The ability to estimate and discriminate quantities is of early onset in the development and prior to the acquisition of a symbolic numerical system. The performance on tasks of discrimination is modulated by the number ratio that differentiates the sets, so that smaller reasons result in slower and less effective comparisons. The objective of the present study is to analyze the precision and speed by which 4 and 6 year old children discriminate between two quantities based on the number ratio that distinguishes them. Method: a discrimination task of non-symbolic quantities (ad hoc) was given to 60 children from 4 and 6 years old in the city of Buenos Aires, Argentina. A mixed ANOVA design was carried out to analyze the amount of hits and reaction times (RT) according to age, and the number ratio that differentiates the groups. The Bonferroni contrast test was used to detect the differen...

The aim of this work was to study the relationship between working memory, sustained attention and explanatory inference generation in expository texts comprehension. To this end, 120 undergraduate students read two expository texts from natural sciences and completed an inference generation questionnaire, along with four verbal working memory tasks and two sustained attention tasks. The results showed that the executive component of verbal working memory has a direct effect on inference generation, while sustained attention and information storage in verbal working memory have an indirect effect mediated by the executive component. This supports the idea that individual differences in inference generation are related to individual differences in working memory, and also to individual differences in the ability to sustain attention.

Background: Mechanical reasoning (MR) is the ability to identify the components of a system and understand how they interact in order for the system to work. Different mechanical systems, such as those of wheels and gears, require different types of reasoning. Objective: This study seeks to analyze the relationship that working memory (WM) and processing speed (PS) have with MR. Method: One hundred seventy-three (173) university students were assessed through the DAT test which consisted of 30 MR problems, the symbol search subtest of the WAIS-III battery for assessing the PS, and the BIMET-V and BIMET-VE batteries to evaluate the WM verbal and visuospatial components. Results: Regression analyses showed that the proposed variables do not predict the performance in gear problems, while the visuospatial WM and the PS predict the performance in wheel problems. Discussion: The results sugge...