Matching Bias in Conditional Reasoning: Do We Understand it After 25 Years?

The Roles of Rule Type and Word Term in the Deductive Reasoning of Adults with and without Dyslexia

Despite its importance to everyday functioning, reasoning is underexplored in developmental dyslexia. The current study investigated verbal deductive reasoning on the Wason selection task, not previously used in dyslexia research despite its well-established pedigree. Reasoning rule was manipulated, with the conditional rules varying in the logical values presented. The word frequency and imageability of the word terms was also manipulated. Twenty-six adults with dyslexia and 31 adults without dyslexia completed Wason selection task problems. No group difference in reasoning accuracy or completion time was found. However, the participants were most accurate when reasoning with the rule type "If p, then not q" and least accurate with the rule type "If p then q". More trials were also answered correctly when the word terms were highly imageable but of average word frequency. These findings are in line with the general reasoning literature. Dyslexia status did not interact with either rule type or word term type. The study expands upon previous research by testing verbal deductive reasoning in dyslexia, highlighting the role of imageability in facilitating reasoning performance for all, regardless of the presence or absence of dyslexia. Implications for the design of educational materials are considered.

Stereotypical Questions: How Stereotypes About Conversation Partners Are Reflected in Question Formulations

In conversations, activated stereotypes about conversation partners can influence communicative behaviors. We investigate whether and how stereotypes about categorized conversation partners shape topic choice and the types of questions asked. In three experiments, participants imagined having a conversation. Gender or age stereotypes of the conversation partner were manipulated by means of a picture. Results show a higher likelihood of addressing conversation and question topics consistent with stereotypic expectancies about conversation partners. Moreover, stereotypes were reflected in subtle variations in question formulations. When questions address stereotype-consistent topics, they are likelier formulated with high-frequency adverbs and positive valence, while questions addressing stereotype-inconsistent topics more likely contain low-frequency adverbs and negative valence. In addition, Experiment 4 suggests that recipients are sensitive to detect that questions reflect stereotypes about themselves, which can influence the evaluation of the conversation and partner. We discuss the consequences of biased question asking for interpersonal conversation and stereotype maintenance.

Set-shifting and inhibition interplay affect the rule-matching bias occurrence during conditional reasoning task

The rule-matching bias is a common error during conditional reasoning tasks, which refers to a tendency to match responses with the lexical context in the conditional rule and leads to incorrect responses. Conditional reasoning is one of the higher-level cognitive abilities affected by many cognitive skills. We aimed to determine whether inhibition and set-shifting skills with rule-matching bias occurrence could be related and, if so, to what quantitative, at a statistically significant level. A total of 30 healthy university students aged 18 to 30 participated in this study. We used the Wason's Selection Task (WST) to measure conditional reasoning and investigated their inhibition and set-shifting skills with the Stroop and Wisconsin Card Sorting Test, respectively. Results showed a significant positive correlation between the number of correct responses to the Stroop test and the Wason Selection Card Test (p=0.614). There was a positive correlation between the number of correct responses to the Wisconsin Card Sorting Test and the Wason Selection Card Test (p=0.423). Participants with higher inhibition and set-shifting abilities showed better performance in the conditional reasoning test and lower rule-matching bias errors.

Reference Dependence in Bayesian Reasoning: Value Selection Bias, Congruence Effects, and Response Prompt Sensitivity

This work examines the influence of reference dependence, including value selection bias and congruence effects, on diagnostic reasoning. Across two studies, we explored how dependence on the initial problem structure influences the ability to solve simplified precursors to the more traditional Bayesian reasoning problems. Analyses evaluated accuracy and types of response errors as a function of congruence between the problem presentation and question of interest, amount of information, need for computation, and individual differences in numerical abilities. Across all problem variations, there was consistent and strong evidence of a value selection bias in that incorrect responses almost always conformed to values that were provided in the problem rather than other errors including those related to computation. The most consistent and unexpected error across all conditions in the first experiment was that people were often more likely to utilize the superordinate value (N) as part of their solution rather than the anticipated reference class values. This resulted in a weakened effect of congruence, with relatively low accuracy even in congruent conditions, and a dominant response error of the superordinate value. Experiment 2 confirmed that the introduction of a new sample drew attention away from the provided reference class, increasing reliance on the overall sample size. This superordinate preference error, along with the benefit of repeating the PPV reference class within the question, demonstrated the importance of reference dependence based on the salience of information within the response prompt. Throughout, higher numerical skills were generally associated with higher accuracy, whether calculations were required or not.

The Brain Structure and Intrinsic Characters of Falsification Thinking in Conditional Proposition Testing

Wason's selection task (WST) as a representative of the field of conditional proposition testing has been explored by multiple disciplines for more than 50 years, but the neural basis of its key falsification thinking remains unclear. Considering that the accuracy of individuals in WST has stability over time, we believe that falsification thinking has a specific brain structural basis and intrinsic neural characteristics. To test this hypothesis, we studied individuals who were able to complete the WST using T1-weighted MRI (using voxel-based morphology (VBM) analysis) and resting electroencephalogram (EEG) (using microstate analysis, which can reflect stable cognitive characteristics of individuals) techniques. First, VBM analysis found that, compared with the verification group, the gray matter volume (GMV) of the left inferior temporal gyrus and the right superior temporal region of the falsification group was larger, whereas the GMV in the cerebellum of the verification group was significantly larger than that of the falsification group. Subsequently, the results of the microstate analysis of the resting EEG data showed that the contribution of class A of the falsification group, which is closely related to the language network, is significantly higher than that of the verification group. Our structural MRI and resting EEG results consistently show that the structure and intrinsic activity pattern of the temporal lobe in individuals with falsification thinking are specific. Furthermore, the findings may provide potential insights into the role of the temporal lobe (which is also a brain region of language processing) in thought.

Looking behind: Turning cards in the selection task

Wason's selection task requires that one imagine which of four cards, each of which has a letter on one side and a number on the other, one would have to turn over to determine whether a statement about the cards is true or false. For example, one might see four cards showing T, H, 6, and 4 and be asked to say which card or cards one would have to turn over to determine whether a statement in the form of If a card has T on one side, it has 4 on the other is true. In the great majority of experiments with this task no cards are actually turned. This limits the conclusions that can be drawn from experimental results. In two experiments participants actually turned (had a computer turn) virtual cards so as to show what they contained on their originally hidden sides. Participants were given a monetary incentive to do well on the task, and they performed it, with trial-by-trial feedback, many times. Performance was much better than is typically obtained with the more common way of performing the task. Results also demonstrate the importance of the precise wording of the statement to be evaluated and how a misinterpretation could help account for a tendency for people to turn only a single card even when the turning of two is required. Results prompt several questions of a theoretical nature and are discussed as they relate to recent theoretical treatments of the selection task.

Théories à processus duaux et théories de l’éducation : le cas de l’enseignement de la pensée critique et de la logique

Plusieurs théories de l’enseignement de la logique et de la pensée critique prennent pour acquis que l’apprentissage théorique, celui des règles formelles par exemple, et son application pratique sont suffisants pour maîtriser les outils enseignés et pour prendre l’habitude de les mettre en usage. Toutefois, tout indique que cet enseignement n’est pas efficace, une conclusion supportée par plusieurs travaux en sciences cognitives. Approcher l’étude de la cognition évolutionnairement avec les théories à processus duaux permet une explication de ces insuffisances, tout en offrant des pistes pour aborder l’enseignement de la pensée critique et de la logique de manière plus efficace. Dans cet article, nous souhaitons présenter cette approche et explorer ces pistes de solution afin de faire quelques recommandations pédagogiques et mettre en place un cadre théorique. Nous présenterons un exemple d’application de ce programme de recherche avec la philosophie pour enfants.

Automatic–Heuristic and Executive–Analytic Processing during Reasoning: Chronometric and Dual-Task Considerations

Human reasoning has been shown to overly rely on intuitive, heuristic processing instead of a more demanding analytic inference process. Four experiments tested the central claim of current dual-process theories that analytic operations involve time-consuming executive processing whereas the heuristic system would operate automatically. Participants solved conjunction fallacy problems and indicative and deontic selection tasks. Experiment 1 established that making correct analytic inferences demanded more processing time than did making heuristic inferences. Experiment 2 showed that burdening the executive resources with an attention-demanding secondary task decreased correct, analytic responding and boosted the rate of conjunction fallacies and indicative matching card selections. Results were replicated in Experiments 3 and 4 with a different secondary-task procedure. Involvement of executive resources for the deontic selection task was less clear. Findings validate basic processing assumptions of the dual-process framework and complete the correlational research programme of K. E. Stanovich and R. F. West (2000).

Prior belief and polarity in multicue learning

We report two experiments in which participants are trained using a multicue probability learning (MCPL) task, which attempts to simulate the acquisition of expert judgement by experience in the real world. Participants were asked to predict performance in certain occupations given a profile of personality test results with trial-by-trial outcome feedback. Only some cues were relevant, and the polarity of the cues (positive or negative predictors) was unspecified. In addition, 25% of random noise was added to the feedback to simulate real world uncertainty. The main factor of interest was that the role of prior belief (determined in a separate study of stereotypes) interfered with the learning process. Experiment 1 failed to find any influence of prior belief in the cues that were irrelevant to the criterion being trained. However, in Experiment 2 people learned to use the relevant cues better when their effect conformed with rather than conflicted with prior belief. Both experiments showed strong effects of cue polarity, with positive predictors much more easily learned. The results are discussed with reference to the cognitive processes involved in MCPL and closely related tasks.

The Role of Negation in Conditional Inference

This paper addresses the issue of how negative components affect people's ability to draw conditional inferences. The study was motivated by an attempt to resolve a difficulty for the mental models theory of Johnson-Laird and Byrne, whose account of matching bias in the selection task is apparently inconsistent with Johnson-Laird's explanation of the double negation effects in conditional inference reported by Evans, Clibbens, and Rood (1995). Two experiments are reported, which investigate frequencies of conditional inferences with task presentation similar to that of the selection task in two respects: the presence of a picture of four cards and the use of implicit negations in the premises. The latter variable was shown to be critical and demonstrated a new phenomenon: Conditional inferences of all kinds are substantially suppressed when based on implicitly negative premises. This phenomenon was shown to operate independently of and in addition to the double negation effect. A third experiment showed that the implicit negation effect could be extended to the paradigm in which people are asked to produce their own conclusions. It is argued that these two effects can be explained within either the mental models theory or the inference rule theory, of propositional reasoning, but that each will require some revision in order to offer a convincing account.

The Influence of Linguistic Form on Reasoning: The Case of Matching Bias

A well-established phenomenon in reasoning research is matching bias: a tendency to select information that matches the lexical content of propositional statements, regardless of the logically critical presence of negations. Previous research suggested, however, that the effect might be restricted to reasoning with conditional statements. This paper reports two experiments in which participants were required to construct or identify true and false cases of propositional rules of several kinds, including universal statements, disjunctions, and negated conjunctions. Matching bias was observed across all rule types but largely restricted to problems where participants were required to falsify rather than to verify the rules. A third experiment showed a similar generalization across linguistic forms in the Wason selection task with only if conditionals substituted for universals. The results are discussed with reference to contemporary theories of propositional reasoning.

Facilitation and inhibition caused by the orienting of attention in propositional reasoning tasks

In an attempt to study the orienting of attention in reasoning, we developed a set of propositional reasoning tasks structurally similar to Posner's (1980) spatial cueing paradigm, widely used to study the orienting of attention in perceptual tasks. We cued the representation in working memory of a reasoning premise, observing whether inferences drawn using that premise or a different, uncued one were facilitated, hindered, or unaffected. The results of Experiments 1a, 1b, 1c, and 1d, using semantically (1a–1c) or statistically (1d) informative cues, showed a robust, long-lasting facilitation for drawing inferences from the cued rule. In Experiment 2, using uninformative cues, inferences from the cued rule were facilitated with a short stimulus onset asynchrony (SOA), whereas they were delayed when the SOA was longer, an effect that is similar to the “inhibition of return” (IOR) in perceptual tasks. Experiment 3 used uninformative cues, three different SOAs, and inferential rules with disjunctive antecedents, replicating the IOR-like effect with the long SOAs and, at the short SOA, finding evidence of a gradient-like behaviour of the facilitation effect. Our findings show qualitative similarities to some effects typically observed in the orienting of visual attention, although the tasks did not involve spatial orienting.

People Like Logical Truth: Testing the Intuitive Detection of Logical Value in Basic Propositions

Recent studies on logical reasoning have suggested that people are intuitively aware of the logical validity of syllogisms or that they intuitively detect conflict between heuristic responses and logical norms via slight changes in their feelings. According to logical intuition studies, logically valid or heuristic logic no-conflict reasoning is fluently processed and induces positive feelings without conscious awareness. One criticism states that such effects of logicality disappear when confounding factors such as the content of syllogisms are controlled. The present study used abstract propositions and tested whether people intuitively detect logical value. Experiment 1 presented four logical propositions (conjunctive, biconditional, conditional, and material implications) regarding a target case and asked the participants to rate the extent to which they liked the statement. Experiment 2 tested the effects of matching bias, as well as intuitive logic, on the reasoners' feelings by manipulating whether the antecedent or consequent (or both) of the conditional was affirmed or negated. The results showed that both logicality and matching bias affected the reasoners' feelings, and people preferred logically true targets over logically false ones for all forms of propositions. These results suggest that people intuitively detect what is true from what is false during abstract reasoning. Additionally, a Bayesian mixed model meta-analysis of conditionals indicated that people's intuitive interpretation of the conditional "if p then q" fits better with the conditional probability, q given p.

A levels of processing interpretation of dual-system theories of judgment and decision making

Recently there has been spirited disagreement about the merits of dual-system theories of higher cognition. I suggest that this dispute is very similar to the 1970s dispute between two-store theories of memory and levels of processing theory. The two-store or “box” theorists stipulated that short-term memory and long-term memory stores were quite dissimilar and therefore represented separate memory stores. Levels of processing theorists disputed the evidence for separate memory stores and asserted that memory was an epiphenomenon of the depth to which a stimulus was processed. I adopt the levels of processing approach to show how it can help clarify the phenomena previously described by dual-system theories. Furthermore, this proposed resolution to the controversy renders moot the serious disagreements about what features might characterize each of the two processes in dual-system theories.

Comprehension and computation in Bayesian problem solving

Humans have long been characterized as poor probabilistic reasoners when presented with explicit numerical information. Bayesian word problems provide a well-known example of this, where even highly educated and cognitively skilled individuals fail to adhere to mathematical norms. It is widely agreed that natural frequencies can facilitate Bayesian inferences relative to normalized formats (e.g., probabilities, percentages), both by clarifying logical set-subset relations and by simplifying numerical calculations. Nevertheless, between-study performance on "transparent" Bayesian problems varies widely, and generally remains rather unimpressive. We suggest there has been an over-focus on this representational facilitator (i.e., transparent problem structures) at the expense of the specific logical and numerical processing requirements and the corresponding individual abilities and skills necessary for providing Bayesian-like output given specific verbal and numerical input. We further suggest that understanding this task-individual pair could benefit from considerations from the literature on mathematical cognition, which emphasizes text comprehension and problem solving, along with contributions of online executive working memory, metacognitive regulation, and relevant stored knowledge and skills. We conclude by offering avenues for future research aimed at identifying the stages in problem solving at which correct vs. incorrect reasoners depart, and how individual differences might influence this time point.

Dual-Process Theories of Higher Cognition: Advancing the Debate

Dual-process and dual-system theories in both cognitive and social psychology have been subjected to a number of recently published criticisms. However, they have been attacked as a category, incorrectly assuming there is a generic version that applies to all. We identify and respond to 5 main lines of argument made by such critics. We agree that some of these arguments have force against some of the theories in the literature but believe them to be overstated. We argue that the dual-processing distinction is supported by much recent evidence in cognitive science. Our preferred theoretical approach is one in which rapid autonomous processes (Type 1) are assumed to yield default responses unless intervened on by distinctive higher order reasoning processes (Type 2). What defines the difference is that Type 2 processing supports hypothetical thinking and load heavily on working memory.

The Problem of Circularity in Evidence, Argument, and Explanation

A number of recent articles (Fiedler, 2011, this issue; Gigerenzer, 2009; Kriegeskorte, Simmons, Bellgowen, & Baker, 2009; Vul & Kanwisher, 2010) have highlighted seemingly circular arguments and explanations in psychological research, which suggests that the problem is rife within psychology. The article reviews the literature on circularity, and, in light of this, evaluates these recent examples from psychology to determine whether it is indeed circularity that is the underlying problem and to make suggestions for what paths improvements might pursue.

Evidence for an inhibitory-control theory of the reasoning brain

In this article, we first describe our general inhibitory-control theory and, then, we describe how we have tested its specific hypotheses on reasoning with brain imaging techniques in adults and children. The innovative part of this perspective lies in its attempt to come up with a brain-based synthesis of Jean Piaget’s theory on logical algorithms and Daniel Kahneman’s theory on intuitive heuristics.

The difference in spatiotemporal dynamics between modus ponens and modus tollens in the Wason selection task: an event-related potential study

High-density, event-related brain potentials (ERPs) were recorded to explore differences in spatiotemporal dynamics between modus ponens (MP) and modus tollens (MT) in the Wason selection task. Results showed that MP elicits a more positive P3b-like component than MT from 400 to 800 ms. MP appeared to occur earlier than MT in various stages of proposition testing, such as stimulus processing and response selection. ERP results showed that MT has a longer duration and more negative later negative component (LNC) than MP at 2,000 ms. This result suggests that MT occupies more cognitive resources than MP in the final stages of proposition testing. The short and small left frontal LNC obtained by MP implies examination of the expectable conclusion, whereas the long and large left frontal LNC elicited by MT may be involved in the retention operation of the card in working memory from the monitoring and inspecting putative conclusion in the later stages of proposition testing.

The compatibility heuristic in non-categorical hypothetical reasoning: inferences between conditionals and disjunctions

A new theory explains how people make hypothetical inferences from a premise consistent with several alternatives to a conclusion consistent with several alternatives. The key proposal is that people rely on a heuristic that identifies compatible possibilities. It is tested in 7 experiments that examine inferences between conditionals and disjunctions. Participants accepted inferences between conditionals and inclusive disjunctions when a compatible possibility was immediately available, in their binary judgments that a conclusion followed or not (Experiment 1a) and ternary judgments that included it was not possible to know (Experiment 1b). The compatibility effect was amplified when compatible possibilities were more readily available, e.g., for 'A only if B' conditionals (Experiment 2). It was eliminated when compatible possibilities were not available, e.g., for 'if and only if A B' bi-conditionals and exclusive disjunctions (Experiment 3). The compatibility heuristic occurs even for inferences based on implicit negation e.g., 'A or B, therefore if C D' (Experiment 4), and between universals 'All A's are B's' and disjunctions (Experiment 5a) and universals and conditionals (Experiment 5b). The implications of the results for alternative theories of the cognitive processes underlying hypothetical deductions are discussed.

In Search of the Elusive Initial Model

A key assumption of Mental Model theory ( Johnson-Laird & Byrne, 1991 , 2002 ) is that reasoners should use a minimal representation of the premises, called the initial model, in order to reduce the cognitive load involved in the processing of more than one model. However, there is no direct evidence for this postulate. In the following studies, we modified the ability of participants to process conditional (if-then) inferences in more complex ways by varying the degree of arbitrariness of the conditionals and by restricting the time allotted. Study 1 used premises with arbitrary relations with explicit negations in both terms in order to control for a possible matching strategy, with 9 s, 15 s, or unlimited processing time. Results show a significant number of initial model patterns, which increased with time. No evidence for use of a matching strategy was found. Study 2 involved arbitrary relations without negations, with 6 s or 8 s processing time. This study showed a significant increase in initial model patterns at the longer times. Study 3 used premises with familiar relations with either very limited processing times (5 s, 7 s) or an unlimited time condition. Results show very low numbers of initial model patterns in the three time conditions. Overall, these studies provide clear evidence that reasoners do use an initial model form of reasoning, and suggest that this is done mostly because of difficulty of processing more abstract content.

Large scale brain activations predict reasoning profiles

Deduction is the ability to draw necessary conclusions from previous knowledge. Here we propose a novel approach to understanding the neural basis of deduction, which exploits fine-grained inter-participant variability in such tasks. Participants solved deductive problems and were grouped by the behavioral strategies employed, i.e., whether they were sensitive to the logical form of syllogistic premises, whether the problems were solved correctly, and whether heuristic strategies were employed. Differential profiles of neural activity can predict membership of the first two of these groups. The predictive power of activity profiles is distributed non-uniformly across the brain areas activated by deduction. Activation in left ventro-lateral frontal (BA47) and lateral occipital (BA19) cortices predicts whether logically valid solutions are sought. Activation of left inferior lateral frontal (BA44/45) and superior medial frontal (BA6/8) cortices predicts sensitivity to the logical structure of problems. No specific pattern of activation was associated with the use of a non-logical heuristic strategy. Not only do these findings corroborate the hypothesis that left BA47, BA44/45 and BA6/8 are critical for making syllogistic deductions, but they also imply that they have different functional roles as components of a dedicated network. We propose that BA44/45 and BA6/8 are involved in the extraction and representation of the formal structure of a problem, while BA47 is involved in the selection and application of relevant inferential rules. Finally, our findings suggest that deductive reasoning can be best described as a cascade of cognitive processes requiring the concerted operation of several, functionally distinct, brain areas.

The Role of Working Memory Capacity in Multiple-Cue Probability Learning

Multiple-cue probability learning (MCPL) involves learning to predict a criterion when outcome feedback is provided for multiple cues. A great deal of research suggests that working memory capacity (WMC) is involved in a wide range of tasks that draw on higher level cognitive processes. In three experiments, we examined the role of WMC in MCPL by introducing measures of working memory capacity, as well as other task manipulations. While individual differences in WMC positively predicted performance in some kinds of multiple-cue tasks, performance on other tasks was entirely unrelated to these differences. Performance on tasks that contained negative cues was correlated with working memory capacity, as well as measures of explicit knowledge obtained in the learning process. When the relevant cues predicted positively, however, WMC became irrelevant. The results are discussed in terms of controlled and automatic processes in learning and judgement.

The initial representation in reasoning towards an interpretation of conditional sentences

All accounts of human reasoning (whether presented at the symbolic or subsymbolic level) have to reckon with the temporal organization of the human processing systems and the ephemeral nature of the representations it uses. We present three new empirical tests for the hypothesis that people commence the interpretational process by constructing a minimal initial representation. In the case of if A then C the initial representation captures the occurrence of the consequent, C, within the context of the antecedent, A. Conditional inference problems are created by a categorical premise that affirms or denies A or C. The initial representation allows an inference when the explicitly represented information matches (e.g., the categorical premise A affirms the antecedent "A") but not when it mismatches (e.g., "not-A" denies A). Experiments 1 and 2 confirmed that people tend to accept the conclusion that "nothing follows" for the denial problems, as indeed they do not have a determinate initial-model conclusion. Experiment 3 demonstrated the other way round that the effect of problem type (affirmation versus denial) is reduced when we impede the possibility of inferring a determinate conclusion on the basis of the initial representation of both the affirmation and the denial problems.

Preferences for different questions when testing hypotheses in an abstract task: positivity does play a role, asymmetry does not

Previous studies on hypothesis-testing behaviour have reported systematic preferences for posing positive questions (i.e., inquiries about features that are consistent with the truth of the hypothesis) and different types of asymmetric questions (i.e., questions where the hypothesis confirming and the hypothesis disconfirming responses have different evidential strength). Both tendencies can contribute - in some circumstances - to confirmation biases (i.e., the improper acceptance or maintenance of an incorrect hypothesis). The empirical support for asymmetric testing is, however, scarce and partly contradictory, and the relative strength of positive testing and asymmetric testing has not been empirically compared. In four studies where subjects were asked to select (Experiment 1) or evaluate (Experiments 2-4) questions for controlling an abstract hypothesis, we orthogonally balanced the positivity/negativity of questions by their symmetry/asymmetry (Experiments 1-3), or by the type of asymmetry (confirmatory vs disconfirmatory; Experiment 4). In all Experiments participants strongly preferred positive to negative questions. Their choices were on the other hand mostly unaffected by symmetry and asymmetry in general, or - more specifically - by different types of asymmetry. Other results indicated that participants were sensitive to the diagnosticity of the questions (Experiments 1-3), and that they preferred testing features with a high probability under the focal hypothesis (Experiment 4). In the discussion we argue that recourse to asymmetric testing - observed in some previous studies using more contextualized problems - probably depends on context-related motivations and prior knowledge. In abstract tasks, where that knowledge is not available, more simple strategies - such as positive testing - are prevalent.

Do people reason on the Wason selection task? A new look at the data of Ball et al. (2003)

Despite the popularity of the Wason selection task in the psychology of reasoning, doubt remains as to whether card choices actually reflect a process of reasoning. One view is that while participants reason about the cards and their hidden sides—as indicated by protocol analysis—this reasoning merely confabulates explanations for cards that were preconsciously cued. This hypothesis has apparently been supported by studies that show that participants predominantly inspect cards which they end up selecting. In this paper, we reanalyse the data of one such study, which used eye-movement tracking to record card inspection times (Ball, Lucas, Miles, & Gale, 2003). We show that while cards favoured by matching bias are inspected for roughly equal lengths of times, their selection rates are strongly affected by their logical status. These findings strongly support a two-stage account in which attention is necessary but not sufficient for card selections. Hence, reasoning does indeed affect participants’ choices on this task.

Regional cerebral blood flow increases during wakeful rest following cognitive training

Positron tomography was used to investigate modulations of brain activity during the so-called resting state that may occur due to a concurrent cognitive training. Twelve subjects were repeatedly scanned during resting periods and while solving logical problems containing a bias causing them to make reasoning errors. At experiment mid-time, eight subjects were trained to inhibit the reasoning bias so that their performance in solving logical problems dramatically increased afterwards, while the other four subjects were trained to logical reasoning only which did not help improving their performance. In the subgroup of subjects who increased their performance after training, we found that during the post-training resting periods, as compared to pre-training resting periods, brain activity increases in areas not belonging to the classical resting network, namely the midbrain, thalamus, peristriate, inferior frontal, and ventromedial prefrontal cortices. Strikingly, in this subgroup of subjects, these same areas were found to be also more active during post-training successful execution of the logical task, as compared to pre-training erroneous execution of the task. Such findings were not observed in the subgroup of subjects who did not improve their performance after training to logic only. These results indicate that the brain default mode is a dynamic state during which context dependent local increases of cerebral blood flow may occur on a short-term, likely for the consolidation of newly acquired knowledge.

Weighting of contingency information in causal judgement: evidence of hypothesis dependence and use of a positive-test strategy

Contingency is an important cue to causation. Research shows that people unequally weight the cells of a 2 x 2 contingency table as follows: cause-present/effect-present (A) > cause-present/effect-absent (B) > cause-absent/effect-present (C) > cause-absent/effect-absent (D). Although some models of causal judgement can accommodate that fact, most of them assume that the weighting of information is invariant as a function of whether one is assessing a hypothesized generative versus preventive relationship. An experiment was conducted that tested the hypothesis-independence assumption against the predictions of a novel weighted-positive-test-strategy account, which predicts hypothesis dependence in cell weighting. Supporting that account, judgements of hypothesized generative causes showed the standard A > B > C > D inequality, but judgements of hypothesized preventive causes showed the predicted B > A > D > C inequality. The findings reveal that cell weighting in causal judgement is both unequal and hypothesis dependent.