engleski

PERCEPTUAL SPEED OF CROATIAN RAILROAD ENGINEERS FROM 25 TO 59 YEARS OF AGE: EMPIRICAL FINDINGS AND IMPLICATIONS

A general decline in cognitive functions with age has a significant impact on professional functioning, especially for professional drivers, and it is dominantly explained by the age-related reduction of processing speed. Given the significant impact of processing speed decline in ageing railroad engineers on the safety of passengers and transport of goods, it is important to register the intensity of that decline, its possible specificities and to indicate its main causes. One of the most important aspects of processing speed is perceptual speed (PS) and therefore a study of PS age-related changes was conducted with the aim of investigating the intensity and possible specificities of those changes. The participants were 103 male drivers of the Croatian Railways, ages 25-59, assigned to 4 age groups, distinguished by specific functional characteristics of professional drivers. Two equivalent perceptual speed tests were applied individually. The participants’ task was to cross out as many of the target words in the context of distractor words in 60 seconds. Descriptive statistics indicates expected average PS values, with slightly positive asymmetric distributions and an optimal and homogenous variability. The average number of errors shows the expected very low value with very positive asymmetric distributions and homogenous variability. The effect of speed-accuracy trade-off was nonexistent. A statistically significant nonlinear PS decline with increasing age is evident, while there are no changes in inter- individual variability and number of errors. The results are discussed in relation to the theory of cognitive aging and empirical findings in the general population, with the implications on railroad engineers ageing process. Some of the key causes of the PS decline with age and possible interventions are reviewed.

perceptual speed ; aging process ; railroad engineers

This study is supported by the Faculty of Transport and Traffic Sciences of the University of Zagreb (Program of support for establishing of the research activities and groups PROM-PRO 997-19)