The individual difference and non-repeatability in acupuncture have not only restricted the development of acupuncture, but have also affected the specificity of acupoints.

As reported in a recent study published in Neural Regeneration Research (Vol. 8, No. 28, 2013), acupuncture at Neiguan (PC6) was performed using a custom lifting- and thrusting-controlled machine.

A frequency of 1, 2, or 3 Hz and duration of 5, 60, or 180 seconds were used to observe cerebral blood flow and ratio of infarct volume recovery.

An orthogonal design was used to sift the optimal parameter of Neiguan acupuncture. Experimental results showed that stimulation at Neiguan with a frequency of 1 Hz and long duration of 180 seconds or 2/3 Hz and long duration of 5/60 seconds significantly increased cerebral blood flow and decreased the ratio of infarct volume.