Healthy ageing at work

Demographic ageing in the Western world means that the average age of the working population is increasing. This has major consequences for the labour process. Growing older is linked to physical and cognitive changes that can influence the performance of tasks. We are faced with an important challenge: to keep an ageing population healthy and deployable in the long term. One of the cognitive problems that employees experience is mental fatigue. Previous research shows that, after or during a period of mental workload, problems related to cognitive control arise. To prevent problems related to mental fatigue, we aim to find objective methods that could detect mental fatigue at an early stage, that is, before performance declines. Two groups of twenty-four participants, ranging in age from 18 to 30 years and 50 to 67 years, performed a set of two computer tasks for 120 minutes. The first task consisted in a visual search task, in which the participants had to click on a target stimulus, and the second task consisted in a working memory task, in which participants had to recall and type in sentences that were presented on the screen. At the beginning and at the end of the experiment the level of subjective fatigue was assessed using the activation-deactivation adjective checklist (AD ACL). During the experiment task performance, different physiological (i.e. brain activity, muscle activity, hart activity, and eye movements) and behavioral parameters (i.e. sitting behavior and keyboard and mouse use) were measured Results show that participants experienced a higher level of mental fatigue at the end of the experiment than at the beginning of the experiment. Additionally, participants made more mistakes on the computer tasks after a period of prolonged mental workload. Some participants seemed to change their strategy and were able to correct for their mistakes, while others showed a stable decrease in performance over time. Further analyses should point out what patterns in behavior and physiology can be related to the decrease in performance. The first results point to increased use of backspace during typing as an indicator of mental fatigue. Performance declines after a period of prolonged mental workload. The first results point to increased use of backspace during typing as an indicator of mental fatigue