was faster and more accurate than counting using any of 3 shape codes. Color counting was not affected by the particular shape code on which the colors were superimposed. Shape counting was somewhat faster and/or more accurate when color did not vary on the display, and vice versa. Differences in counting performance appeared among the 3 shape codes and among certain of the symbols within shape codes, and small differences were confirmed among the particular code colors used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual search asymmetries within color-coded and intensity-coded displays.

Color and intensity coding provide perceptual cues to segregate categories of objects within a visual display, allowing operators to search more efficiently for needed information. Even within a perceptually distinct subset of display elements, however, it may often be useful to prioritize items representing urgent or task-critical information. The design of symbology to produce search asymmetries (Treisman & Souther, 1985) offers a potential technique for doing this, but it is not obvious from existing models of search that an asymmetry observed in the absence of extraneous visual stimuli will persist within a complex color- or intensity-coded display. To address this issue, in the current study we measured the strength of a visual search asymmetry within displays containing color- or intensity-coded extraneous items. The asymmetry persisted strongly in the presence of extraneous items that were drawn in a different color (Experiment 1) or a lower contrast (Experiment 2) than the search-relevant items, with the targets favored by the search asymmetry producing highly efficient search. The asymmetry was attenuated but not eliminated when extraneous items were drawn in a higher contrast than search-relevant items (Experiment 3). Results imply that the coding of symbology to exploit visual search asymmetries can facilitate visual search for high-priority items even within color- or intensity-coded displays. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Partitioning and saturation of visual displays and efficiency of visual search.

The time required to locate a constant number of signals (ten diamonds) in a square display when (a) the number of irrelevant signals (squares and circles) was varied from 10 to 70 and (b) the number of partitions in the display was varied by use of grid lines to produce a 9 X 9, 13 X 13, or 16 X 16 matrix was determined. Search time increased both when the number of irrelevant signals was increased and when the number of partitions was increased. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related differences in visual search in dynamic displays.

The authors examined the ability of younger and older adults to detect changes in dynamic displays. Older and younger adults viewed displays containing numerous moving objects and were asked to respond when a new object was added to the display. Accuracy, response times, and eye movements were recorded. For both younger and older participants, the number of eye movements accounted for a large proportion of variance in transient detection performance. Participants who actively searched for the change performed significantly worse than did participants who employed a passive or covert scan strategy, indicating that passive scanning may be a beneficial strategy in certain dynamic environments. The cost of an active scan strategy was especially high for older participants in terms of both accuracy and response times. However, older adults who employed a passive or covert scan strategy showed greater improvement, relative to older active searchers, than did younger adults. These results highlight the importance of individual differences in scanning strategy in real-world dynamic, cluttered environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Training older adults to search more effectively: Scanning strategy and visual search in dynamic displays.

The authors examined the ability of older adults to modify their search strategies to detect changes in dynamic displays. Older adults who made few eye movements during search (i.e., covert searchers) were faster and more accurate compared with individuals who made many eye movements (i.e., overt searchers). When overt searchers were instructed to adopt a covert search strategy, target detection performance increased to the level of natural covert searchers. Similarly, covert searchers instructed to search overtly exhibited a decrease in target detection performance. These data suggest that with instructions and minimal practice, older adults can ameliorate the cost of a poor search strategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The interaction of information displays with control system dynamics in continuous tracking.

9 Ss were each seated in a mockup of a fighter-type cockpit where they each moved a control stick to cause movement of a line on the TV-like picture tube… . "in no condition of this experiment was the following display found to be superior to the compensatory display… . Examination of significant subject interactions with treatments showed deviation in individual cases from the averaged group data." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Information assimilation from updated alphanumeric displays.

The accuracy with which Ss could locate updated elements of information was studied as a function of use of coded vs. uncoded updates, number of elements of information presented, and number of elements of information updated. Selected findings demonstrate the value of coding as an information enhancement technique and the considerable effects of elements presented and updated. With uncoded displays a reduction in the percentage of responses as the number of updates increased may reflect a lessening of Ss' confidence in their ability to make correct responses even though their actual performance did not appear to suffer. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of two visual display presentations.

The applicability of the results of dial legibility studies based on slide presentations to legibility of actual dials was tested experimentally by comparison of time and error measures for reading actual dials, and reading slide projections of the dials. There was a slight but insignificant advantage in favor of panelmounted slides over projection of pictures of the slides. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of display, response, and response set factors upon the storage of spatial information in complex displays.

Immediate recall for spatial information was studied as a function of stimulus load under 2 display formats, 2 response formats, and 2 response set conditions. 4 groups of 10 Ss each served under 15 replications of all response-format, stimulus-load conditions; groups were distinguished on the basis of display format and set. Each S viewed either a spatial or tabular display of 14-26 geometrical stimuli for 16 sec.; he was then required to report, on either a tabular or spatial response form, the location of relevant stimuli. Correct responses and misplacement errors increased more rapidly for the spatial format as more stimuli were presented. Recoding from 1 display to the other response format did not yield serious decrements. Contrary to expectation, response set enhanced all conditions to a nearly equivalent degree. Results are interpreted in terms of the "chunking" hypothesis. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Decision quality as a measure of visual display effectiveness.

A new gaming technique was employed in an attempt to evaluate more accurately the effectiveness of visual displays. 18 male university students acted as traffic managers for a hypothetical trucking concern. Trucking information was presented in map-plus-overlay displays, and Ss manipulated trucks, drivers, and loads within the framework of the economic rules governing the trucking operation. A computer program was written which determined the profit in dollars of each S's performance. 3 independent variables—use of color, fact density, and compression (ratio of symbols to facts)—were used in this repeated measures design. Analysis of variance indicated that profit was a positive function of increasing fact density (p     

More than just finding color: Strategy in global visual search is shaped by learned target probabilities.

In 2 experiments, eye movements were examined during searches in which elements were grouped into four 9-item clusters. The target (a red or blue T) was known in advance, and each cluster contained different numbers of target-color elements. Rather than color composition of a cluster invariantly guiding the order of search though clusters, the use of color was determined by the probability that the target would appear in a cluster of a certain color type: When the target was equally likely to be in any cluster containing the target color, fixations were directed to those clusters approximately equally, but when targets were more likely to appear in clusters with more target-color items, those clusters were likely to be fixated sooner. (The target probabilities guided search without explicit instruction.) Once fixated, the time spent within a cluster depended on the number of target-color elements, consistent with a search of only those elements. Thus, between-cluster search was influenced by global target probabilities signaled by amount of color or color ratios, whereas within-cluster search was directly driven by presence of the target color. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual information and attentional constraints in visual search of collision events.

This study examined the detection of collision events when multiple moving objects were present in the scene. Observers were presented with displays simulating a 3-D environment with multiple moving objects. The authors examined the ability of observers to detect collisions using a signal-detection paradigm and a visual search paradigm. The results indicated that, overall, observers were quite accurate at detecting collisions. Observers used both expansion information and static position to detect collisions, with expansion information being the more important source. Singleton search conditions were not processed in parallel, and conjunction search conditions had poorer performance than singleton search conditions. In addition, reaction times were greater for target-present trials as compared with target-absent trials. The results are interpreted in terms of 4 visual search hypotheses for collision detection when multiple moving objects are present. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Flicker is a primitive visual attribute in visual search.

At the earliest processing stages, visual stimuli are decomposed by a set of filters tuned to specific values of such attributes as colour, orientation, and motion. These filters have been characterised both neurophysiologically and behaviourally. The single exception is the attribute of flicker that has been characterised neurophysiologically but not behaviourally. Using a visual search paradigm, the authors provide the first behavioural demonstration that flicker is indeed a primitive attribute used by the visual system in stimulus encoding. Consistent with the temporal contrast-sensitivity function, sensitivity to flicker was highest at about 10 Hz and decreased as the flicker rate was either increased or decreased. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Two-year-olds' search strategies and visual tracking in a hidden displacement task.

Children younger than 3 years have difficulty with search tasks that involve hidden displacement. Partial visual information was provided about a ball's path as it moved toward a hiding place. Children (2.0 and 2.5 years old) saw a ball rolling down a ramp placed behind a transparent screen with 4 opaque doors. A wall, placed on the ramp and directly behind 1 of the doors, protruded above the screen and stopped the ball. Children were asked to find the ball. The transparency of the screen permitted visual tracking of the ball between the doors, but its final resting place was obscured. Both age groups were equally proficient at tracking the ball as it rolled behind the screen, but the 2.5-year-olds were more likely to reach to the correct door. Looking behavior was related to errors in the younger group in that tracking that stopped short or continued past the correct door was associated with incorrect choices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of structure and component in judgments of visual similarity of Chinese characters.

Skilled readers of Chinese participated in sorting and visual search experiments. The sorting results showed that under conditions of conflicting information about structure and component, subjective judgments of the visual similarity among characters were based on the characters' overall configurations (i.e., structures) rather than on the common components the characters possessed. In visual search, both structure and component contributed to the visual similarity reflected by the search efficiency. The steepest search slopes (thus the most similar target-distractor pairs) were found when the target and the distractor characters had the same structure and shared 1 common component, compared with when they had different structures and/or shared no common components. Results demonstrated that character structure plays a greater role in the visual similarity of Chinese characters than has been considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of within-dimension singleton priming in visual search.

The authors report a newly identified intertrial priming phenomenon, within-dimension singleton priming, by which search for a target that happens to be a singleton on the current trial is faster when the target on the previous trial had also been a singleton on the same dimension rather than a nonsingleton. This effect was replicated in 6 experiments with different procedures, with singletons on various dimensions, when the featural contrast defining the singleton remained the same or changed within a dimension from one trial to the next, and when the target was a singleton on a target-defining dimension or on an irrelevant dimension. These findings cannot be explained by previously demonstrated intertrial repetition effects such as dimension-specific priming or priming of popout. Theoretical implications of the within-dimension singleton priming phenomenon are discussed relative to the dimension-weighting hypothesis, the role of stimulus-driven salience in feature-guided search, and the roles of intertrial priming and goal-directed factors in visual search. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Superior visual search in autism.

Children with a diagnosis of autism and normally developing children, matched for age and general ability, were tested on a series of visual search tasks in 2 separate experiments. The children with autism performed better than the normally developing children on difficult visual search tasks,. This result occurred regardless of whether the target was uniquely defined by a single feature or a conjunction of features, as long as ceiling effects did not mask the difference. Superior visual search performance in autism can be seen as analogous to other reports of enhanced unique item detection in autism. Unique item detection in autism is discussed in the light of mechanisms proposed to be involved in normal visual search performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Featural guidance in conjunction search: The contrast between orientation and color.

Four experiments examined the effects of precues on visual search for targets defined by a color-orientation conjunction. Experiment 1 showed that cueing the identity of targets enhanced the efficiency of search. Cueing effects were stronger with color than with orientation cues, but this advantage was additive across array size. Experiment 2 demonstrated that cueing effects interacted with bottom-up segmentation processes, whereas Experiment 3 showed the stronger effects of color cues remained in a compound task. Experiment 4 confirmed the enhanced effect of color cueing even when verbal rather than visual cues were used. The targets used were balanced for search efficiency within both orientation and color dimensions. We suggest search benefits from the top-down cueing of color compared with orientation because color cueing enhances the segmentation of displays into color groups more efficiently. This enables search to an appropriate color group to be initiated earlier. We discuss how top-down segmentation processes interact with differences in bottom-up segmentation to further improve target detection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Integrality/separability of stimulus dimensions and multidimensional generalization in pigeons.

The authors present a quantitative framework for interpreting the results of multidimensional stimulus generalization experiments in animals using concepts derived from the geometrical approach to human cognition. The authors apply the model to the analysis of stimulus generalization data obtained from pigeons trained with different sets of stimuli varying along two orthogonal dimensions. Separable pigeons were trained with stimuli varying along the dimensions of circle size and line tilt, dimensions found to be separable in previous human research; integral pigeons were trained with stimuli varying along two dimensions of rotation in depth, dimensions that are intuitively integral and which hold special interest for theories of object recognition. The model accurately described the stimulus generalization data, with best fits to the City-Block metric for separable pigeons and to the euclidean metric for integral pigeons. (PsycINFO Database Record (c) 2010 APA, all rights reserved)