Personal comfort systems and cognitive performance: Effects on subjective measures, cognitive performance, and heart rate measures

Personal comfort systems (PCS) that warm or cool local body parts promise individual thermal comfort, energy saving and (metabolic) health in non-neutral thermal environments. However, research on work performance while using a PCS is scarce. We previously tested a PCS that warms the extremities and cools the head and reported that the PCS improved thermal comfort during a ramp of 17-23˚C but did not at a stable temperature of 25˚C. In the current study, its effects on cognitive performance, subjective measures and task-induced heart rate measures are investigated. Eighteen participants completed two randomized, eight-hour-long dynamic office scenarios: one is PCS scenario and another one is without PCS scenario. The results show warming the extremities slightly slowed reaction time for a simple task at 19˚C (p < 0.05) whereas it exerted no effect on complex task performance in 17-21˚C. At 25˚C however, cooling the head improved complex task performance (p = 0.053), which derived from participants’ effort increase, whereas it did not affect simple task performance. These findings suggest that the PCS’ effects on cognitive performance depended on the task type. Cooling the head, independent from its influence on thermal comfort, plays a significant role in complex cognitive performance in slightly warm conditions.