Rostrolateral prefrontal cortex involvement in relational integration during reasoning.

Patient and neuroimaging studies indicate that complex reasoning tasks are associated with the prefrontal cortex (PFC). In this study, we tested the hypothesis that the process of relational integration, or considering multiple relations simultaneously, is a component process of complex reasoning that selectively recruits PFC. We used fMRI to examine brain activation during 0-relational, 1-relational, and 2-relational problems adapted from the Raven's Progressive Matrices and hypothesized that PFC would be preferentially recruited by the 2-relational problem type. Event-related responses were modeled by convolving a canonical hemodynamic response function with the response time (RT) associated with each trial. The results across different analyses revealed the same pattern: PFC activation was specific to the comparison between 2- and 1-relational problems and was not observed in the comparison between 1- and 0-relational problems. Furthermore, the process of relational integration was specifically associated with bilateral rostrolateral PFC (RLPFC; lateral area 10) and right dorsolateral PFC (areas 9 and 46). Left RLPFC showed the greatest specificity by remaining preferentially recruited during 2-relational problems even after comparisons were restricted to trials matched for RT and accuracy. The link between RLPFC and the process of relational integration may be due to the associated process of manipulating self-generated information, a process that may characterize RLPFC function.

The emergence of coherence over the course of decision making.

Previous research has indicated that decision making is accompanied by an increase in the coherence of assessments of the factors related to the decision alternatives. In the present study, the authors investigated whether this coherence shift is obtained before people commit to a decision, and whether it is obtained in the course of a number of other processing tasks. College students were presented with a complex legal case involving multiple conflicting arguments. Participants rated agreement with the individual arguments in isolation before seeing the case and after processing it under various initial sets, including playing the role of a judge assigned to decide the case. Coherence shifts were observed when participants were instructed to delay making the decision (Experiment 1), to memorize the case (Experiment 2), and to comprehend the case (Experiment 3). The findings support the hypothesis that a coherence-generating mechanism operates in a variety of processing tasks, including decision making.

Analogical priming via semantic relations.

Research on semantic memory has often tacitly treated semantic relations as simple conduits for spreading activation between associated object concepts, rather than as integral components of semantic organization. Yet conceptual relations, and the role bindings they impose on the objects they relate, are central to such cognitive tasks as discourse comprehension, inference, problem solving, and analogical reasoning. The present study addresses the question of whether semantic relations and their bindings can influence access to semantic memory. The experiments investigated whether, and under what conditions, presenting a prime pair of words linked by 1 of 10 common semantic relations would facilitate processing of a target pair of words linked by the same relation. No effect was observed when participants merely read the prime; however, relational priming was observed under instructions to note and use the semantic relations. Participants were faster at making a lexical decision or naming a word on a related pair of target words when that pair was primed with an analogously related pair of words than when the prime pair consisted of either two unrelated words or two words linked by some other relation. This evidence of analogical priming suggests that under an appropriate strategic set, lexical decisions and naming latencies can be influenced by a process akin to analogical mapping.

The use of diagrams in analogical problem solving.

In four experiments, we examined the impact of perceptual properties on the effectiveness of diagrams in analogical problem solving, using variants of convergence diagrams as source analogues for the radiation problem. Static diagrams representing the initial problematic state (one large line directed at a target) and the final state for a convergence solution (multiple converging lines) were not accessed spontaneously but were often used successfully once a hint to consider the diagram had been provided. The inaccessibility of static diagrams was not alleviated by adding additional diagrams to represent intermediate states (Experiment 1), but spontaneous access was improved by augmenting static diagrams with a verbal statement of the convergence principle (Experiment 3). Spontaneous retrieval and noticing were increased markedly by animating displays representing converging forces and thereby encouraging encoding of the lines as indicating motion toward a target (Experiments 3 and 4). However, neither static nor animated diagrams were effective when the arrows were reversed to imply divergence rather than convergence (Experiment 2). The results indicate that when animation encourages the interpretation of a diagram as a helpful source analogue, it can greatly enhance analogical transfer.

The role of working memory in analogical mapping.

The impact of a working-memory load on analogical mapping was examined in two experiments, using a dual-task paradigm. In Experiment 1, we used a phonological working-memory load; in Experiment 2, we used a phonological working-memory load and an executive working-memory load. The subjects were required to identify correspondences between visual scenes, either for single objects or for three objects simultaneously. The results indicated that the imposition of either a phonological or an executive working-memory load decreased the frequency with which the subjects identified correspondences between scenes based on relations and increased the frequency with which they identified correspondences based on object attributes. The frequency with which subjects made relational mappings was increased by the instruction to find correspondences for multiple objects in a scene simultaneously, rather than for just one. These results indicate that mapping on the basis of relations places greater demands on both modality-specific buffers and executive components of working memory than does mapping on the basis of object attributes.

Determining whether causal order affects cue selection in human contingency learning: comments on Shanks and Lopez (1996)

Shanks and Lopez (1996) reported three experiments in which they attempted to test whether causal order affects cue selection, and concluded that it does not. Their study provides an opportunity to highlight some basic methodological criteria that must be met in order to test whether and how causal order influences learning. In particular, it is necessary to (1) ensure that participants consistently interpret the learning situation in terms of directed cause-effect relations; (2) measure the causal knowledge they acquire; (3) manipulate causal order; and (4) control the statistical relations between cause and effect. With respect to these criteria, each experiment reported by Shanks and Lopez fails on multiple counts. Moreover, several aspects of the results reported by Shanks and Lopez are explained by causal-model theory, but not by associative accounts. Their study thus adds to a growing body of evidence from different laboratories indicating that human contingency learning can be guided by causal interpretation.

Reasoning and learning by analogy.

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.

The analogical mind.

The use of analogy in human thinking is examined from the perspective of a multiconstraint theory, which postulates 3 basic types of constraints: similarity, structure, and purpose. The operation of these constraints is apparent in laboratory experiments on analogy and in naturalistic settings, including politics, psychotherapy, and scientific research. The multiconstraint theory has been implemented in detailed computational simulations of the analogical human mind.

Pragmatics in analogical mapping.

Theories of analogical reasoning differ in the roles they ascribe to pragmatic factors as a source of constraints on analogical mappings. The multiconstraint theory as instantiated in the ACME model (Holyoak & Thagard, 1989a) claims that pragmatic constraints interact with structural and semantic constraints within the mapping stage itself, in addition to influencing pre-mapping and post-mapping stages. Participants in three experiments were asked to generate mappings between non-isomorphic analogs for which mappings for some elements were ambiguous on structural grounds. In all experiments, manipulations of participants' processing goals influenced their preferred mappings. At the same time, goal-irrelevant information contributed to many-to-one mappings (Experiments 1 and 2) and to the resolution of mappings that were ambiguous on the basis of goal-relevant information alone (Experiment 3). The qualitative pattern of results was successfully simulated using the ACME model, implementing the impact of processing goals as an inhibitory process of selective attention.

Remote analogical reminding.

Remote analogical reminding is hypothesized to occur when one episode is cued by another sharing similar themes but not similar object, character, or event descriptions. We report three experiments exploring this view. Subjects' remindings in Experiment 1 showed sensitivity to remote analogical similarity even though targets were encoded only briefly in an incidental learning paradigm. Experiment 2 subjects showed reliable remindings of remote analogs with study-test delays of up to 1 week. Experiment 3 demonstrated that remote analogical reminding effects are not an artifact of subjects' editing nonanalogical remindings. All experiments supported the hypothesis that human memory is sensitive to remote analogical similarity. We discuss the implications of these findings for memory models. Future progress requires the development of formal models that quantify factors relevant to reminding performance, such as reminding interference, transfer-appropriate processing, and domain expertise.

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.

Evoking the permission schema: the impact of explicit negation and a violation-checking context.

Cheng and Holyoak (1985) proposed that realistic reasoning in deontic contexts is based on pragmatic schemas such as those for assessing compliance with or violation of permission and obligation rules, and that the evocation of these schemas can facilitate performance in Wason's (1966) selection task. The inferential rules in such schemas are intermediate in generality between the content-independent rules proposed by logicians and specific cases stored in memory. In one test of their theory, Cheng and Holyoak demonstrated that facilitation could be obtained even for an abstract permission rule that is devoid of concrete thematic content. Jackson and Griggs (1990) argued on the basis of several experiments that such facilitation is not due to evocation of a permission schema, but, rather, results from a combination of presentation factors: the presence of explicit negatives in the statement of cases and the presence of a violation-checking context. Their conclusion calls into question both the generality of content effects in reasoning and the explanation of these effects. We note that Jackson and Griggs did not test whether the same combination of presentation factors would produce facilitation for an arbitrary rule that does not involve deontic concepts, as their proposal would predict. The present study tested this prediction. Moreover, we extended Jackson and Griggs' comparisons between performance with an abstract permission rule versus an arbitrary rule, introducing clarifications in the statement of each. No facilitation was observed for an arbitrary rule even when explicit negatives and a violation-checking context were used, whereas strong facilitation was found for the abstract permission rule under the same conditions. Performance on the arbitrary rule was not improved even when the instructions indicated that the rule was conditional rather than biconditional. In contrast, a small but reliable degree of facilitation was obtained for the abstract permission rule, with violation-checking content even in the absence of explicit negatives. The theory of pragmatic reasoning schemas can account for both the present findings and those reported by Jackson and Griggs.

Predictive and diagnostic learning within causal models: asymmetries in cue competition.

Several researchers have recently claimed that higher order types of learning, such as categorization and causal induction, can be reduced to lower order associative learning. These claims are based in part on reports of cue competition in higher order learning, apparently analogous to blocking in classical conditioning. Three experiments are reported in which subjects had to learn to respond on the basis of cues that were defined either as possible causes of a common effect (predictive learning) or as possible effects of a common cause (diagnostic learning). The results indicate that diagnostic and predictive reasoning, far from being identical as predicted by associationistic models, are not even symmetrical. Although cue competition occurs among multiple possible causes during predictive learning, multiple possible effects need not compete during diagnostic learning. The results favor a causal-model theory.

Mathematical problem solving by analogy.

We report the results of 2 experiments and a verbal protocol study examining the component processes of solving mathematical word problems by analogy. College students first studied a problem and its solution, which provided a potential source for analogical transfer. Then they attempted to solve several analogous problems. For some problems, subjects received one of a variety of hints designed to reduce or eliminate the difficulty of some of the major processes hypothesized to be involved in analogical transfer. Our studies yielded 4 major findings. First, the process of mapping the features of the source and target problems and the process of adapting the source solution procedure for use in solving the target problem were clearly distinguished: (a) Successful mapping was found to be insufficient for successful transfer and (b) adaptation was found to be a major source of transfer difficulty. Second, we obtained direct evidence that schema induction is a natural consequence of analogical transfer. The schema was found to co-exist with the problems from which it was induced, and both the schema and the individual problems facilitated later transfer. Third, for our multiple-solution problems, the relation between analogical transfer and solution accuracy was mediated by the degree of time pressure exerted for the test problems. Finally, mathematical expertise was a significant predictor of analogical transfer, but general analogical reasoning ability was not. The implications of the results for models of analogical transfer and for instruction were considered.

Learning subgoals and methods for solving probability problems.

We hypothesize that typical example problems used in quantitative domains such as algebra and probability can be represented in terms of subgoals and methods that these problems teach learners. The "quality" of these subgoals and methods can vary, depending on the features of the examples. In addition, the likelihood of these subgoal's being recognized in novel problems and the likelihood of learners' being able to modify an old method for a new problem may be functions of the training examples learners study. In Experiment 1, subjects who studied examples predicted to teach certain subgoals were often able to recognize those subgoals in nonisomorphic transfer problems. Subjects who studied examples demonstrating two methods rather than one exhibited no advantages in transfer. Experiment 2 demonstrated that if the conditions for applying a method are highlighted in examples, learners are more likely to appropriately adapt that method in a novel problem, perhaps because they recognize that the conditions do not fully match those required for any of the old methods. Overall, the results indicate that the subgoal/method representational scheme may be useful in predicting transfer performance.