Comparative effects of electroacupuncture and transcutaneous nerve stimulation on the human blink reflex.

The effects of low frequency (2 Hz) high intensity (10-12 mA) (electroacupuncture, EA) and of high frequency (100 Hz) low intensity (2 mA) (transcutaneous nerve stimulation, TNS) conditioning stimuli were studied on the nociceptive component (R2) of the blink reflex in normal volunteers. EA induced a progressive and moderate partially naloxone-reversible depression in the R2 response. In contrast, TNS induced a rapid and major depression in this reflex.