Analgesia Is Enhanced by Providing Information regarding Good Outcomes Associated with an Odor: Placebo Effects in Aromatherapy?

Figure 4

Total respiratory time ((a), 𝑇_tot) and tidal volume ((b), 𝑉_𝑇) during the condition without painful stimulation (no-pain condition), the painful stimulation with no treatment (control), and the painful stimulation with lavender-odor or no-odor treatment in the informed and not-informed groups. *𝑃<0.05, **𝑃<0.01, significant difference from the no-pain condition. ^†𝑃<0.05, ^††𝑃<0.01, significant difference from no treatment.

(a)

(b)