Temporal profiles of averaged (N = 25) hemodynamic changes in the left and right hemispheres measured by TCD (A) and NIRS (B–D) during chewing of three different gums.

<p>In (A), the data obtained during putting the TO-gum on the tongue are also superimposed as gray lines. In the NIRS signals (B–D), ΔO₂Hb is shown in (B), ΔHHb in (C), and ΔcHb in (D). Data are represented as mean ± SEM every 1 min. A bold bar in each panel indicates the duration of the gum-chewing test. Statistical comparisons were performed between the control value (i.e., before chewing) and the value measured at each time point. Significant differences are represented by individual symbols: *, control vs. TO-gum; ^†, control vs. T-gum; ^$, control vs. C-gum. Statistically significant levels were set at P = 0.005 ( = 0.05/10) by one-way ANOVA and Bonferroni's correction for multiple comparisons.