Fig 1.
CONSORT flow diagram.
Fig 2.
Time course of chewing-associated cortisol release.
The salivary cortisol concentration was measured at seven different stages (N = 12), which are described as follows: rest (before chewing), chewing (during chewing), immediately after chewing, and 10, 20, 30, and 60 min after chewing of taste and odour gum (TO-gum). Error bars indicate the 95% confidence interval. There was a significant difference in salivary cortisol concentrations at rest and those during gum chewing. *: vs. rest (P < 0.008 [0.05/6]), according to Friedman tests followed by Bonferroni’s correction for multiple comparisons.
Fig 3.
Flavour modulation of cortisol release during gum chewing.
A: The visual analogue scale of the tested gum odour component B: The visual analogue scale of the taste component C: Total saliva volume D: Cortisol concentration. Significant differences are represented by individual symbols. *: vs. T-gum; §: vs. O-gum; †: vs. C-gum; ‡: vs. Rest. Statistical significance was P < 0.013 (0.05/4) or 0.01 (0.05/5), according to Friedman tests followed by Bonferroni’s correction for multiple comparisons.
Fig 4.
The motivational bias of cortisol release during gum chewing.
The subjects were asked to chew a palatable (TO-gum, positive motivational outcome) and unpalatable (SL-gum, negative motivational outcome) gum. A: The visual analogue scale of odour B: The visual analogue scale of taste C: Total saliva volume D: Cortisol concentration Statistical significance was P <0.05, according to Wilcoxon signed-rank tests.