Role of fNIRS technology in observing the effect of needling Hegu (LI 4) on the functions of prefrontal cortex in healthy volunteers

Objective

To observe the effect of needling Hegu (LI 4) on functions of the prefrontal cortex using the functional near infrared spectroscopy (fNIRS).

Methods

A total of 12 healthy volunteers were randomly assigned to an acupuncture group (n=6) and a control group (n=6). The control group received no intervention. The acupuncture group received needling Hegu (LI 4) on the right side. The real-time concentration changes of oxygenated hemoglobin (HbO₂), deoxygenated hemoglobin (d-Hb) and total hemoglobin (t-Hb) in the prefrontal cortex were recorded using the fNIRS, allowing for effect analysis of needling Hegu (LI 4) on the functions of the prefrontal cortex.

Results

Compared with the control group, the HbO2 and t-Hb concentrations were increased in the acupuncture group and there were between-group statistical significances (both P<0.05). There was no between-group statistical significance in d-Hb concentration (P>0.05).

Conclusion

Needling Hegu (LI 4) can extensively activate the prefrontal cortex and therefore has significant effect on the functions of the brain’s prefrontal cortex.