Older office workers are more resilient to mental fatigue

Mental fatigue, during or after a period of prolonged mental workload, is a common phenomenon in our everyday lives. Mentally fatigued people generally respond slower and less accurate to stimuli in their environment, which potentially leads to dangerous situations. Besides mental fatigue, increases in task demands also affect speed and accuracy. In the present study we examined whether younger and older adults adapt similar or different strategies to cope with mental fatigue and task load. After performing two alternating computer tasks of 120 minutes, younger and older office workers reported the same increase in subjective fatigue. However, we showed that older office workers (50-70 y) showed different patterns of decline in performance with time-on-task than younger office workers (18-30 y). Although both the older and the younger office workers became slower with time-on-task, we observed that during the writing task, the percentage of typed words that contained a mistake increased with time-on-task in the younger group, while there was no increase with time-on-task in the older group. The percentage of mistakes participants corrected also increased more with time-on-task in the younger group than in the older group. These results demonstrate that older office workers might be more resilient to mental fatigue than younger office workers.