Observation on effect of meridian stimulation on blood oxygenation level of brain by applying Near Infra Red Spectrum (NIRS)

Abstract Objective To observe the effect of stimulating Yintang ( EX-HN 3) and Băihui ( GV 20) with electroacupuncture (EA) on blood oxygenation level of brain and explore the feasibility of measuring the therapeutic effect of acupuncture by applying near infra red spectrum (NIRS). Methods Ten participants semi-randomly selected from 158 adults (random test sequence) were stimulated with EA at the acupoints of EX-HN 3 and GV 20. Verbal fluency task was conducted before and after acupuncture, and changes in blood oxygenation level of cerebral cortex were tested by applying NIRS. Quantitative data were processed with JMP 10.0.2 software, and changes in waveforms of blood oxygenation level of brain before and after treatment were compared by applying NIRS. Results The mean of reacting dose (integral value) of blood oxygenation level of cerebral cortex of the 158 adults in the verbal fluency task was 10.6 ± 1.1, and the mean of the whole reacting dose of blood oxygenation level of cerebral cortex at 1/2 period of time during the test (centroids value) was 46.8 ± 1.6. In the EA group, the mean of integral value and centroids value of 10 adults were 8.4 ± 5.1 and 54.7 ± 12.2 before EA while 9.8±3.5 and 41.2±6.7 after EA. The integral value and centroids value of the EA group were closer to the mean of all the subjects. Conclusion It was found by NIRS that the blood oxygenation level of cerebral cortex could be regulated in bidirectional way by stimulating EX-HN 3 and GV 20 with EA, and a further research on whether it directly related to EA is to be made.