Objective To observe the effect difference of electroacupuncture(EA) stimulation of Shenmen(HT 7) and Taiyuan(LU 9) on P 300 of event-related potentials(ERPs) in volunteer subjects

so as to explore functional specificity of acupoints in processing cerebral information.Methods Sixty healthy volunteer college students were randomly and equally divided into Shenmen(HT 7)group and Taiyuan(LU 9) group(30 persons/group).EA(2 Hz

1 mA) was applied to bilateral Shenmen(HT 7) and Taiyuan(LU 9) for 15 min.The ERPs were acquired by averaging EEG activity following Oddba Ⅱ auditory tone-double stimuli and brain electrical activity mapping(BEAM) acquired by means of Scan 4.5 collection and analysis system.Data were calculated and analyzed with SPSS 17.0 for Windows.After testing

the subjects were inquired about the perception for acupuncture stimulation and other sensations or psychological activities.Results Following EA stimulation of both HT 7 and LU 9

the amplitude of P 300 in the ERPs were significantly decreased in comparison with pre-EA stimulation in the same one group(P<0.01

P<0.05).No significant changes were found in the latencies of P 300 after EA stimulation of both HT 7 and LU 9(P>0.05).But

EA of HT 7 had a slightly stronger effect in shortening P 300 latency.With regard to the potential intensity distribution of BEAM

there were some differences between HT 7 and LU 9 groups.The high potential responses for HT 7 were found mainly in the occipital lobe

and in the left parietal lobe and the right temporal lobe

whereas those for LU 9 were found to mainly disperse in the left occipital lobe and the parietal lobe.Conclusion EA stimulation of HT 7 and LU 9 has a slight difference on lowering P 300 amplitude of ERPs

and may result in different distribution of the high potential responses in different lobes of the cerebral cortex in healthy subjects.The functional specificity of EA stimulation of different acupoints needs further study.