6867_06_p771-776

THE JOURNAL OF ALTERNATIVE AND COMPLEMENTARY MEDICINE
Volume 13, Number 7, 2007, pp. 771–776
Mary Ann Liebert, Inc.
DOI: 10.1089/acm.2006.6203
Holotropic Breathwork: The Potential Role of a Prolonged, Voluntary Hyperventilation Procedure as an JOSEPH P. RHINEWINE, Ph.D.,1 and OLIVER J. WILLIAMS, B.A.2 ABSTRACT
Objectives: To pose the question of whether Holotropic Breathwork (HB), a prolonged, voluntary hyper-
ventilation procedure, might be useful in treatment of common psychiatric conditions such as anxiety and de-pressive disorders.
Design: This is a hypothesis-posing paper pertaining to a potential novel treatment.
Summary: The neurophysiology and psychology of hyperventilation are reviewed, including findings demon-
strating that hyperventilation leads to significant changes in central nervous system activity as measured byvarious technological means. Preliminary evidence suggesting efficacy for HB is reviewed. A tentative biopsy-chologic hypothesis is offered, suggesting a potential mechanism that may underlie putative therapeutic effectsof HB. Specifically, when HB is used in the context of ongoing psychotherapy, hyperventilation may facilitategeneralized extinction of avoidance behaviors, resulting in therapeutic progress. Individuals high in trait ab-sorption and social desirability who have failed to respond adequately to psychotherapy might be those mostlikely to respond to HB. Recommendations for future research directions examining the therapeutic potentialof HB are offered.
Conclusions: Further research using more sophisticated methodologies than have been used to date will be
necessary in order to confirm or refute the hypothesis that HB may be useful in treatment of psychiatric dis-orders.
INTRODUCTION
are consequently now part of standard treatments for anxi-ety disorders. Holotropic Breathwork (HB) is a novel, so- During the past few decades, voluntary hyperventilation matic, experiential psychotherapeutic procedure that in-
has been used in clinical psychology and psychiatry as volves a number of diverse elements including music, a means of triggering panic for diagnostic purposes and as supportive touch, and elective bodywork (i.e., manually ex- part of desensitization therapies for anxiety disorders.1,2 The erted pressure aimed at releasing muscular tension or procedure of voluntary hyperventilation has proven to be spasm), and instructions to breathe “deeply and mindfully” safe after medical screening for contraindicating condi- throughout the session.3 Sessions typically last much longer tions,1–3 and has been demonstrated across numerous stud- than talk-based psychotherapy sessions, usually ranging ies to be helpful in treatment of anxiety as a tool for diag- from 1 to 3 hours, terminated voluntarily by the client. Most nosis and desensitization.1 Such uses for hyperventilation elements of this treatment would appear to be best regarded 1Private psychotherapy practice, Portland, OR.
2Private holotropic breathwork practice, New York, NY.
RHINEWINE AND WILLIAMS
as representing “common factors” of psychotherapy;4 in- (30–45 Hz) responses to visual stimuli.14 Long-latency deed, a competing hypothesis to ours would be that HB in- (100–200 millisecond) auditory and somatosensory evoked volves nothing but a set of already-understood, placebo-like potentials have been found to be suppressed after merely 3 elements that induce a nonspecific and mild therapeutic ef- minutes of voluntary hyperventilation;13 similar reductions fect, much like that of a session of supportive psychother- were found in evoked responses measured by cerebral apy, massage, relaxation, or prayer. However, one element MEG.13 Direct-current MEG15 has yielded evidence of an of HB appears to be unique to this procedure, namely, that increase in mean global cortex excitability during hyper- of prolonged, deliberate overbreathing. This aspect of HB ventilation.15 Functional magnetic resonance imaging would appear to capitalize upon the effects of hyperventila- (fMRI) has demonstrated rapid decreases of up to 10% in tion on the central nervous system to facilitate development MR signal within 20 seconds of initiation of hyperventila- of a temporary, benign, and potentially therapeutic state of tion in areas of the frontal, occipital, and parietooccipital altered consciousness. The purpose of this paper is to pose cortex.16 These changes are thought to reflect differences in the hypothesis that HB may a useful therapeutic modality cerebral metabolic activity and/or vascular regulation in in treatment of psychiatric disorders. We will review phys- these regions during hyperventilation.16 Cerebral hemody- iologic and psychologic effects of hyperventilation, along namic measurement has shown that within 20–30 seconds with preliminary evidence suggesting efficacy of HB. We of voluntary hyperventilation, blood flow velocity decreases will then pose a tentative, biopsychologic hypothesis of the in cerebral arteries, along with increases in capillary pH, underlying mechanism of putative effects of HB, and offer suggestions as to future studies examining this treatment.
Unsurprisingly, given the extent of the neurophysiologic changes just summarized, hyperventilation also has beenshown to cause cognitive changes,18 and when prolonged,to induce subjectively altered consciousness that corre- NEUROPHYSIOLOGIC AND PSYCHOLOGIC
sponds temporally with the neurophysiologic changes.19,20 EFFECTS OF HYPERVENTILATION
Manifestations of altered consciousness emerging after ap-proximately 8 minutes of hyperventilation have included Hyperventilation is known to produce a characteristic se- ringing/roaring in the ears, clouded vision, and feelings of ries of behavioral and physiological changes associated with lightness, astonishment, and/or euphoria.19 More dramatic hypocapnia, a decrease in brain CO2 partial pressure changes in consciousness, including perceptual distortions (PCO2)5,6 and concomitant increase in pH known as respi- and subjective “visions,” have been reported after periods ratory alkalosis, meaning excessive alkalinity of arterial of hyperventilation exceeding 15 minutes.19 With regard to blood.6 Typical symptoms associated with respiratory alka- a whole-brain conceptual model, such phenomena may be losis include dizziness, palpitations, and tingling/numbness related to a “transient hypofrontality,”21 meaning a brief pe- of the extremities.5,7 These symptoms form the basis of ex- riod of unusually low activity in the frontal cortex that has posure procedures used in hyperventilation-enhanced treat- been hypothesized to underlie a number of other altered ment of anxiety disorders,1 because they are similar to so- states of consciousness,21 such as those found in half-asleep matic symptoms of anxiety. At the more extreme levels of states, meditation, exercise “highs,” and some drug-induced hypocapnia associated with prolonged hyperventilation, car- states. It has been posited recently that there may be simi- popedal spasms, meaning involuntary contractions of the lar underlying neurobiologic changes associated with some muscles of the hands and feet, often emerge.5 Such mani- altered states of consciousness.22 Our hypothesis is based in festations are known to be benign but are sometimes inter- part on the observation that prior research has found both preted by the individual as signs of grave physical mal- hypocapnia14,23 and certain anesthetic agents such as keta- functioning, leading to panic and consequent escalation of mine24–26 to alter oscillation patterns of ␥-range neuronal hyperventilation, the so-called “hyperventilation syn- activity (30–45 Hz), as will be discussed further herein.
Hypocapnia caused by hyperventilation has been demon- strated to induce changes in a range of neurophysiologic PRELIMINARY EVIDENCE OF CLINICAL
measures, including resting12 and evoked13,14 electroen- UTILITY OF HOLOTROPIC BREATHWORK
cephalographic (EEG) as well as magnetoencephelographic(MEG)13,15 potentials, along with functional neuroimag- Given the findings we have summarized thus far demon- ing16 and cerebral hemodynamics.17 Briefly, resting EEG in strating clear effects of hypocapnia on neurophysiologic hyperventilation has demonstrated slowing of brain activa- measures as well as subjective awareness, it would appear tion rhythms across the brain, with substantial increases in plausible that the prolonged, voluntary hyperventilation in- lower frequency, ␦- (up to 4 Hz) and ␪- (4–8 Hz) activity.12 volved in HB might have some effect on symptoms of psy- Visually evoked potentials have been shown to be altered chiatric disorders. What is at issue is whether such effects by voluntary hyperventilation, with increases in ␥-band may be salutary, detrimental, or insignificant.
HOLOTROPIC BREATHWORK
To date, few studies have examined empirically the ther- controlled but nonrandomized trial provides some evidence apeutic potential of HB. Only three studies appear to meet that nonverbal aspects of experientially oriented therapies commonly accepted minimum criteria of methodological so- are important to efficacy, and that HB may be a useful ad- phistication to be considered as constituting reliable empir- junct to experientially oriented verbal psychotherapies, par- ical evidence (that is, those showing clear aims and hy- ticularly for patients who have had many months of treat- potheses, standardized procedures, objective, quantitative ment with inadequate clinical response.
measures with adequate and reported psychometric proper- Pressman* conducted a controlled study of 40 participants ties, some degree of control of potential confounds, and sta- matched for gender, ethnicity, and age, ranging widely on tistical analysis of results), and only one of these has been these variables. Participants were recruited by advertisement published in a peer-reviewed journal.27 Holmes and col- at a counseling center that conducts psychologic and spiri- leagues (1996)27 compared HB with talk-based, experien- tual counseling services and workshops. The study examined tially oriented therapy (EOT). Participants were referred by effects of HB on mood state (measured with the Profile of a pool of clinicians who practiced EOT (such as Gestalt ther- Mood States30) and psychiatric symptomatology (measured apy). The authors examined two self-selected groups of 24 with the Brief Symptom Inventory31). Participants were as- participants each, well-matched on demographic variables signed, based on matching, either HB or music therapy, with and extent of prior psychotherapy treatment (mean 82.7 the latter including the same music and postural components months for the HB group and 55.8 months for the psy- of HB but omitting the voluntary hyperventilation and other chotherapy group); the HB group had experienced a mean accompanying components of HB. The music therapy group of 7.6 prior HB sessions compared with none for the ther- was offered debriefing as a substitute for the summary draw- apy-only group. Both groups were young to middle-aged ing that customarily concludes HB sessions. Both groups un- adults (mean 39.3 and 36.2 years, respectively), were pre- derwent one session of treatment every 2 weeks for a total dominantly female (19 of 24 for both groups), and all were of six sessions, and were assessed before and after the course white. The HB group underwent six monthly HB sessions of six sessions of treatment. Groups did not differ at base- as well as weekly EOT sessions. The psychotherapy-only line on mood state or psychiatric symptoms. The author group received only the weekly EOT sessions, but were found highly significant differences on all scales of the Pro- given an additional assessment after six additional sessions file of Mood States30 in the HB group compared to the mu- of psychotherapy as a control for the additional attention re- sic group, signifying that a greater degree of altered con- sciousness was induced in the HB group.* Furthermore, Both groups were assessed at three timepoints, once be- although both groups were found to show improvements in fore the 6-month treatment period, once at the end of 3 psychiatric symptomatology on the Brief Symptom Inven- months, and once at the end of 6 months. Measures of clin- tory,31 improvements were more consistent in the HB group, ical improvement were selected based on the aspects of func- suggesting that the HB group received greater psychologic tioning considered by the authors to be those most relevant benefit from the six treatment sessions than did the music to experiential and existential therapies, including Templer’s therapy group. No patients showed undesirable changes from Death Anxiety Scale,28 the Affiliation subscale of the Per- pre- to post-treatment scores. This study thus offers modest, sonality Research Form-E,29 the Abasement scale from the preliminary evidence that HB may be more psychologically Personality Research Form-E29 to measure self-esteem, and beneficial than a common-factors4-based music therapy, and an author-developed problems questionnaire that elicited the also provides additional evidence that, at minimum, the pro- top three problems for which participants were seeking treat- cedure does not appear to be detrimental to individuals seek- ment, rated for severity on a Likert-type scale. The HB group showed significantly greater changes over time on depen- Hanratty,† in a one-group, repeated-measures, pre/post- dent measures compared with the therapy-only group. Post- test designed study with a 6-month follow-up timepoint, ex- hoc analyses demonstrated that the HB group showed greater amined 44 participants at an international HB workshop.
reductions in death anxiety on Templer’s Death Anxiety Study participants constituted 30% of the English-speaking Scale28 and greater increases in self-esteem on the Person- workshop attendees; their mean age was 48.7 years. Partic- ality Research Form-E29 compared with the therapy-only ipants were mostly (73%) female, and of a high educational group, controlling for number of prior psychotherapy ses- level (100% had had some college; 51.5% held a master’s sions. Analyses including the additional assessment for thetherapy-only group after six additional sessions yielded sim-ilar results. Groups showed equal changes over time on the *Pressman TE. The psychological and spiritual effects of problems questionnaire, suggesting that although HB plus Stanislav Grof’s Holotropic Breathwork technique: An exploratory EOT was more helpful than EOT alone in the therapist-iden- study. San Francisco, CA: Saybrook Institute, 1993; unpublisheddissertation.
tified areas of death anxiety and self-esteem, HB augmen- †Hanratty PM. Predicting the outcome of Holotropic Breathwork tation did not result in additional improvement in patient- Using the High Risk Model of Threat Perception. San Francisco, identified problem areas. The authors comment that this CA: Saybrook Institute, 2002; unpublished dissertation.
RHINEWINE AND WILLIAMS
degree or higher). Dependent measures included the Telle- duction in objective psychiatric symptoms. Such experi- gen Absorption Scale32 and Marlowe-Crown Social Desir- ences are best conceptualized behaviorally as representing ability Scale33 to measure aspects of participants’ personal- generalized extinction of internal, covert, avoidance behav- ity, and the Positive and Negative Affect Schedule,34 iors on the part of the patient. A similar process has been Templer’s Death Anxiety Scale,28 and the Brief Symptom demonstrated recently using the N-methyl-D-aspartate Inventory31 to measure aspects of psychiatric and psycho- (NMDA) receptor agonist D-cycloserine administered logic distress. Participants received two HB sessions of ap- acutely after exposure treatment for anxiety disorders.35 proximately 3–4 hours’ length over the course of 1 week.
The NMDA antagonist ketamine has been implicated as At post-test, participants were found to show significant re- a potential antidepressant agent36–39 as well as a potentially ductions in negative affect as measured by the Positive and useful adjunct to treatment of substance abuse disorders.40 Negative Affect Scale,34 and significant reductions of psy- Studies using anesthetic agents in rat hippocampal tissue chiatric symptoms on the Brief Symptom Inventory.31 At 6- samples24–26 have demonstrated that such agents disrupt month follow-up (N ϭ 22), mailed questionnaires indicated ␥-range (30–45 Hz) oscillations thought to serve a “bind- that reductions in overall psychiatric symptoms were main- ing” or associative function among distant populations of tained, although reductions in Negative Affectivity were no neurons, which may account for the dissociative effects of longer significant, and Positive Affectivity actually dropped these drugs upon conscious awareness. Gamma activity oc- significantly. The author speculates that the latter result may curs throughout the human brain in areas understood to be be attributed to a global reduction in arousal induced by HB.
important to the state of subjective awareness, including the Participants were found to have elevated scores compared neocortex, hippocampus, and thalamus,24 and appears to to established norms on the Positive Symptom total of the play a role in temporal modulation (i.e., timing control of Brief Symptom Inventory31 at all timepoints, suggesting that action-potential generation across populations of neurons).24 they represented, at minimum, a mildly psychiatrically dis- Although unproven at this time, the neuronal binding func- tressed population. Interestingly, participants were also tion of ␥ oscillation has been hypothesized to help maintain found to score higher on the Tellegen Absorption Scale32 a normal state of consciousness in which activity across dis- and Marlowe-Crown Social Desirability Scale33 than the parate brain areas occurs in tandem, “associated” rather than norm for the general population, indicating that participants dissociated.24–26 If supported by future research evidence, in this study were unusually high in trait absorption and so- such a model would show that neuronal dissociation under- cial desirability. The author suggests that high trait absorp- lies psychologic dissociation. Similar disruptive effects on tion and social desirability may predict positive response to ␥ oscillations were found for anesthetic agents with diverse HB. This study represents further preliminary evidence that pharmacodynamics but similar effects on consciousness, in- HB may be psychologically beneficial, and specifically that cluding those that act on ␥-amino-butyric acid (in the cases it may reduce psychiatric symptoms in mild-to-moderately of thiopental, propofol, and morphine)25 as well as NMDA distressed, educated, white females.
Under hypocapnic conditions, rat hippocampal tissue samples also have shown significant alteration in patterns ofgamma oscillations.23 Like ketamine and other anesthetic HYPOTHESIZED MECHANISM OF ACTION
agents,25 the prolonged, voluntary hyperventilation involved OF HOLOTROPIC BREATHWORK
in HB may exert its primary action on consciousness via al-tering the temporal stability of gamma activity in key brain We have developed a tentative, biopsychologic hypothe- areas, consistent with effects on visually evoked ␥ responses sis of putative psychotherapeutic effects of HB, drawing on found during voluntary hyperventilation.14 Voluntary hy- laboratory findings in humans and animals concerning perventilation has been found to be associated with tem- hypocapnia, which we will describe now as follows. We be- porarily reduced MR signal in the frontal cortex that resolves lieve that the altered consciousness induced by prolonged, quickly upon cessation of hyperventilation.16 Disruption of voluntary hyperventilation as well as the “set and setting” stability of ␥ activity has been hypothesized to represent a elements of HB involve a process of exposure to feared, in- neurophysiologic correlate of psychologic dissociation.24–26 ternal, affective stimuli in the context of a supportive ther- Under conditions of psychologic dissociation, one would ex- apeutic setting, with resulting extinction of covert avoidance pect alterations in normal patterns of regional cortical acti- behaviors. This process of relatively sudden behavioral vation, particularly in the frontal lobes.21 Indeed, transient change is subjectively experienced by patients as “cathar- hypofrontality has been theorized to underlie a range of al- sis.” Individuals who are considered to be suffering from re- tered states of consciousness,21 all of which involve a de- fractory anxiety or depressive disorders, and/or those who gree of psychologic dissociation. Given that the frontal lobes may be conceptualized by their therapists as posing strong are involved in control and selective inhibition of cognition “resistance” to treatment, often experience fresh progress in and behavior, both hypocapnia and low-dose anesthetics psychotherapy after such experiences, with concomitant re- may cause a temporary weakening of the inhibitory action HOLOTROPIC BREATHWORK
of the frontal lobes upon cognition and related subjective though hypocapnia may be the ingredient that sets HB apart experience, resulting in disinhibition of previously avoided from purely common-factors-based4 interventions, hypocap- or “suppressed” internal stimuli.21,41 Thus, dissociation and nia alone is not likely to exert the same psychotherapeutic disinhibition may facilitate experiential exposure to feared internal representations. In the context of the supportivetherapeutic conditions of HB, including several “common-factors” elements of psychotherapy as described herein, suchexposure may result in extinction of the covert avoidance ACKNOWLEDGMENTS
behaviors and thereupon, resolution of the consequent be-havioral “resistance” that characterizes difficult-to-treat psy- This project was made possible in part by private fund- chiatric disorders. Such an account would explain the pre- ing administered by the John E. Mack Institute. The authors liminary results suggesting usefulness of HB specifically would like to thank the following individuals for reading among individuals who have had many months of psycho- and providing comments on early drafts of the manuscript: therapy with inadequate clinical progress.27 Alternatively, it Cindy Smith, M.D., Jon Emens, M.D., Pradeep Nagachan- is also possible that HB exerts psychotherapeutic effects via dran, M.D., Timothy Catlow, Psy.D., and Kristin Flegal, a more direct physiologic route, and that altered conscious- ness is epiphenomal and unimportant to any therapeutic ef-fects. Such an argument has been made in the case of puta-tive antidepressant effects of ketamine, which were foundto occur several days after full return to normal conscious- REFERENCES
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