Experimental procedures and acupuncture manipulation
CORTEX
For VAG, in order to evoke needling sensations and avoid noxious stimulation, the subject's sensitivity and tolerance to needle manipulation were tested before performing acupuncture with fNIRS scanning. The results helped in choosing the depth of needle insertion and the force of needle manipulation to be used for data collection. Throughout the experiment, all dyads sat face‐to‐face during the entire process of the acupuncture manipulation in a quiet room. The whole experimental procedure included the following two sessions (Figure Experimental design and task procedures. (a) Acupuncture experiment paradigm. There are two conditions in the experiment: baseline (5 min) and acupuncture manipulation (2 min). At the end of the experiment, subjects were asked to evaluate the needling sensations. (b) Experimental setup. (c–e) Probe configuration. The integers on the cerebral cortex indicate the recording channels