Exploring the differences between five basic tastes and tasteless stimuli on brain responses in young adult males utilizing scalp electroencephalography

Abstract

Different tastes help people distinguish the nutritional content and potential harmful substances in food. Understanding the physiological and neural mechanisms of tastes, especially how the brain processes and decodes these taste signals, is essential for comprehending the nature of taste perception. This study aims to explore neural mechanisms of taste. Sixteen male university students participated, and electroencephalography (EEG) data were collected during 40 s exposures to five taste (i.e., sour, sweet, bitter, salty, umami) and one tasteless liquid stimuli. Analysis of power spectrum features for these stimuli was then conducted and quantitatively assessed. The findings reveal that the most sensitive EEG responses to taste stimuli occur in the alpha1 and alpha2 bands. Significant differences in EEG responses between taste stimuli and tasteless stimuli were observed around 1–3 s post stimulation. Notably, there is a double-hump response for alpha1 and alpha2. Temporal, occipital, and central lobes exhibited more pronounced differences. Brain topography maps revealed differences in alpha2 rhythm for the five basic tastes throughout the 1–3 s. These findings offer valuable insights into the relationship between taste perception and the brain’s detection and processing of taste stimuli, contributing substantial theoretical and practical value to fields including food science, sensory perception, and neurocognitive research.