Effects of verum acupuncture compared to placebo acupuncture on quantitative EEG and heart rate variability in healthy volunteers

Objectives: The aim of this single-blind randomized crossover study was to evaluate specific effects of manual acupuncture on central and vegetative nervous system activity measured by quantitative electroencephalography (qEEG) and heart rate variability (HRV). Design: Twenty (20) healthy volunteers (mean: 25.2 ± 3.6 years) were monitored simultaneously using a qEEG system and a 12-channel electrocardiogram recorder during verum acupuncture (VA) at acupuncture point Large Intestine 4 (Hegu) (LI4) or placebo acupuncture (PA) at a sham point. Results: In the EEG conduction of the occipital area, needle stimulation in VA increased α1-frequency significantly, and the ratio α1/θ was shifted to the benefit of α1 over all electrodes. The HRV parameters showed a significant increase of the low frequency/high frequency (HF) ratio during the first minute of stimulation in VA, indicating an initial increase of sympathetic activation. However, an increase of HF power in the minute after stimulation followed by a decrease in heart rate suggests delayed vagal activation. De qi (a sensation that is typical of acupuncture needling) occurred in 16 subjects during VA and in 9 volunteers during PA (80% versus 45%). Conclusions: Manual stimulation on LI4 seems to lead to specific changes in α EEG-frequency and in HRV parameters. A linear relationship between the HRV parameters and the α EEG band might point to a specific modulation of cerebral function by vegetative effects during acupuncture.