Biomedical subjects

Francisco J Abad

Publications and source records attributed to Francisco J Abad.

3 recordsLinked to original sources

PubMed2006

Generational changes on the draw-a-man test: a comparison of Brazilian urban and rural children tested in 1930, 2002 and 2004.

Although gains in generational intelligence test scores have been widely demonstrated around the world, researchers still do not know what has caused them. The cognitive stimulation and nutritional hypotheses summarize the several diverse potential causes that have been considered. This article analyses data for a sample of 499 children tested in 1930 and one equivalent sample of 710 children tested 72 years later, the largest gap ever considered. Both samples comprised children aged between 7 and 11 who were assessed by the Draw-a-Man test in the city of Belo Horizonte, Brazil. Further, one additional sample of 132 children was assessed in 2004 in a rural area very similar in several diverse factors to the 1930 urban sample. The results are consistent with both the cognitive stimulation and the nutritional hypotheses.

Age Factors↗

PubMed2006

Complex span tasks, simple span tasks, and cognitive abilities: a reanalysis of key studies.

There is great interest in the relationships between memory span tasks and cognitive abilities. However, the causes underlying their correlation remain unknown. In the present article, five key data sets were reanalyzed according to two criteria: They must consider complex span tasks (so-called working memory [WM] tasks) and simple span tasks (so-called short-term memory [STM] tasks), and they must comprise cognitive ability measures. The obtained results offer several points of interest. First, memory span tasks should be conceived from a hierarchical perspective: They comprise both general and specific components. Second, the general component explains about four times the variance explained by the specific components. Third, STM and WM measures are closely related. Fourth, STM and WM measures share the same common variance with cognitive abilities. Finally, the strong relationship usually found between memory span tasks and cognitive abilities could be tentatively interpreted by the component shared by STM and WM--namely, the capacity for temporarily preserving a reliable memory representation of any given information.

Aptitude↗

PubMed2002

Null sex differences in general intelligence: evidence from the WAIS-III.

There is an increasing number of studies claiming that the sex differences in general intelligence are "real." The empirical evidence is based on the summation of the standardized sex differences in several cognitive batteries. However, the scientific construct of general ability rests on the correlations among test scores, rather than on their summation. The latter (ability in general) is an arbitrary variable, not a scientific construct. General ability is not a function of any particular cognitive test, but a source of variance evidenced by the correlation between several diverse tests, each of which reflects general ability (g) to some extent, but also group factors and test specificity. Because there are important educational, economic, and social consequences of a group difference in general ability, it is especially germane to evaluate the possibility of an average sex difference in its proxy measures, such as IQ. The Spanish standardization of the WAIS-III is analyzed in the present study. The sample was made up of 703 females and 666 males, aged 15-94, drawn as a representative sample of the population in terms of educational level and geographical location. Although a male advantage of 3.6 IQ points is observed, the difference is in "ability in general," not in "general ability" (g). Given that the main ingredient of the strong association between IQ and a broad range of social correlates is g, and given that there is no sex difference in g, then the average IQ sex-difference favoring males must be attributed to specific group factors and test specificity.

Adult↗