Analysis of developmental changes in lexical decision tasks: Differences between well elderly and university students

Resumen

The aim of this dissertation is to deepen on the analysis of positively skewed data through an ex-Gaussian fit. To study developmental changes in different cognitive components two samples of participants were selected: young university students and elder university students without cognitive impairment. The fit was performed based on empirical data (reaction times) obtained on a lexical decision task through experimental laboratory software. The results not only show that it is possible to adjust the distribution of reaction times to mathematical functions, but it also benefits us with a sensitive tool to estimate parameters or components that may reflect cognitive processes underlying language, aging and decisional processes within a temporal space. Finally, another issue of interest is the mathematical analysis of linguistic material and the effect of frequency. Specifically, the word frequency shows a scale-free distribution. This means that the number of words (P) with respect to its frequency (x) follows a power law. This form of distribution can be found in different fields like the topology of web pages and metabolic networks.