EEG-Based Analysis of Neural Responses to Sweeteners: Effects of Type and Concentration

Abstract

Sweetness is a key dimension of sensory experience in food, and variations in the type and concentration of sweeteners can elicit distinct brain responses. In this study, electroencephalography (EEG) was employed to systematically evaluate neural activity elicited by different concentrations of sucrose solutions (1%, 3%, 5%, and 7%) and by non-nutritive sweeteners matched in perceived sweetness to a 7% sucrose solution (10% erythritol, 0.0133% sucralose, and 0.0368% stevioside). The results revealed that an increased sucrose concentration was associated with progressively weaker EEG signal intensity, suggesting that the brain can effectively distinguish sweetness intensity. Under iso-sweet conditions, different types of sweeteners induced significantly distinct EEG patterns, indicating that the nature of the sweetener modulates flavor perception at the neural level. Further analysis showed increases in both δ- and α-band power following sweet taste stimulation, with prominent activations observed in the frontal, parietal, and right temporal regions. These findings demonstrate the utility of EEG in detecting subtle differences in brain responses to sweeteners, offering new insights into the neural mechanisms underlying sweet taste perception.

Keywords: brain response; non-nutritive sweeteners; scalp electroencephalogram; sweeteners; taste.

Figure 1

(A) The distribution of 64 EEG electrodes and their division into different brain regions according to the 10–20 international system. (B) A schematic diagram of the EEG signal acquisition process under different sample stimulations.

Figure 2

Differential variance analysis of overall brain signal responses elicited by 8 stimuli (water, 1%, 3%, 5%, and 7% sucrose solutions, and three non-nutritive sweeteners). * p < 0.05, ** p < 0.01.

Figure 3

Brain rhythm wave responses elicited by 5 stimuli (water, 7% sucrose solution, and three non-nutritive sweeteners). a, b, c present statistically significant differences (p < 0.05).

Figure 4

PSD results of brain response to 7% sucrose solution between 1 and 30 Hz. The different colored lines represent EEG activity from distinct brain regions, with colors matched to those in Figure 1A.

Figure 5

Grand average brain response of one randomly selected subject to 5 stimuli: (a) water, (b) 7% sucrose, (c) stevioside, (d) erythritol, and (e) sucralose. Color coding is relative to the absolute maximum potential difference. The more towards red indicates higher signal strength, while the more towards blue indicates weaker signal strength.

Figure 6

ANOVA of different brain region responses to 5 stimuli (water, 7%, and three no-sugar sweeteners). * p < 0.05, ** p < 0.01.