The effects of anxiety on taste perception: The role of awareness

Prior research has suggested that perceived taste can vary depending on emotional state. However, the mechanism underlying this phenomenon remains unclear. Herein, two experiments were conducted to investigate whether emotional states influenced taste perception through mere evocation or cognitively through the awareness of evoked emotions. In Experiment 1, we investigated how the influence of anxiety on taste perception changed when awareness was focused on anxiety. Specifically, after watching videos that induced relaxation or anxiety, the participants were divided into two groups: one that focused their attention on their emotions and one comprising participants that did not. The sweetness, saltiness, sourness, bitterness, and pleasantness of coffee were then compared between the groups. In Experiment 2, we examined the influence of awareness directed toward emotions without emotional manipulation on taste evaluations. Here, by evaluating taste for visual stimuli, we focused on the influence of taste receptors on cognitive processing related to taste perception. The subsequent results suggest that sweetness perception is suppressed by the evocation of anxiety without awareness, whereas bitterness perception is enhanced only by anxiety with awareness. These findings indicate that the mechanisms by which emotional states affect taste perception may differ depending on taste quality. These results are discussed from the perspective of the biological significance of each taste.