This is like that: The use of earlier problems and the separation of similarity effects.

Novices attempting to solve a problem often are reminded of an earlier problem that illustrated a principle. Two experiments examined how these earlier problems are used and how this use is related to these remindings. Subjects studied four probability principles with related word problems. Test problems varied in their similarity to the study problems on story lines, objects, and correspondence of objects (variable roles). Experiment 1 tested whether remindings cue the principle or serve as the sources of detailed analogies. When the appropriate formula was provided with each test, the similarity of story lines had no effect, but object correspondences had a large effect. These results support an analogical account in which mapping is affected by the similarity of objects between study and test problems. Experiment 2 began to separate the aspects of similarity affecting the access and use of earlier problems by showing that, with confusable principles, similar story lines increased the access, but did not affect the use. The access appears to be sensitive to the relative similarity of examples because with distinctive principles, similar story lines had little effect. Discussion focuses on the further specification of the processes of noticing and analogical use of earlier problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of principle explanation and superficial similarity on analogical mapping in problem solving.

When solving a problem, people often make use of an earlier problem by mapping the objects from the earlier problem to the current one. Three experiments varied the superficial similarity between study and test problems to discriminate 2 views of the mapping process: direct mapping and near miss. Subjects studied 4 probability principles and study problems and solved test problems. The mapping of earlier problems on the basis of superficial similarity would lead to incorrect answers. In Experiment 1, evidence was found for the direct mapping view: Test problems with more similar objects to the study problems were more likely to be (inappropriately) mapped. However, in Experiment 2, in which the principle explanation was embedded in the study problem, this effect was reversed. In Experiment 3, 2 explanations for the differences in effect were contrasted. The discussion focuses on how principle explanation may affect analogical problem solving. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Object-based representations: Transfer between cases of continuous and discrete models of change.

The authors examined why similarities and differences between the objects of analogous problems affect transfer. They present results showing that object attributes affect transfer by affecting the way in which people represent problem structures (e.g., speed changes continuously and monetary investments discretely). Participants learned to solve problems involving either constant change in speed or in investment. They were then tested for transfer to problems that were matched on a variety of object attributes but involved entities known to be changing either continuously or discretely (e.g., melting ice vs. ice delivered to a restaurant). Although the manner of change was never specified as a constraint for solving the training problems, transfer in the continuous-to-discrete direction was rare and involved laborious mappings, whereas transfer in the discrete-to-continuous direction was frequent and straightforward. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Generalizing from the use of earlier examples in problem solving.

Novices often are reminded of earlier examples during problem solving. Four experiments examine the hypothesis that the use of earlier examples promotes generalizations about problem types, thereby influencing what is learned about the domain. Subjects studied four probability principles with word problems and then tried to solve two test problems for each principle. For half of the first tests, cues indicated which study problem might be used. All second tests were uncued. Experiments 1 and 2 showed that the first-test cuing led to an advantage on second-test performance for both the access and the use of relevant information. Experiments 3 and 4 demonstrated that this cuing benefit is due to some generalization induced from using the study problem to solve the first-test problem. Discussion focuses on the distinctions about how problem comparisons are used in learning and the implications of the view that remindings lead to generalizations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Practice schedules and subgoal instantiation in cascaded problem solving.

Fluent problem solving depends on efficient instantiation of subgoals for executing component skills. In 3 experiments, the authors examined how component-skill practice schedules and problem-solving demands interact to affect fluency in mental calculation. Participants practiced Boolean rules in blocked or random practice schedules and then solved problems that varied in the need to switch rules and in preview of upcoming operators. In Experiment 1, participants more quickly solved problems requiring repeated use of a single rule than problems using multiple rules, but practice schedules had no effect. In Experiment 2, random practice produced a transfer benefit for multiple-rule problems that allowed operator preview. Experiment 3 verified the importance of preview. These results suggest that when participants can rapidly switch rules, they achieve fluency by overlapping steps in a manner analogous to perceptual-motor skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social categorization and perceptual judgment of size: When perception is social.

Social knowledge may affect not only people's thoughts and judgments but also their actual perceptions of physical magnitude. The physical magnitude of a stimulus is perceived in a relative way, comparing the magnitude of the target surrounding context stimuli. Because similar objects invite comparison processes more easily than dissimilar objects ("similarity breeds comparability"), social knowledge can affect judgments of physical magnitude by determining what is perceived as (dis) similar. In Experiment 1, the authors show that social categorizations that are based on physical cues (e. g., gender) may affect the magnitude of perceptual contrast effects (the Ebbinghaus illusion). More important, in Experiment 2, the influence of social categorizations that have no physical bases is shown to affect the magnitude of perceptual contrast effects. Implications of these findings for theories of social knowledge effects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the relations between seen objects and components of potential actions.

Accounts of visually directed actions usually assume that their planning begins with an intention to act. This article describes three experiments that challenged this view through the use of a stimulus-response compatibility paradigm with photographs of common graspable objects as stimuli. Participants had to decide as fast as possible whether each object was upright or inverted. Experiments 1 and 2 examined the effect of the irrelevant dimension of left-right object orientation on bimanual and unimanual keypress responses. Experiment 3 examined wrist rotation responses to objects requiring either clockwise or anticlockwise wrist rotations when grasped. The results (a) are consistent with the view that seen objects automatically potentiate components of the actions they afford, (b) show that compatibility effects of an irrelevant stimulus dimension can be obtained across a wide variety of naturally occurring stimuli, and (c) support the view that intentions to act operate on already existing motor representations of the possible actions in a visual scene. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of a diagram retrieval cue on spontaneous analogical transfer.

Investigated the effect of a retrieval manipulation on spontaneous transfer in problem solving in 81 undergraduates. Ss read a story illustrating a problem and its solution prior to solving an analogous transfer problem in a different semantic domain. The story contained diagrams that schematically depicted the problem and solution presented in the story. A visual retrieval cue for the prior story was manipulated by including one of the story's diagrams with the transfer problem. Results indicate that the retrieval cue facilitated spontaneous transfer although additional Ss showed transfer when a hint was given by the experimenter to use the prior story to solve the problem. Similar results of spontaneous transfer and transfer obtained with a hint were obtained for Ss who received only diagrams prior to solving the transfer problem. The educational implications of retrieval manipulations in problem solving are discussed. (French abstract) (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Homonymy in the lexicons of young children acquiring American Sign Language

The effect of stimulus factors such as interobject similarity and stimulus density on the recognition of objects across changes in view was investigated in five experiments. The recognition of objects across views was found to depend on the degree of interobject similarity and on stimulus density: recognition was view dependent when both interobject similarity and stimulus density were high, irrespective of the familiarity of the target object. However, when stimulus density or interobject similarity was low recognition was invariant to viewpoint. It was found that recognition was accomplished through view-dependent procedures when discriminability between objects was low. The findings are discussed in terms of an exemplar-based model in which the dimensions used for discriminating between objects are optimised to maximise the differences between the objects. This optimisation process is characterised as a perceptual 'ruler' which measures interobject similarity by stretching across objects in representational space. It is proposed that the 'ruler' optimises the feature differences between objects in such a way that recognition is view invariant but that such a process incurs a cost in discriminating between small feature differences, which results in view-dependent recognition performance.     

Why the visual recognition system might encode the effects of illumination

A key problem in recognition is that the image of an object depends on the lighting conditions. We investigated whether recognition is sensitive to illumination using 3-D objects that were lit from either the left or right, varying both the shading and the cast shadows. In experiments 1 and 2 participants judged whether two sequentially presented objects were the same regardless of illumination. Experiment 1 used six objects that were easily discriminated and that were rendered with cast shadows. While no cost was found in sensitivity, there was a response time cost over a change in lighting direction. Experiment 2 included six additional objects that were similar to the original six objects making recognition more difficult. The objects were rendered with cast shadows, no shadows, and as a control, white shadows. With normal shadows a change in lighting direction produced costs in both sensitivity and response times. With white shadows there was a much larger cost in sensitivity and a comparable cost in response times. Without cast shadows there was no cost in either measure, but the overall performance was poorer. Experiment 3 used a naming task in which names were assigned to six objects rendered with cast shadows. Participants practised identifying the objects in two viewpoints lit from a single lighting direction. Viewpoint and illumination invariance were then tested over new viewpoints and illuminations. Costs in both sensitivity and response time were found for naming the familiar objects in unfamiliar lighting directions regardless of whether the viewpoint was familiar or unfamiliar. Together these results suggest that illumination effects such as shadow edges: (1) affect visual memory; (2) serve the function of making unambigous the three-dimensional shape; and (3) are modeled with respect to object shape, rather than simply encoded in terms of their effects in the image.     

Having the Memory of an Elephant: Long-Term Retrieval and the Use of Analogues in Problem Solving.

The authors report 4 experiments exploring long-term analogical transfer from problem solutions in folk tales participants heard during childhood, many years before encountering the target problems. Substantial culture-specific analogical transfer was found when American and Chinese participants' performance was compared on isomorphs of problems solved in European versus Chinese folk tales. There was evidence of transfer even among participants who did not report being reminded of the source tale while solving the target problem. Comparisons of different versions of a target problem indicated that similarity of solution tool affected accessing, mapping, and executing components of problem solving, whereas similarity of goal object had only a moderate effect on accessing. High school students also evidenced greater transfer than did middle school students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An interactive activation approach to object processing: effects of structural similarity, name frequency, and task in normality and pathology

We present a computational model of the processes involved in retrieving stored semantic and name information from objects, using a simple interactive activation and competition architecture. We simulate evidence showing a cross-over in normal reaction times to make semantic classification and identification responses to objects from categories with either structurally similar or structurally dissimilar exemplars, and that identification times to objects from these two different classes correlate differentially with measures of the structural similarity of objects within the category and the frequency of the object's name. Structural similarity exerts a negative effect on object decision as well as naming, though this effect is larger on naming. Also, on naming, structural similarity interacts with the effects of name frequency, captured in the model by varying the weight on connections from semantic to name units; frequency effects are larger with structurally dissimilar items. In addition, (1) the range of potential errors for objects from these two classes, when responses are elicited before activation reached a stable state, differ--a wider range of errors occur to objects from categories with structurally similar exemplars; and (2) simulated lesions to different locations within the model produce selective impairments to identification but not to semantic classification responses to objects from categories with structurally similar exemplars. We discuss the results in relation to data on visual object processing in both normality and pathology.     

The human pulvinar and stimulus-driven attentional control.

The present study compared the behavioral effects of sudden motion onsets or color changes (i.e., featural changes) with the effects of new objects (i.e., multiple changes). Experiments 1 and 2 showed that lesions of the pulvinar affect stimulus-driven attentional control only when it is triggered by featural changes, but not by new objects. Experiment 3 revealed that when appended on a new object, a featural change is processed as a part of a more massive new object: Its attentional effects are larger and remain undisturbed by lesions of the pulvinar. In Experiment 4 a temporal superiority effect was found for featural changes, but not for new objects in healthy subjects. These results suggest that featural changes and new objects may be processed through different pathways and that the pulvinar may be particularly involved in stimulus-driven attentional control by sudden events entailing featural changes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A model of perceptual classification in children and adults.

The developmental trend from overall-similarity to dimensional-identity classifications is explained by a quantitative model. I begin with the assumption that objects are represented in terms of constituents dimensions and that the representation of objects changes little with development. Given this assumption, the model has three major parts. First, the similarity between objects is a function of the combination of the constituent dimensional differences. I propose developmental change in likelihood that dimensions are differentially weighted in the calculation of similarity. Second, the perceived similarities between objects are valued for the purpose of constructing classifications. I propose that similarities are valued more dichotomously with age, such that identity becomes increasingly special. Third, the valued similarities are used to choose the best classification of those possible. The model provides good qualitative fits to the extant data. Three experiments examining classifications in 2- to 8-year-olds and in adults support specific new claims of the model. The data and the model provide new insights about development, classification, and similarity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of background information on object identification.

Previous research using briefly presented displays has indicated that objects in a coherent scene are easier to identify than are objects in incoherent backgrounds. Of interest is whether the identification of the target object depends on the identification of the scene or the identification of other diagnostic objects in the scene. Experiment 1 indicated objects are more difficult to identify when located in an "episodically" inconsistent background even when the same diagnostic objects are present in both inconsistent and consistent backgrounds. Experiment 2 demonstrated that the degree to which noncued (cohort) objects are consistent with the target object has no effect on this object identification task. Experiment 3 showed consistent episodic background information facilitated object identification and inconsistent episodic background information did not interfere relative to "nonsense" backgrounds roughly equated on visual characteristics. Implications for models of scene perception are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ease of processing constrains the activation flow in the conceptual-lexical system during speech planning.

In 3 picture–word interference experiments, speakers named a target object in the presence of an unrelated not-to-be-named context object. Distractor words, which were phonologically related or unrelated to the context object's name, were used to determine whether the context object had become phonologically activated. All objects had high frequency names, and the ease of processing of these objects was manipulated by a visual degradation technique. In Experiment 1, both objects were nondegraded; in Experiment 2, both objects were degraded; and in Experiment 3, either the target object or the context object was degraded. Distractor words, which were phonologically related to the context objects, interfered with the naming response when both objects were nondegraded, indicating that the context objects had become phonologically coactivated. The effect vanished when both objects were degraded, when only the context object was degraded, and when only the target object was degraded. These data demonstrate that the amount of available processing resources constrains the forward cascading of activation in the conceptual-lexical system. Context objects are likely to become phonologically coactivated if they are easily retrieved and if prioritized target processing leaves sufficient resources. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The effect of line configuration on perceived numerosity of dotted lines

Estimates the number of objects in a line are made in many different situations. This paper demonstrates that besides the actual number of dots, aspects of line configuration affect the perceived numerosity of dotted lines. Experiment 1 provides evidence that the highly studied "clutter effect" in distance perception research replicates to the numerosity domain so that lines made up of more segments are perceived to contain more dots. Experiments 2-5 provide nomological validity for the recently proposed "direct distance" effect in distance perceptions by showing that numerosity perceptions are higher the greater the euclidean length between the line end points and by manipulating euclidean length in three orthogonal ways: the relative length of segments (Experiment 2), the angle between segments (Experiment 3), and the general direction of segments (Experiment 4). Experiment 5 conceptually replicates the results of Experiments 2-4 utilizing stimuli-based versus memory-based judgments and a discrimination task. Experiments 6 and 7 extend the research on spatial perception by demonstrating that the use of euclidean length as a source of information is inversely related to line width, with width varied through clutter (Experiment 6) and total line length (Experiment 7). Overall, the results demonstrate that the robustness of the euclidean length effect is contingent on the salience of alternative spatial heuristics--specifically, euclidean width. Theoretical implications are discussed.     

Finding the Critical Facts: Children's Visual Scan Patterns When Solving Story Problems That Contain Irrelevant Information.

Two experiments were conducted to understand the processes through which 5th graders discriminate relevant from irrelevant information when solving mathematical story problems. Visual scanning was recorded and coded as directed toward relevant information, irrelevant information, the question, workspace, and elsewhere. Experiment 1 focused on the effects of irrelevant numerical information, and Experiment 2 focused on irrelevant qualitative information. The visual scanning results showed that higher achieving and lower achieving students generally used question-guided comparisons of the relevant and irrelevant information when they succeeded. A 2nd effective strategy was to discriminate during their initial reading of the problems. In addition, whereas higher achieving students flexibly varied their visual scanning to fit with problem difficulty, the lower achievers showed less flexibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)