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An Intention Processing Network (IPN), involving the medial prefrontal cortex, precuneus, bilateral posterior superior temporal sulcus, and temporoparietal junctions, plays a fundamental role in comprehending intentions underlying action goals. In a previous fMRI study, we showed that, depending on the linguistic or extralinguistic (gestural) modality used to convey the intention, the IPN is complemented by activation of additional brain areas, reflecting distinct modality-specific input gateways to the IPN. These areas involve, for the linguistic modality, the left inferior frontal gyrus (LIFG), and for the extralinguistic modality, the right inferior frontal gyrus (RIFG). Here, we tested the modality-specific gateway hypothesis, by using DCM to measure inter-regional functional integration dynamics between the IPN and LIFG/RIFG gateways. We found strong evidence of a well-defined effective connectivity architecture mediating the functional integration between the IPN and the inferior frontal cortices. The connectivity dynamics indicate a modality-specific propagation of stimulus information from LIFG to IPN for the linguistic modality, and from RIFG to IPN for the extralinguistic modality. Thus, we suggest a functional model in which the modality-specific gateways mediate the structural and semantic decoding of the stimuli, and allow for the modality-specific communicative information to be integrated in Theory of Mind inferences elaborated through the IPN.

This article presents and evaluates a model to automatically derive word association networks from text corpora. Two aspects were evaluated: To what degree can corpus-based word association networks (CANs) approximate human word association networks with respect to (1) their ability to quantitatively predict word associations and (2) their structural network characteristics. Word association networks are the basis of the human mental lexicon. However, extracting such networks from human subjects is laborious, time consuming and thus necessarily limited in relation to the breadth of human vocabulary. Automatic derivation of word associations from text corpora would address these limitations. In both evaluations corpus-based processing provided vector representations for words. These representations were then employed to derive CANs using two measures: (1) the well known cosine metric, which is a symmetric measure, and (2) a new asymmetric measure computed from orthogonal vector projections. For both evaluations, the full set of 4068 free association networks (FANs) from the University of South Florida word association norms were used as baseline human data. Two corpus based models were benchmarked for comparison: a latent topic model and latent semantic analysis (LSA). We observed that CANs constructed using the asymmetric measure were slightly less effective than the topic model in quantitatively predicting free associates, and slightly better than LSA. The structural networks analysis revealed that CANs do approximate the FANs to an encouraging degree.

It is generally accepted that providing explanations during a task can facilitate problem solving performance in both adults and children. This paper aims to answer two important questions. First, can current theories of explanation be generalised to children’s explanations of self-generated answers? Second, what is the impact of such self-explanation on the development of children’s analogical reasoning skills? One-hundred-and-ten six- and seven-year-old children took part in seven sessions of matrix completion trials in one of five conditions: (1) explanation plus feedback; (2) explanation only; (3) feedback only; (4) practice; and (5) control. Analysis revealed that, contrary to existing theory, explanation of selfgenerated answers is not the most effective way to encourage the development of analogical reasoning. Rather, feedback on response accuracy is necessary for the attainment of heightened levels of performance. Results also indicate that children shift from using surface-level perceptual cues as a basis for their responses to a more sophisticated strategy involving an understanding of deeper-level relational structures. It is argued that these results support a metacognitive processing account of the development of analogical reasoning skills rather than an account emphasising changes in mental representations.

Successful performance on Wason’s (1960) 2-4-6 task is typically poor at approximately 20%. One reliable way to enhance solution rates is to use Tweney, Doherty, Worner, Pliske, Mynatt, Gross, and Arkkelin’s (1980) logicallyidentical Dual Goal (DG) version of the task, where participants are requested to discover two complementary rules, one labeled ‘Dax’ (the standard ‘ascending numbers’ rule) and the other labeled ‘Med’ (i.e., any other number triple). Despite the robustness of the DG effect, the mechanism by which the DG paradigm facilitates performance has remained obscure. The present studies assessed various theoretical proposals by providing participants examples of Med triples of varying ‘usefulness’, as indexed by the cues that they provided for establishing a relevant contrast class to the Dax rule. Results showed that the usefulness of the Med exemplar had a significant effect on successful discovery of the Dax rule. We propose that the present DG results can best be accommodated by extending Oaksford and Chater’s (1994) Iterative Counterfactual Model beyond its current focus on the standard single goal 2-4-6 task.

Two experiments are reported that tested core assumptions of the mental models theory of syllogistic inference (e.g., Johnson-Laird & Byrne, 1991) by examining inspection times for syllogistic components. Results supported mental models predictions of: (1) increased cognitive load across syllogistic figures, with differences in processing demand arising for BA-CB versus AB-BC problems for both conclusionevaluation and conclusion-production tasks; and (2) conclusion-order preferences across figures – again in both the evaluation and the production paradigms. These findings challenge views of figural biases as being confined to conclusion-production tasks (Geurts, 2003; Rips, 1994) and theories that reject the assumption of figure-induced cognitive load (Chater & Oaksford, 1999). Since figural effects are typically viewed as being indicative of premise-driven processing, these results are also inconsistent with proposals that premise-driven processing prevails in conclusionproduction, and conclusion-driven processing dominates in conclusion-evaluation (Morley, Evans, & Handley, 2004). The results also clarify the role of processing demands associated with conclusion validity: Valid conclusions were scrutinised less than invalid ones in the evaluation paradigm (as predicted by Hardman & Payne, 1995), supporting the notion that invalid syllogisms have at least two mental models. Although our specific results are not entirely consistent with recent models-based proposals, our basic findings remain broadly compatible with a models approach rather than alternative theoretical positions.

Evans’ (e.g., 1996) Heuristic-Analytic theory of reasoning in Wason’s selection task proposes the existence of implicit processes that direct attention to ‘relevant’ aspects of the problem and thereby determine card selections. This account also proposes that people pursue explicit rationalisations of relevance-determined choices. Our recent studies (e.g., Ball et al., 2003) have measured aspects of on-line attentional processing using eye-movement tracking and have supported the idea that card selections are driven by relevance and then subjected to rationalisation processes. For example, eyemovement data have revealed a reliable inspection-time imbalance between selected and non-selected cards. Our results, to date, however, have related to selection tasks with indicative contents. Here we report an eye-tracking study that involved deontic selection tasks. Various eye-movement measures revealed predicted differences in inspection times between selected and non-selected cards, with the magnitude of the effect being similar to that observed in studies of the indicative task. We discuss our results in relation to current theories of processing in the selection task.