Impact of indoor aroma on students’ mood and learning performance

Indoor environment has an appreciable impact on occupants' mood, health and performance. Among numerous indoor environmental components, indoor air quality is often considered to be one of the most crucial ones. While odor is a decisive factor for evaluating perceived indoor air quality, its effects - particularly the positive effects of pleasant aromas - on human responses and performance have yet to be revealed. In this study, experiments were conducted to investigate the effect of indoor aroma on students' mood and learning performance. Participants comprised 76 university students and they performed two learning tasks under one of the four odor conditions: "control (aromaless)", "rosemary", "lemon", and "peppermint." First, the way in which students sense the indoor aroma in a study space was investigated using several mood scales, including odor intensity, pleasantness, preference, acceptability, and impression. Second, the influence of indoor aroma on learning and memory performance was quantitatively assessed using a reading task and a verbal memory task. Lastly, the impacts of odor preference on subjective evaluation and performance were explored. This experiment showed that subjective evaluations were significantly different before and after olfactory adaptation, particularly in the rosemary condition. Of all three aroma conditions, the lemon aroma had the highest preference and led to the highest scores in the memory task. Although the significant impact of indoor aroma on learning performance was not detected, our results indicated that pleasant aroma has the potential to enhance students' mood and learning performance.