The Effects of Neurovascular Reflex Points on Stress Induced Stimuli

Abstract

This study aims to examine the effectiveness of an Energy Medicine treatment protocol used in reducing emotional based stress, and will look specifically at the physiological effects caused by distressing stimuli, and the treatment outcome.

The experiment was conducted with three test subjects (1 male and 2 female participants, with ages ranging from 26 to 52 years) all in relatively good health. Subjects were seated in a comfortable chair during a 30-minute biofeedback session. The ProComp 5 Biofeedback Device and BioGraph Infinity software were used for measuring and recording the data.

This report presents the results of data collected for three different parameters: skin conductance (SC), blood volume pulse (BVP), and respiration rate (RR).

This study was performed in a Faraday cage at the California Institute for Human Science in Encinitas, California. The Faraday cage was chosen for the ability to sheild participants and equipment from electromagnetic interference.

For each participant, analysis was performed on a single session where the individual was asked to imagine a very emotionally stressful relationship, or aspect of that relationship. Participants were then asked to release the stimuli, and a six minute neurovascular (NV) reflex point holding technique was performed. With all three participants, there was an improvement in physiological response to the stimuli during treatment. As well, all three participants noted they felt more relaxed after the NV reflex points were held. Certain perameters returned inconclusive results, which may have been due to location and small sample size.

These results warrant further research to determine how holding NV reflex points can be beneficial for reducing different types of emotionally based stress. Future studies might include testing cortisol levels, as well as utilizing an electroencephogram (EEG) to monitor brain activity, both pre and post stimuli.

Based on the current findings, holding Neurovascular reflex Points can be considered an effective technique when experiencing stressful relationships.

Introduction and Objectives

Applied Psychophysiology

Applied psychophysiology is an “evolving scientific discipline involving understanding and modifying the relationship between behavior and physiological functions, by a variety of methods including non-invasive physiological measures” (Schwartz & Andrasik, 2008, p. 17).

Biofeedback, a subset of applied psychophysiology, is the monitoring of physiological functions through the use of non-invasive and usually electronic equipment, which has been designed to measure and record psychophysiological variables such as electroencephalography (EEG), magnetoencephalography (MEG), electromyography (EMG), skin conductance (SC), abdominal respiration (AR), respiration rate (RR), blood volume pulse (BVP), heart rate (HR), skin temperature (ST), and blood pressure (BP) to name those most frequently used (Peper, Tylova, Combatalade, Gibney, & Harvey, 2008). These physiological signals are used as a psychophysiological mirror back to the client, and serve to both inform and correct thought patterns and their associated physical responses (Peper et al., 2008).

The current study uses several of these psychophysiological variables including SC, HRV, LF, HF, BVP, HR, AR and RR in order to assess the benefits of holding NV reflex points on relationship stress. These methods were chosen for this study because of the ease of use and non-invasiveness to participants.

The first measurement type used in this study is skin conductance (SC), which is the measurement of electrodermal activity in the skin. Electrodermal activity is described as “the electrical properties of the skin as they correspond to the activity of sweat glands” and is best measured in the hands (Peper et al., 2008, p. 161). Interestingly, when an activation of the sympathetic nervous system occurs, the sweat glands will secrete perspiration “with a proportional increase in the electrical conductance of the skin as measured by the SC sensor” (Peper et al., 2008, p. 162). Skin conductance is considered a good physiological indicator of stress and arousal, making this method an excellent choice for this study. Skin conductance was utilized in achieving a baseline during the sessions, both before and after the stimuli was introduced.

The second type of monitoring used Photoplethysmography (PPG) in order to derive “heart rate information by measuring changes in blood volume in the arteries and capillaries, that correspond to changes in the heart rate” (Peper et al., 2008, p. 284). The sensor used for PPG utilizes an infrared light to detect changes in heart rate, via a light emitting diode (LED) placed on the middle finger tip (Peper et al., 2008). The LED light is absorbed by the hemoglobin in the blood cells, is backscattered and then reflected back by the tissues, in order to be picked up by the photodetector located in the PPG sensor (Peper et al., 2008). The PPG sensor detects the heart rate by measuring the volume of blood that passes through the tissues with each pulse, and this is what is known as the blood volume pulse (BVP) (Peper et al., 2008). Many factors influence and affect blood flow including cognitive factors such as vasoconstriction, or increased parasympathetic arousal, and; environmental factors including low temperatures, prescription drugs or illness to name a few. These must be considered when using BVP as a measurement tool (Peper et al., 2008). BVP was included in this study in order to highlight the effects of emotional stress on heart rate.

Lastly was respiration, as recorded by the use of an abdominal strain gauge, which monitors changes in the expansion and compression of the abdomen (Peper et al., 2008). Respiration shows the amount of breaths through the movement of the abdominal muscles (Peper et al., 2008). As the functions of the entire body are reliant on and related to breathing, measuring respiration provides data on breathing patterns, both during peaceful states, and stress induced states. Breathing patterns need to be observed by monitoring the frequency, intensity and duration of breaths (Peper et al., 2008). These breathing patterns are calculated in breaths per minute and referred to as respiration rate (Peper et al., 2008). Respiration rate was included in this study in order to provide data on the impact of stress on breathing patterns.

Neurovascular Reflex Points

Neurovascular (NV) reflex points were discovered by Chiropractor, Terrance Bennett, in the 1930’s (Frost, 2013). NV reflex points, which are located primarily on the head, are neurological activation sites that stimulate blood flow to the muscles, related organs, and glands (Frost, 2013). These activation sites were mapped by Bennett through injecting radioactive dye into patients while holding various points on their head, and examining via a fluoroscope, which areas of the body the blood flowed to (Frost, 2013).

NV reflex points can become switched off during stressful experiences. This can be due to a combination of physical, emotional, biochemical and environmental stressors (Frost, 2013). All these stressors can add up, causing one or more of these switches to shut off, similar to how a circuit breaker works in an electrical panel (Frost, 2013). By holding the neurovascular points, they can be switched back on (Frost, 2013). Holding NV reflex points also activates blood flow to the associated organ, along with the specific muscles that are paired with each organ; an association which was discovered by Dr. George Goodheart, DC, in the mid 1960’s (Frost, 2013).

To stimulate the NV reflex points, a light touch is used with the pads of the fingers, and points should be held until you feel the pulses synchronize, or heat is felt (Eden & Feinstein, 2008). In the event that neither pulsing nor heat is experienced, hold for 3 minutes (Eden & Feinstein, 2008). This simple procedure can help calm the stress response, providing an opportunity to evoke relaxation which leads to greater health.

Study Objective

The intention of this study is to demonstrate how a simple technique of holding two sets of neurovascular reflex points on the head, which is followed by one round of desensitization biofeedback through stimuli recall, may assist individuals in relieving stress and/or anxiety associated with difficult relationships.

A similarly based study, consisting of a randomized-controlled trial of single-session biofeedback training on performance anxiety and heart rate variability in musicians, found that “a single session of slow breathing was sufficient for controlling physiological arousal in anticipation of psychosocial stress associated with music performance, and that slow breathing is particularly helpful for participants with high levels of anxiety” (Wells, Outhred, Heathers, Quintana, & Kemp, 2012, p. 1).

In a further related study entitled Learned Cardiac Control with Heart Rate Biofeedback Transfers to Emotional Reactions, the results showed that short duration biofeedback training improved the regulation of heart rate, and that this learned ability will transfer to emotionally challenging situations at a later date without biofeedback (Peira, Pourtois, & Fredrikson, 2013).

Based on findings of the aforementioned two studies, it is hypothesized that holding two sets of NV reflex points will reduce the heightened physiological response experienced in stressful relationships. Secondly, it may provide a level of awareness to participants, of the negative physiological responses caused by stress which may lead to symptoms or disease.

Finally, this study proposes that participants will be less affected by reintroducing the stimuli after experiencing the NV treatment in combination with one round of desensitization biofeedback, as well as being able to use the NV reflex points themselves in future in order to reduce the physiological impact of stressful situations.

Methods

Study Design

Using the ProComp 5 Biofeedback Device, and BioGraph Infiniti software to process the raw data, the effects of three variables of the autonomic nervous system response were measured, which included sensors for blood volume pulse (BVP), skin conductance (SC) and respiration rate (RR).

Once the stressor was identified as physiologically challenging to the participant by using live data on the ProComp 5, the practitioner then employed an Eden Energy Medicine hands-on manual therapy for a total of 6 minutes. The technique, which specifies holding certain NV reflex points, involves placing the practitioner’s thumb and middle finger first on the main neurovasculars on the forehead along with triple warmer neurovasculars on the temples bilaterally; and secondly on the main neurovasculars on the forehead paired with neurovascular reflex points on the back of the head for the rhythms of Summer (panic) and Winter (fear). Once the manual therapy was complete, the participant was again asked to focus on the same stressful stimuli in order to measure the effectiveness of the treatment in mitigating the autonomic stress response.

Each participant was provided with a consent form and verbal instructions outlining the procedure for the study. Once all questions were addressed, the participant was asked to sign the consent form.

The session began with the participant being instructed to sit upright in a chair with their feet flat on the floor, both hands placed on top of a book, and palms of the hands facing up. The BioGraph Infiniti software was launched and the ProComp 5 Biofeedback Device was powered on. Next, the participant was set up under “new client” in the BioGraph Infiniti software in order to track their individual results. The parameters of measurement were defined in order to correctly capture the live data necessary for this study.

The sensors were attached to the participant in the following order: First by placing the respiration strain gauge sensor around the subject’s abdomen over the area of maximum expansion to improve signal range (Peper et al., 2008). The sensor band should be snug, “so that the end of exhalation is visible, and the sensor doesn’t become loose at the full exhalation but not so tightly that the free movement of the chest and abdomen would be prevented” (Peper et al., 2008, p. 227). Next, the dual SC sensors were prepared by putting a dab of Nuprep ECG & EEG Abrasive Skin Prepping Gel on the metal conductive part of each sensor. Sensors were placed on both the second phalange of the pointer finger, and ring finger, of the subject’s non-dominant hand. This setup allowed for monitoring the C6 and C8 dermatomes in the hand. Lastly, the PPG sensor for measuring BVP was positioned on the second phalange of the middle finger on the non-dominant hand.

After completing the sensor placements, the participant was asked to close their eyes, take several deep cleansing breaths, and relax. The biofeedback test was started by putting the software into record mode.

Next, the participant was informed to maintain breathing normally, and that once an acceptable baseline was confirmed by the practitioner monitoring the skin conductance data, the next instruction would be given.

After baseline was achieved, the first marker was set in the Biograph Infiniti software. Instructions were then given to the participant to bring to their mind a specific person in their life where the relationship is very stressful; perhaps thinking of events, feelings, conversations or memories that they associate with that person, whereby the relationship continues to impact them negatively. The participant was instructed to nod their head, once the stimuli was clearly visualized in their mind or felt in their body. After 15 seconds of visualization, a second marker was set in the software and the subject was instructed that a practitioner would begin the six-minute treatment of holding two sets of NV reflex points on the head.

The third marker was set in the software to indicate the beginning of the treatment. The practitioner then began by placing both middle fingers on the participants temples representing the Triple Warmer NV points, and both thumbs on the main neurovascular points located at the frontal eminences of the forehead. This position was maintained for approximately 3 minutes, or until pulsing or electrical heat was felt by the practitioner. Subsequently, the second set of points were held with the practitioner placing the middle finger and thumb of one hand back on the Main NV points, and palm of the other hand across the back of the participant’s head, covering the neurovascular reflex points for the rhythm of Summer (panic) and the Rhythm of Winter (fear). This position was also held for approximately 3 minutes, or until pulses or heat was felt by the practitioner.

At the end of the treatment, a fourth marker was set in the BioGraph Infiniti Software. The participant was asked to release the stimuli from their mind, and bring their conscious awareness back to the room, allowing any thoughts, feelings or memories of the stressful relationship to dissipate, and to relax and breathe normally. The participant was allowed to return to baseline utilizing SC as a visual confirmation, and a fifth marker was set to mark the SC baseline.

The participant was again asked to focus on the same stressful stimuli in order to measure the effectiveness of the NV treatment in mitigating the autonomic stress response. A sixth marker was set after instructions given and the participant was allotted 15 seconds to recall the stressor. After the 15 seconds had elapsed, instructions were given to release the stimuli from the participant's mind, and bring their conscious awareness back to the room, allowing any thoughts, feelings or memories to dissipate, and to relax and breathe normally. The seventh marker was set, and the participant was allowed to return to baseline a final time.

Once SC baseline was achieved, the experiment was concluded and the recording was stopped in the software.

After the experiment concluded, each participant was asked which of the following phrases best described their experience:

A. More relaxed (or less stressed) and centered after the NV reflex points were held.

B. Less relaxed (or more stressed) than before after the NV reflex points were held.

C. No change.

Subjects

The three participants used in this study range in age from 26 to 58 years of age, all in good health, and consisted of one man and two women. A fourth participant was released from the study after showing habitual rumination, and an inability to release the stimuli once engaged. Participants were instructed not to use recreational drugs in the seven days prior; and to refrain from ingesting any stimulants, such as caffeine or nicotine, at least 4 hours prior to the experiment. As required by the study design, subjects were also chosen based on experiencing current or reoccurring emotional stress in at least one primary relationship.

Equipment

The equipment chosen for this study was the ProComp 5 Biofeedback Device which is paired with BioGraph Infiniti software to record the raw data. The sensors used to capture the data consisted of a single abdominal respiration strain gauge, a PPG sensor and dual SC electrodermal sensors.

Outcome Variables

The dependent outcome variable for this study consisted of holding two sets of specific NV reflex points on the participant’s head, in order to test the theory that a reduction in physiological response would be experienced.

The independent outcome variables included the actual physiological changes that occurred during the experiment, as recorded by the three different sensors. Further independent variables to consider that may impact the data set include the small sample size (three participants), the bias towards female gender (2:1), the age range of participants, and the broad range of differing abilities of participants to control their physiology; ranging from no ability to advanced stress mitigation techniques (meditation, yoga, chi gong, etc.). The receptivity of the participants to the NV technique may also impact the efficacy, producing a nocebo result if there is a bias against energy medicine or the techniques used.

Results and Discussion

The results of the three sensors used for testing, being skin conductance (SC), blood volume pulse (BVP), and abdominal respiration (AR), showed an overall favorable result in using the NV reflex points to reduce the physiological response to a stressor. These results have been broken down into specific variables for discussion and include skin conductance (SC), heart rate (HR), heart rate variability (HRV), low frequency (LF), high frequency (HF), abdominal respiration (AR), and finally average respiration rate (RR).

Skin Conductance

In analyzing the data for SC, results revealed a notable increase in amplitude when the participant was asked to recall or visualize a stressful relationship, and then it slowly returned to baseline during the NV reflex point holds.

As depicted in figure 1 below, the second marker represents the point in time where the participant is asked to bring to mind a stressful relationship for approximately 15 seconds. A spike in SC shows the heightened emotional response at this marker.

Next, markers three to four represent the duration of the NV reflex treatment. Results show a decline in the SC signal, with the rate going even lower than the original baseline number.

Fig. 1

The SC data related to marker six indicates the point at which the stressor is reintroduced for 15 seconds, in order to facilitate a further desensitization to the stimuli. Interestingly, the stress response to the second introduction of the stimuli (marker six) seems to carry more emotional charge than the first response to the stressor (marker two), showing that the unpleasant memory continues to be significant to this individual. However, the participant also recovers much more quickly the second time (marker seven onwards), thus taking less time to return to baseline.

It can be determined from this graph that the participant benefited in a decrease in the emotional response to the stimuli, showing a benefit to holding NV reflex points when experiencing relationship stress, and was also able to recover more quickly when the stimuli was introduced a second time.

Heart Rate, Heart Rate Variability, LF and HF

This study looked at the results of heart rate variability (HRV), low frequency (LF) high frequency (HF), and heart rate (HR) in beats per minute, as it related to specific event markers. Instead of R-R intervals being measured here, it is the interbeat intervals that are measured (Schwartz & Andrasik, 2008).

To be clearer, heartbeats are analyzed with photoplethysmography (PPG). In the PPG signal, it is the steepest increase in the signal prior to the peak, that records a heartbeat. HRV, as depicted in figure 2 below, is the physical variation in the time interval between heartbeats. Referred to as R-R intervals, these beats are measured by the difference in the interval from R-wave to R-wave (Schwartz & Andrasik, 2008). If the intervals between heartbeats are fairly constant, then HRV is considered low, but when their length varies, HRV is considered to be high (Schwartz & Andrasik, 2008).

Fig. 2

(referenced from www.ouraring.com)

HRV is determined by looking at amount of variation in the intervals between heartbeats. Figure three shows an example of interbeat intervals in milliseconds.

Fig. 3

(referenced from www.ouraring.com)

To fully understand the data produced by examining the interbeat intervals, we must look at the relationship between HRV and the autonomic nervous system (ANS). The ANS regulates the heart, respiration rate and digestion through the parasympathetic branch (rest), and the sympathetic (activation) branch (Schwartz & Andrasik, 2008). Thus, the HRV can be considered an indicator that the parasympathetic branch is operational. Regulation of the parasympathetic branch lowers the heart rate and provides an ability for greater variability between successive heartbeats (Schwartz & Andrasik, 2008). Parasympathetic regulation causes almost immediate changes that affect only a few heartbeats at a time, after which the heart rate returns towards normal (Schwartz & Andrasik, 2008). A sympathetic response from the ANS raises the heart rate creating less probability for variability between consecutive heartbeats (Schwartz & Andrasik, 2008). Therefore, when the sympathetic branch is inactive and the parasympathetic branch is active, the heart rate is lower and HRV higher. Factors such as stress, rumination, and traumatic recall can lead to the withdrawal of parasympathetic activity, or to activation of sympathetic activity, where both create an elevated heart rate and lowered HRV.

Figure 4a (below) shows the overall HRV is chaotic and incoherent, as confirmed by the HR response (beats per minute) in figure 6 located on page 19 of this study. The HRV however, shows some degree of variability. There is a slight improvement in HRV located between markers three and four, where the NV reflex point treatment is being performed. The data suggests breathwork such as respiration biofeedback, meditation, or yogic breathing practices may greatly improve the physiological response in this particular participant.

Fig. 4a

Figure 4b below shows an expanded view between markers three and four, in order to better observe the HRV data.

Fig. 4b

It is important to note also the relationship between HRV and the respiratory cycle, whereby inhalation has a tendency to increase the heart rate, and exhalation tends to decrease it (Peper et al., 2008). Regular and rhythmic abdominal breathing improves HRV; whereby shallow, unrhythmic chest breathing will produce a decrease in HRV. Refer to figure 9, and figure 9 in the section on respiration (pages 21 and 22 of this study) to examine the correlation as noted.

Low frequency (LF) and high frequency (HF) signals, represented in normalized units, emphasizes the controlled and balanced behavior of the two branches of the autonomic nervous system (Malik, 1996). LF, measured between 0.04 and 0.15Hz, refers to a specific component of heart rate variability that “provides an index of sympathetic nervous system effect on the heart” (Peper et al., 2008, p.415). HF is measured between 0.15 and 0.40Hz of the spectral analysis, and “reflects the influence of the vagus nerve in modulating the sinoatrial node” in the heart (Peper et al., 2008, p.413).

Figure 5 below reveals more stable, relaxed LF and HF signals overall between markers three and four, where the practitioner was holding the participant’s NV reflex points. More specifically, the LF signal shows an increase in sympathetic activity, both prior to the treatment, and after the treatment, whereas the fluctuations in HF show a decreased parasympathetic activity, ultimately creating an increase in the HR. This finding is consistent with the visual observance of this particular subject, who had difficulty settling at both the beginning and end of the experiment.

Fig. 5

HR, derived from measuring BVP, is calculated at each heartbeat from the interbeat interval (IBI), which is the portion of time between two consecutive heartbeats (Peper et al., 2008). Figure 6 (below) reveals that an increase in HR, occurred when the participant was asked to relive an aspect of a stressful relationship, noted between markers one and three, and again between markers six and seven.

It is interesting to note that the HR shows a notable decrease in activity while the NV reflex points are being held, between markers three and four. This result validates the efficacy of the treatment in reducing the stress response in the cardiovascular system.

Fig. 6

Future studies may include holding an additional point, which is the NV reflex point for heart located at the top of the head. The addition of this NV reflex point may provide further benefit to the cardiovascular system when exposed to stress.

The heart rate response graph in figure 7 (below) shows a continued drop in beats per minute throughout the experiment, with the HR being at its highest at the beginning of the session. It can be suggested this result may have occurred due to a level of performance anxiety, or stress surrounding the anticipated procedure of the experiment.

Brief increases in the beats per minute around those markers representing when the participant was instructed to think of a stressful relationship (between markers two and three, and again between markers six and seven), indicates a physiological response by the participant to the stimuli.

Fig. 7

Respiration

Figure 8 (below) depicts the signal for abdominal respiration rate, which measures the relative amount of expansion that occurred during respiration (breathing). This particular subject took deep breaths while the negative stimuli was introduced, and then we can see rapid and shallow breathing during the NV reflex point treatment, indicating a heightened level of stress.

The data tells us this participant experienced a physiological response during the treatment phase of the experiment; possibly anxiety caused from the hands-on treatment, or perhaps an aversion to having someone in their personal space for an extended period of time. Surprisingly, between markers two and three, where the participant was asked to think about the stressful relationship, two deeper breaths were taken.

Noted between markers four and six, when the stimuli are reintroduced, we see the respiration rate declines, however shallow breathing continues, and indicates an inability to relax. This particular participant would benefit from respiration biofeedback sessions, as well as a discipline that would introduce breath control such as yoga or meditation; the same recommendation as previously mentioned in HRV.

Fig. 8

Figure 9 below, depicts the average respiration rate throughout the duration of the experiment. We can determine from this chart, that the number of breaths increased even during the initial portion of the experiment where the participant was asked to relax and be calm, indicating again a poor breathing pattern.

During the NV reflex point treatment (between markers three and four) the breaths per minute continued to increase. This increase is indicative of a physiological response, which may have been due in part to rumination on the stimuli, even though the participant was instructed to release the stressful situation from their mind. Alternatively, it could be as mentioned above, due to an aversion to touch, or having the practitioner in their personal space. This data correlates with the abdominal respiration data shown in Figure 8 above.

Fig. 9

Conclusion

This study sought to examine the effectiveness of an Energy Medicine treatment protocol that utilized holding two sets NV reflex points in order to mitigate the undesirable physiological response caused by imagining an emotionally stressful relationship.

In reviewing the skin conductance parameter, the results of the data shows that participants experienced a physiological stress response to thinking about a difficult relationship. Once the subjects were asked to release all thoughts and feelings of the stimuli, their SC signal returned to baseline. Lastly, the treatment produced a favorable result with a lower SC reading than the re-introduced stimuli after treatment.

The HRV on this small sample size (3 participants) showed that all three had difficulty relaxing, poor breathing patterns, a degree of anxiety surrounding the experiment, or an inability to fully release the stimuli.

The HR results, when looking specifically at pulse, shows a heightened sympathetic response. The pulse is very irregular, indicating a heightened physiological response by the cardiovascular system in this particular participant.

The HR chart, depicting beats per minute, showed a slow decline from the beginning of the experiment to the end, which indicates a parasympathetic involvement in regulating the heart during fast, shallow respiration. It also could very well indicate a present anxiety, or rumination on the stimuli.

Results of abdominal respiration show a heightened physiological stress response during the treatment phase of the experiment, as did the number of breaths per minute, which may be attributable to anxiety due to the physical contact of the practitioner, or perhaps a discomfort associated with the practitioner standing in their personal space for an extended period of time.

Overall, the findings of this study show an improved physiological response in skin conductance and heart rate response (beats per minute), during the NV reflex point technique. There was also some benefit seen in HRV results.

A brief interview conducted with each participant, returned an overall feeling of reduced stress after the session. It was noted in the post session interviews, that the Faraday Cage was in fact not a good location to conduct the experiment due to the small, dark and restrictive space inside, whereby all three participants reported feeling anxious and not at ease in these surroundings. Therefore, a large room with windows, in a quiet location, may return differing results, thus making location an important consideration for future studies.

Two of the three participants became more aware of the negative physical effects that their particular stressful relationship has on their physiology, as gathered from their session. All three stated they would use the NV reflex points in future stressful situations to help relax.

For future studies, it is recommended that participants should not be made aware of the stimuli subject material prior to the experiment, due to results which suggest that knowledge of the stimuli caused rumination to begin almost immediately after the session started. By not exposing the study design to the participants in advance, a more pure, unbiased response may be garnered. Future studies should also include a much larger sample size in order that HRV, with LF and HF could be more closely examined.

References

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