Surface stimulation of specific acupuncture points to reduce anxiety

A method of treating various anxiety-related disorders, such as Post-Traumatic Stress Disorder, panic attacks, or general anxiety disorder is disclosed. It has been found that the P1 midlatency auditory evoked potential of such patients undergoes increased amplitude and decreased habituation. Stimulation of three specific acupuncture points LR3, HT3, and PC6) on three different acupuncture meridians has been found to reduce the amplitude of the P1 potential using 20-minute periods of stimulation. Low frequency stimulation (around 5 Hz) was found to be most effective. Repeated periods of stimulation were also found to increase the effect of the treatment.

BACKGROUND OF THE INVENTION 
The present invention relates generally to the stimulation of acupuncture 
points to effect medical treatment. The present invention relates 
particularly to the stimulation of three acupuncture points to treat 
anxiety-related disorders. 
For more than three thousand years, Chinese physicians have used 
acupuncture to alleviate pain and treat a myriad of diseases. While the 
principles underlying the effectiveness of acupuncture as a treatment form 
are not yet completely understood, it has been well recognized that the 
stimulation of certain points on the human body has therapeutic effects. 
Such stimulation may be effected through the insertion of needles, 
activation of surface electrodes, or other means. 
The practice of acupuncture is based on the theory that certain lines 
running across the human body, referred to as meridians, are each 
associated with a certain organ. For example, the Lung Meridian 
(designated "L") runs from the tip of the thumb, along the forearm above 
the radius, and up to the shoulder. Other meridians include the Liver 
Meridian ("LR"), Stomach Meridian ("S"), Spleen Meridian ("SP"), Heart 
Meridian ("HT"), and Pericardium Meridian ("PC"). Along these meridians 
are certain points that, when stimulated, have certain effects (either 
therapeutic or deleterious) on the human body. Points along a meridian are 
designated by the meridian symbol combined with a number for that point; 
for example, the point on the Lung Meridian that lies just above the joint 
between the radius and the humerus is designated "L5". The stimulation of 
each point along a meridian is believed to have an effect different from 
the stimulation of other points along the same meridian. Thus according to 
acupuncture theory, the correct location of the proper meridian, and the 
correct location of the proper point along that meridian, is crucial to 
effecting a proper treatment. In particular, the traditional acupuncture 
treatment to relieve anxiety-related disorders requires the insertion of 
needles at two specific points, LR3 and HT3. A standard reference work 
identifying the acupuncture meridians and points, and the believed effects 
of stimulating many of those points, is Charles A. Meeker, Acupuncture for 
the Practitioner or Advanced Student (3d Ed. 1979), which is incorporated 
by reference herein. 
The use of acupuncture or the stimulation of acupuncture points for the 
general purposes of medical treatment and research has continued to the 
present day. The following prior art references demonstrate modern 
developments in this area: 
U.S. Pat. No. 3,908,669 issued to Man et al. is of interest for the prior 
art of devices using acupuncture in medical research and therapy. Man et 
al. discloses the use of electrically-charged needles rather than 
electrodes. 
U.S. Pat. No. 4,981,146 issued to Bertolucci discloses a nausea control 
device for mounting onto the human wrist. Electrodes stimulate the 
pericardium six (or PC6) acupuncture point. 
U.S. Pat. No. 5,269,304 issued to Matthews discloses an electro-therapy 
apparatus including at least two electrodes. Matthews suggests the 
efficacy of higher frequencies up to around 200 kHz, but also suggests 
employing slightly different frequencies on the two electrodes so as to 
achieve beat frequencies of 80 to 130 Hz. 
U.S. Pat. No. 4,055,190 issued to Tany discloses an electrical therapeutic 
apparatus for applying selected voltages and frequencies to various 
acupuncture meridians through needles. Suggested frequencies for each 
meridian are disclosed ranging from 500 Hz to 200 kHz. 
U.S. Pat. No. 5,417,706 issued to Chun is the most relevant to the present 
invention. Chun discloses a method of treating various types of baldness 
by inserting acupuncture needles into selected acupuncture points on 
multiple meridians. Chun identifies twelve particular acupuncture points 
on eight different meridians as effective in the therapy. 
It is known, therefore, in the prior art to employ surface stimulation over 
acupuncture points to alleviate various medical conditions. It is also 
known to employ multiple acupuncture points on multiple meridians to treat 
various conditions of baldness. It is also known that the stimulation of 
specific acupuncture points with needles may be used to treat anxiety and 
related disorders. In particular, the traditional prior art acupuncture 
treatment for anxiety and related disorders was the insertion of needles 
at two specific points, LR3 and HT3. 
Our studies have shown that, contrary to accepted acupuncture practice, the 
use of two acupuncture points alone is ineffective in reducing arousal in 
normal subjects and in treating patients with anxiety-related disorders. 
It was thus not recognized in the prior art that the effective treatment 
of Post-Traumatic Stress Disorder and other anxiety-related disorders 
requires that at least three acupuncture points be stimulated. Nor was it 
recognized that these three points may lie along three different 
meridians. Nor was it recognized in the prior art that the three specific 
points identified in the disclosed invention (HT3, PC6, and LR3) may be 
used in combination to effectively treat anxiety-related disorders. Nor 
was it recognized that a low electrode frequency of about 5 Hz is most 
effective in treating anxiety-related disorders. 
SUMMARY OF THE INVENTION 
The present invention is a method of treating various anxiety-related 
disorders, such as Post-Traumatic Stress Disorder, panic attacks, or 
general anxiety disorder. Patients suffering from such conditions 
typically experience severe reactions to relatively mild stimuli (for 
example, auditory stimuli). The present invention treats such conditions 
by stimulating three different acupuncture points. It has been found that 
the stimulation of three points on three different meridians, particularly 
the points LR3, HT3, and PC6, has an arousal-reducing effect on normal 
subjects and may have a therapeutic effect for sufferers of 
anxiety-related disorders. This effect is not seen when only the two 
points LR3 and HT3 are stimulated. The LR3 acupuncture point is roughly 
located on the top of the foot, 2 cm proximal to the margin of the first 
and second toes. The HT3 acupuncture point is roughly located on the 
inside of the elbow, midway between the medial end of the elbow crease and 
the medial epicondyle of the humerus when the elbow is fully flexed. The 
PC6 acupuncture point is roughly located on the wrist, 2 cm proximal to 
the midpoint of the wrist crease, between the tendons of the palmaris 
longus and the flexor carpi radialis muscles. 
Although treatment may be effected using acupuncture needles charged with 
an electrical current, surface electrodes may also be used. Both types of 
stimulus devices are well known in the prior art. Low frequency stimuli 
have been found most effective, operating at a frequency of about 5 Hz. 
In patients with anxiety-related disorders, the P1 midlatency auditory 
evoked potential undergoes increased amplitude and decreased habituation. 
The P1 potential is a positive wave recorded at the scalp occurring at a 
40-70 msec latency following auditory stimulation of the patient. This 
potential is a measure of reticular activating system output, that is, 
cortical desynchronization or arousal. The P1 potential is present during 
waking and REM sleep, but absent during drowsiness and slow wave sleep. 
The P1 potential is believed to have at least one subcortical source, 
specifically in the pedunculopontine nucleus (PPN), the cholinergic arm of 
the reticular activating system. 
The P1 potential is exaggerated in disorders which are characterized by 
hyperarousal, such as schizophrenia and anxiety disorder, and is absent or 
reduced in disorders characterized by hypoarousal, such as narcolepsy. 
Thus the amplitude of a patient's P1 potential following auditory 
stimulation may be measured as an indicator of the severity of the 
patient's anxiety-related disorder. A reduction in amplitude of the 
subject's P1 potential indicates a reduction in arousal in normal subjects 
and consequently indicates a reduction of anxiety in anxiety-disorder 
patients. Further information concerning the source of the P1 potential 
and its relationship to arousal level is found at N. B. Reese et al., The 
Pedunculopontine Nucleus-Auditory Input, Arousal, and Pathophysiology, 
Elsevier, Amsterdam 461-67 (1987), which is incorporated by reference 
herein. 
It has been found that the use of acupuncture needles or surface electrodes 
at the LR3, HT3, and PC6 points causes a statistically significant 
reduction in a subject's P1 potential. Thus stimulation at these three 
points is demonstrated to have a potentially therapeutic effect on 
patients suffering from anxiety-related disorders. A rebound effect 
immediately after cessation of the stimulation causes the amplitude of the 
P1 potential to rise initially but then taper off to an amplitude lower 
than that reached before stimulation was applied. It has further been 
found that electrodes or needles using low frequency stimuli, in the range 
of about 5 Hz, result in the greatest reduction in P1 potential amplitude. 
It has also been found that repeated treatments using low-frequency 
stimuli at the identified points results in a greater reduction in the P1 
potential amplitude than single treatments standing alone. 
The novelty of the present invention therefore resides in the recognition 
that effective reduction of the P1 potential may represent effective 
treatment of Post-Traumatic Stress Disorder and related disorders, and 
requires that at least three acupuncture points be stimulated. It is also 
significant that the three points are on three different meridians, and 
that the specific points identified (LR3, HT3, and PC6) have not in 
combination been identified as having this effect. It is further novel to 
use low frequency stimuli at about 5 Hz to achieve this therapeutic 
effect. In addition, it is novel that repeated treatments yield superior 
results over a single treatment standing alone. 
It is therefore an object of the present invention to provide for the 
treatment of anxiety-related disorders by stimulating three different 
acupuncture points. 
It is also an object of the present invention to provide for the treatment 
of anxiety-related disorders by stimulating acupuncture points on three 
different meridians. 
It is a further object of the present invention to provide for the 
treatment of anxiety-related disorders by the placement of needles or 
surface electrodes at the LR3, HT3, and PC6 acupuncture points in 
combination. 
It is an additional object of the present invention to provide for the 
treatment of anxiety-related disorders using needles or electrodes passing 
a relatively low-frequency current of about 5 Hz. 
It is a still further object of the present invention to provide for the 
treatment of anxiety-related disorders using multiple treatments of 
needles or surface electrodes. 
These and other objects and advantages of the present invention will be 
apparent from a consideration of the following detailed description of the 
preferred embodiments in conjunction with the drawings which are briefly 
described as follows:

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The preferred embodiment of the present invention may be described with 
reference to FIGS. 1-3. FIG. 1 shows the location of the Pericardium 
Meridian 10. The acupuncture point PC6 is shown at 12. FIG. 2 shows the 
location of the Heart Meridian 14. The acupuncture point HT3 is shown at 
16. FIG. 3 shows the location of the Liver Meridian 18. The acupuncture 
point LR3 is shown at 20. Acupuncture point PC6, shown at 12, acupuncture 
point HT3, shown at 16, and acupuncture point LR3, shown at 20, are 
stimulated with needles or surface electrodes while using the present 
invention as described below. 
To measure the effects of stimulating the LR3, HT3, and PC6 points and 
thereby confirm the results of the present invention, recordings of the P1 
potential were made of subjects sitting on a recliner with eyes open. The 
P1 potential was recorded in a standard fashion at the scalp from a vertex 
electrode referred to a frontal electrode, with correction for eye and 
muscle artifacts. Stimulation was delivered through earphones at a rate of 
0.2 Hz using rarefied click stimuli at 50 dB above hearing threshold. 
Separate tests were conducted using needles and surface electrodes. 
Electrical current was applied to the needles or surface electrodes using a 
TENS stimulator. The amplitude of the current was set by raising the 
amplitude until the patient experienced a detectable tingling sensation. 
The current was then applied in 20-minute treatment periods. It was 
discovered that the decrease in P1 potential amplitude was greatest when 
the frequency applied was about 5 Hz. A greater decrease in P1 potential 
amplitude was also observed when multiple 20-minute stimulation periods 
were used. 
In a first series of experiments, the subjects were exposed to conditions 
as described above using needles or surface electrodes and a current 
oscillating at 100 Hz. Only one 20-minute period of stimulation was 
applied during these experiments. The results of the experiments using 
needles are shown by the graph of FIG. 4, and the results of the 
experiments using surface electrodes are shown by the graph of FIG. 5. 
Both graphs depict the average amplitude of the Pi potential as measured 
during key sections of the experiment: control, which represents the P1 
potential of the subjects before any stimulation took place, the P1 
potential during the stimulation, the P1 potential during the period from 
1-20 minutes after the cessation of stimulation, and the P1 potential 
during the period 30-40 minutes after the cessation of stimulation. Four 
subjects were used in each of these experiments. 
The data from this first series of experiments demonstrates a statistically 
significant drop in P1 potential amplitude from that measured during the 
period 1-20 minutes after the cessation of stimulation to that measured 
during the period 30-40 minutes after the cessation of stimulation. A 
statistically significant drop resulted whether needles or surface 
electrodes were used. In particular, the p-value for these data points was 
0.0001 when needles were used and 0.004 when surface electrodes were used. 
P-values are a commonly used statistical indicator ranging from 0 to 1 and 
indicating the probability that random sampling would lead to a difference 
between sample means as large or larger than were actually observed. Thus 
the chance that the difference evidenced by the first series of 
experiments was simply the result of random sampling is less than one 
percent. The change in P1 amplitude value between the control period 
before the stimulation was begun and the 30-40 minute period after 
stimulation ended was found to not be statistically significant. 
In a second series of experiments, multiple stimulation periods were 
applied to test subjects using a low-frequency current of about 5 Hz. The 
normalized results of these experiments are shown in FIG. 6 as a function 
of a percentage increase or decrease in amplitude of the subject's P1 
potential compared to that measured before surface stimulation was begun. 
Data points plotted in FIG. 6 illustrate the relative P1 amplitude after 
the first 10 minutes of stimulation, after the second 10 minutes of 
stimulation, 1 minute after the first stimulation period ended, 10 minutes 
after the first stimulation period ended, twenty minutes after the first 
stimulation period ended, after the first 10 minutes of the second 
stimulation period, after the second 10 minutes of the second stimulation 
period, 1 minute after the second stimulation period ended, 10 minutes 
after the first stimulation period ended, and twenty minutes after the 
first stimulation period ended. For these experiments, 8 subjects were 
exposed to only the first stimulation period and 4 subjects were exposed 
to both the first and second stimulation periods. 
Statistically significant decreases in relative P1 amplitude were observed 
between the base amplitude and those amplitudes measured 10 minutes after 
the first stimulation period began, 20 minutes after the first stimulation 
period began, 10 minutes after the second stimulation period began, and 20 
minutes after the second stimulation period began. P-values for those 
differences were less than 0.01, 0.05, 0.01, and 0.01, respectively. Thus 
the use of the lower-frequency current yielded an improved reduction in P1 
amplitude, as did the application of the stimulation for multiple periods. 
The present invention has been described with reference to certain 
preferred and alternative embodiments which are intended to be exemplary 
only and not limiting to the full scope of the present invention as set 
forth in the appended claims.