Relational Integration and Executive Function in Alzheimer's Disease.

Executive functions depend on the ability to represent relations between objects and events, and the prefrontal cortex provides the neural substrate for this capacity. Patients with probable Alzheimer's disease (AD) and control participants were administered measures of working memory and reasoning that varied systematically in their relational complexity. AD patients showed impairment on reasoning measures that required the online integration of relations but performed as well as control participants on nonrelational items and items requiring the processing of only single relations. When AD patients were divided into subgroups based on their performance on relational reasoning measures, the subgroup that showed significant impairment on relational integration measures exhibited a neuropsychological profile consistent with prefrontal cortical dysfunction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relational Integration, Inhibition, and Analogical Reasoning in Older Adults.

The difficulty of reasoning tasks depends on their relational complexity, which increases with the number of relations that must be considered simultaneously to make an inference, and on the number of irrelevant items that must be inhibited. The authors examined the ability of younger and older adults to integrate multiple relations and inhibit irrelevant stimuli. Young adults performed well at all but the highest level of relational complexity, whereas older adults performed poorly even at a medium level of relational complexity, especially when irrelevant information was presented. Simulations based on a neurocomputational model of analogical reasoning, Learning and Inference with Schemas and Analogies (LISA), suggest that the observed decline in reasoning performance may be explained by a decline in attention and inhibitory functions in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

If Saddam is Hitler then who is George Bush? Analogical mapping between systems of social roles.

The analogy between World War II and the 1991 Persian Gulf crisis led people to construct a coherent system of roles for the participants in the Gulf crisis. The Analogical Constraint Mapping Engine (ACME), a model of analogical mapping by constraint satisfaction (K. J. Holyoak & P. Thagard, 1989), makes predictions about the types of correspondences people are likely to draw between the people and countries in these analogs. Both a survey (Exp 1) and an experimental study (Exp 2) revealed clear evidence that people have a strong tendency to generate mappings that honor certain basic coherence constraints. In Exp 3, with science-fiction materials, further evidence for the generality of these constraints was obtained. Computer simulations of Exps 2 and 3 using ACME yielded mappings similar to those generated by Ss. General models of analogical reasoning may have implications for everyday understanding of complex systems of social roles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social reference points.

Conducted 2 experiments in which a total of 324 undergraduates were asked to make similarity judgments about social concepts, varying the direction of the comparison specified by the question. Asymmetries in rated similarity were used to diagnose concepts that function as habitual reference points. In Exp I, after completing the Self-Monitoring Scale, Ss were asked to make directional judgments about themselves vs a friend along various dimensions (social and physical). Ss were found to rate a friend as more similar to themselves than vice versa along both social and physical dimensions, suggesting that the self served as a reference point. In Exp II Ss made global similarity comparisons between themselves and typical examples of various social stereotypes. Directional asymmetries were inversely related to the extent of Ss' knowledge about the stereotypes: The self acted as a reference point with respect to stereotypes with few known attributes but not with respect to those with many attributes. The relation between level of self-monitoring and asymmetry effects was weak and inconsistent in both experiments. Results suggest that concepts serving as social reference points vary across judgment contexts in accord with general cognitive models of similarity comparisons. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reasoning and learning by analogy: Introduction.

Analogy is a powerful cognitive mechanism that people use to make inferences and learn new abstractions. The history of work on analogy in modern cognitive science is sketched, focusing on contributions from cognitive psychology, artificial intelligence, and philosophy of science. This review sets the stage for the 3 articles that follow in this Science Watch section. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A symbolic-connectionist theory of relational inference and generalization.

The authors present a theory of how relational inference and generalization can be accomplished within a cognitive architecture that is psychologically and neurally realistic. Their proposal is a form of symbolic connectionism: a connectionist system based on distributed representations of concept meanings, using temporal synchrony to bind fillers and roles into relational structures. The authors present a specific instantiation of their theory in the form of a computer simulation model, Learning and Inference with Schemas and Analogies (LISA). By using a kind of self-supervised learning, LISA can make specific inferences and form new relational generalizations and can hence acquire new schemas by induction from examples. The authors demonstrate the sufficiency of the model by using it to simulate a body of empirical phenomena concerning analogical inference and relational generalization. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Mapping conceptual to spatial relations in visual reasoning.

In 3 experiments, the authors investigated the impact of goals and perceptual relations on graph interpretation when people evaluate functional dependencies between continuous variables. Participants made inferences about the relative rate of 2 continuous linear variables (altitude and temperature). The authors varied the assignments of variables to axes, the perceived cause–effect relation between the variables, and the causal status of the variable being queried. The most striking finding was that accuracy was greater when the slope-mapping constraint was honored, which requires that the variable being queried be assigned to the vertical axis, so that steeper lines map to faster changes in the queried variable. The authors propose that graphs provide external instantiations of intermediate mental representations, enabling people to move from visuospatial representations to abstractions through the use of natural mappings between perceptual and conceptual relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A theory of conditioning: Inductive learning within rule-based default hierarchies.

We present a theory of classical conditioning based on a parallel, rule-based performance system integrated with mechanisms for inductive learning. Inferential heuristics are used to add new rules to the system in response to the relation between the system's predictions and environmental input. A major heuristic is based on "unusualness": Novel cues are favored as candidates to predict events that are important or unexpected. Rules have strength values that are revised on the basis of feedback. The performance system allows rules to operate in parallel, competing to control behavior and obtain reward for successful prediction of important events. Sets of rules can form default hierarchies: Exception rules censor useful but imperfect default rules, protecting them from loss of strength. The theory is implemented as a computer simulation, which is used to model a broad range of conditioning phenomena, including blocking and overshadowing, the impact of statistical predictability on conditioning, and conditioned inhibition. The theory accounts for a variety of phenomena that previous theories have not dealt with successfully. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Verb imagery and noun phrase concreteness in the recognition and recall of sentences.

Examined the role of verb imagery and noun phrase concreteness in determining sentence imagery and memory in 2 experiments with a total of 111 male and 17 female university students. Semantic changes in sentences were recognized more often if the noun phrases were concrete rather than abstract. Free recall of sentences was affected similarly by phrase concreteness. Verb imagery, however, had no effect on either recognition or recall performance. Analysis of recall by type of word indicated that organization of recall centered upon the nouns. Implications of these results for the hypothesis of imaginal coding of concrete sentence meaning are discussed. (French summary) (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of gamma-band synchronization in priming of form discrimination for multiobject displays.

Previous research has shown that synchronized flicker can facilitate detection of a single Kanizsa square. The present study investigated the role of temporally structured priming in discrimination tasks involving perceptual relations between multiple Kanizsa-type figures. Results indicate that visual information presented as temporally structured flicker in the gamma band can modulate the perception of multiple objects in a subsequent display. For judgments of both relative orientation and relative position of 2 rectangles, response time to identify and discriminate relations between the objects was consistently decreased when the vertices corresponding to distinct Kanizsa-type rectangles were primed asynchronously. Implications are discussed for models of the perception of objects and their interrelations. (PsycINFO Database Record (c) 2011 APA, all rights reserved)