Cognitive ‘compensation’ by workloads in a fixed time-frame and thermoneutral environments: A pilot study

Abstract

To investigate cognitive changes under different workloads in thermoneutral environments, experiments were carried out on 15 participants. A 30-minute n-back task was utilized to produce three workloads. Three mental scales were completed to acquire the emotion, fatigue and mental workload of subjects. Meanwhile, the skin temperature, critical flicker frequency (CFF) was acquired, and the cognitive performance index (CPI) of n-back task was calculated. Results showed that the CPI was reduced significantly as the workloads were elevated from low to high level. Besides, under the high workload, the positive emotion was surprisingly increased (p < 0.05), and participants reported lower fatigue (p < 0.05). Furthermore, both local and mean skin temperature were negatively correlated with workloads, although under the high workload, the skin temperature was reduced significantly. Finally, the CFF was reduced significantly after low and moderate workload, but surprisingly it rose after high workload and was greater than when under lower workloads (p < 0.05). Results of this study revealed that the cognitive performance was not reduced under high workload in a fixed time frame, which was in accordance with changes in emotion, fatigue, perceived workload, the skin temperature and CFF, implying that the high workload might have produced a compensatory effect on cognitive attenuation in this experimental frame.