The relationship between temperamental dimensions and inhibitory control in early childhood: Implications for language acquisition

The present study investigates the latent organization of inhibitory control in children aged between 2;3 and 3;0 years. In addition, it explores the relationships between temperament dimensions - social orientation, motor activity, and attention -, inhibitory control and language. One-hundred-twelve typically developing children were evaluated with tasks for inhibitory control and lexical skills, while ratings of temperament and language were collected from their caregivers. A Confirmatory Factor Analysis reveals that inhibitory control seems to be best described by a unitary dimension. A Structural Equation Model suggests that 78 % of the variance in vocabulary is explained by a model considering the language observed measures, the three temperamental dimensions, and inhibitory control and in which both temperamental attention and the latent dimension of inhibitory control are significantly related to vocabulary. In addition, inhibitory control does not mediate the relationship between temperament and language.     

Conflict tasks and the diffusion framework: Insight in model constraints based on psychological laws

Formal models of decision-making have traditionally focused on simple, two-choice perceptual decisions. To date, one of the most influential account of this process is Ratcliff’s drift diffusion model (DDM). However, the extension of the model to more complex decisions is not straightforward. In particular, conflicting situations, such as the Eriksen, Stroop, or Simon tasks, require control mechanisms that shield the cognitive system against distracting information. We adopted a novel strategy to constrain response time (RT) models by concurrently investigating two well-known empirical laws in conflict tasks, both at experimental and modeling levels. The two laws, predicted by the DDM, describe the relationship between mean RT and (i) target intensity (Piéron’s law), (ii) standard deviation of RT (Wagenmakers–Brown’s law). Pioneering work has shown that Piéron’s law holds in the Stroop task, and has highlighted an additive relationship between target intensity and compatibility. We found similar results in both Eriksen and Simon tasks. Compatibility also violated Wagenmakers–Brown’s law in a very similar and particular fashion in the two tasks, suggesting a common model framework. To investigate the nature of this commonality, predictions of two recent extensions of the DDM that incorporate selective attention mechanisms were simulated and compared to the experimental results. Both models predict Piéron’s law and the violation of Wagenmakers–Brown’s law by compatibility. Fits of the models to the RT distributions and accuracy data allowed us to further reveal their relative strengths and deficiencies. Combining experimental and computational results, this study sets the groundwork for a unified model of decision-making in conflicting environments.     

Children’s attributions of beliefs to humans and God: cross-cultural evidence

The capacity to attribute beliefs to others in order to understand action is one of the mainstays of human cognition. Yet it is debatable whether children attribute beliefs in the same way to all agents. In this paper, we present the results of a false-belief task concerning humans and God run with a sample of Maya children aged 4-7, and place them in the context of several psychological theories of cognitive development. Children were found to attribute beliefs in different ways to humans and God. The evidence also speaks to the debate concerning the universality and uniformity of the development of folk-psychological reasoning.