Impact of five basic tastes perception on neurophysiological response: Results from brain activity

The five basic tastes (sweet, salty, umami, sour, and bitter) perception plays a fundamental role in food choices. Nevertheless, how the perception of each basic tastes influence brain activity is still unknown. We investigated the effect of each taste on the brain activity of healthy adults using electroencephalography (EEG). For that, sucrose, sodium chloride, sodium glutamate, citric acid, and caffeine solutions were individually administered to 28 participants (18–25 years old). Self-reporting feedback was assessed using the 3-dimensional Self-Assessment-Manikin (SAM). The power density of the five frequency bands (delta, theta, alpha, beta and gamma) computed from the EEG signals was used to compare the five basic tastes. Significant differences (p < 0.05) were found for (1) beta waves: sweet vs umami, and salty vs umami; and for (2) gamma waves: sweet vs umami, and sweet vs bitter. The findings also indicate that sweet taste stimulated higher brain activity than umami in the gamma but not in the beta waves. Sweet, salty, umami and bitter tastes correlated with SAM responses. This study advances the understanding of brain response to taste stimuli, whilst improving the knowledge of these sensorial cognitive processes.