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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
Adjunct to Psychotherapy
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 by
various 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 effects
of HB. Specifically, when HB is used in the context of ongoing psychotherapy, hyperventilation may facilitate
generalized 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 most
likely to respond to HB. Recommendations for future research directions examining the therapeutic potential
of 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.
771
INTRODUCTION
D
uring the past few decades, voluntary hyperventilation
has been used in clinical psychology and psychiatry as
a means of triggering panic for diagnostic purposes and as
part of desensitization therapies for anxiety disorders.
1,2
The
procedure of voluntary hyperventilation has proven to be
safe after medical screening for contraindicating condi-
tions,
1–3
and has been demonstrated across numerous stud-
ies to be helpful in treatment of anxiety as a tool for diag-
nosis and desensitization.
1
Such uses for hyperventilation
are consequently now part of standard treatments for anxi-
ety disorders. Holotropic Breathwork (HB) is a novel, so-
matic, experiential psychotherapeutic procedure that in-
volves a number of diverse elements including music,
supportive touch, and elective bodywork (i.e., manually ex-
erted pressure aimed at releasing muscular tension or
spasm), and instructions to breathe “deeply and mindfully”
throughout the session.
3
Sessions typically last much longer
than talk-based psychotherapy sessions, usually ranging
from 1 to 3 hours, terminated voluntarily by the client. Most
elements of this treatment would appear to be best regarded
1
Private psychotherapy practice, Portland, OR.
2
Private holotropic breathwork practice, New York, NY.
as representing “common factors” of psychotherapy;
4
in-
deed, a competing hypothesis to ours would be that HB in-
volves nothing but a set of already-understood, placebo-like
elements that induce a nonspecific and mild therapeutic ef-
fect, much like that of a session of supportive psychother-
apy, massage, relaxation, or prayer. However, one element
of HB appears to be unique to this procedure, namely, that
of prolonged, deliberate overbreathing. This aspect of HB
would appear to capitalize upon the effects of hyperventila-
tion on the central nervous system to facilitate development
of a temporary, benign, and potentially therapeutic state of
altered consciousness. The purpose of this paper is to pose
the hypothesis that HB may a useful therapeutic modality
in treatment of psychiatric disorders. We will review phys-
iologic and psychologic effects of hyperventilation, along
with preliminary evidence suggesting efficacy of HB. We
will then pose a tentative, biopsychologic hypothesis of the
underlying mechanism of putative effects of HB, and offer
suggestions as to future studies examining this treatment.
NEUROPHYSIOLOGIC AND PSYCHOLOGIC
EFFECTS OF HYPERVENTILATION
Hyperventilation is known to produce a characteristic se-
ries of behavioral and physiological changes associated with
hypocapnia, a decrease in brain CO
2
partial pressure
(P
CO
2
)
5,6
and concomitant increase in pH known as respi-
ratory alkalosis, meaning excessive alkalinity of arterial
blood.
6
Typical symptoms associated with respiratory alka-
losis include dizziness, palpitations, and tingling/numbness
of the extremities.
5,7
These symptoms form the basis of ex-
posure procedures used in hyperventilation-enhanced treat-
ment of anxiety disorders,
1
because they are similar to so-
matic symptoms of anxiety. At the more extreme levels of
hypocapnia associated with prolonged hyperventilation, car-
popedal spasms, meaning involuntary contractions of the
muscles of the hands and feet, often emerge.
5
Such mani-
festations are known to be benign but are sometimes inter-
preted by the individual as signs of grave physical mal-
functioning, leading to panic and consequent escalation of
hyperventilation, the so-called “hyperventilation syn-
drome.”
8–11
Hypocapnia caused by hyperventilation has been demon-
strated to induce changes in a range of neurophysiologic
measures, including resting
12
and evoked
13,14
electroen-
cephalographic (EEG) as well as magnetoencephelographic
(MEG)
13,15
potentials, along with functional neuroimag-
ing
16
and cerebral hemodynamics.
17
Briefly, resting EEG in
hyperventilation has demonstrated slowing of brain activa-
tion rhythms across the brain, with substantial increases in
lower frequency,
- (up to 4 Hz) and
- (4–8 Hz) activity.
12
Visually evoked potentials have been shown to be altered
by voluntary hyperventilation, with increases in
-band
(30–45 Hz) responses to visual stimuli.
14
Long-latency
(100–200 millisecond) auditory and somatosensory evoked
potentials have been found to be suppressed after merely 3
minutes of voluntary hyperventilation;
13
similar reductions
were found in evoked responses measured by cerebral
MEG.
13
Direct-current MEG
15
has yielded evidence of an
increase in mean global cortex excitability during hyper-
ventilation.
15
Functional magnetic resonance imaging
(fMRI) has demonstrated rapid decreases of up to 10% in
MR signal within 20 seconds of initiation of hyperventila-
tion in areas of the frontal, occipital, and parietooccipital
cortex.
16
These changes are thought to reflect differences in
cerebral metabolic activity and/or vascular regulation in
these regions during hyperventilation.
16
Cerebral hemody-
namic measurement has shown that within 20–30 seconds
of voluntary hyperventilation, blood flow velocity decreases
in cerebral arteries, along with increases in capillary pH,
P
O
2
, and oxygen saturation.
17
Unsurprisingly, given the extent of the neurophysiologic
changes just summarized, hyperventilation also has been
shown to cause cognitive changes,
18
and when prolonged,
to induce subjectively altered consciousness that corre-
sponds temporally with the neurophysiologic changes.
19,20
Manifestations of altered consciousness emerging after ap-
proximately 8 minutes of hyperventilation have included
ringing/roaring in the ears, clouded vision, and feelings of
lightness, astonishment, and/or euphoria.
19
More dramatic
changes in consciousness, including perceptual distortions
and subjective “visions,” have been reported after periods
of hyperventilation exceeding 15 minutes.
19
With regard to
a whole-brain conceptual model, such phenomena may be
related to a “transient hypofrontality,”
21
meaning a brief pe-
riod of unusually low activity in the frontal cortex that has
been hypothesized to underlie a number of other altered
states of consciousness,
21
such as those found in half-asleep
states, meditation, exercise “highs,” and some drug-induced
states. It has been posited recently that there may be simi-
lar underlying neurobiologic changes associated with some
altered states of consciousness.
22
Our hypothesis is based in
part on the observation that prior research has found both
hypocapnia
14,23
and certain anesthetic agents such as keta-
mine
24–26
to alter oscillation patterns of
-range neuronal
activity (30–45 Hz), as will be discussed further herein.
PRELIMINARY EVIDENCE OF CLINICAL
UTILITY OF HOLOTROPIC BREATHWORK
Given the findings we have summarized thus far demon-
strating clear effects of hypocapnia on neurophysiologic
measures as well as subjective awareness, it would appear
plausible that the prolonged, voluntary hyperventilation in-
volved in HB might have some effect on symptoms of psy-
chiatric disorders. What is at issue is whether such effects
may be salutary, detrimental, or insignificant.
RHINEWINE AND WILLIAMS772
To date, few studies have examined empirically the ther-
apeutic potential of HB. Only three studies appear to meet
commonly accepted minimum criteria of methodological so-
phistication to be considered as constituting reliable empir-
ical evidence (that is, those showing clear aims and hy-
potheses, standardized procedures, objective, quantitative
measures with adequate and reported psychometric proper-
ties, some degree of control of potential confounds, and sta-
tistical analysis of results), and only one of these has been
published in a peer-reviewed journal.
27
Holmes and col-
leagues (1996)
27
compared HB with talk-based, experien-
tially oriented therapy (EOT). Participants were referred by
a pool of clinicians who practiced EOT (such as Gestalt ther-
apy). The authors examined two self-selected groups of 24
participants each, well-matched on demographic variables
and extent of prior psychotherapy treatment (mean 82.7
months for the HB group and 55.8 months for the psy-
chotherapy group); the HB group had experienced a mean
of 7.6 prior HB sessions compared with none for the ther-
apy-only group. Both groups were young to middle-aged
adults (mean 39.3 and 36.2 years, respectively), were pre-
dominantly female (19 of 24 for both groups), and all were
white. The HB group underwent six monthly HB sessions
as well as weekly EOT sessions. The psychotherapy-only
group received only the weekly EOT sessions, but were
given an additional assessment after six additional sessions
of psychotherapy as a control for the additional attention re-
ceived by the HB group.
Both groups were assessed at three timepoints, once be-
fore the 6-month treatment period, once at the end of 3
months, and once at the end of 6 months. Measures of clin-
ical improvement were selected based on the aspects of func-
tioning considered by the authors to be those most relevant
to experiential and existential therapies, including Templer’s
Death Anxiety Scale,
28
the Affiliation subscale of the Per-
sonality Research Form-E,
29
the Abasement scale from the
Personality Research Form-E
29
to measure self-esteem, and
an author-developed problems questionnaire that elicited the
top three problems for which participants were seeking treat-
ment, rated for severity on a Likert-type scale. The HB group
showed significantly greater changes over time on depen-
dent measures compared with the therapy-only group. Post-
hoc analyses demonstrated that the HB group showed greater
reductions in death anxiety on Templer’s Death Anxiety
Scale
28
and greater increases in self-esteem on the Person-
ality Research Form-E
29
compared with the therapy-only
group, controlling for number of prior psychotherapy ses-
sions. Analyses including the additional assessment for the
therapy-only group after six additional sessions yielded sim-
ilar results. Groups showed equal changes over time on the
problems questionnaire, suggesting that although HB plus
EOT was more helpful than EOT alone in the therapist-iden-
tified areas of death anxiety and self-esteem, HB augmen-
tation did not result in additional improvement in patient-
identified problem areas. The authors comment that this
controlled but nonrandomized trial provides some evidence
that nonverbal aspects of experientially oriented therapies
are important to efficacy, and that HB may be a useful ad-
junct to experientially oriented verbal psychotherapies, par-
ticularly for patients who have had many months of treat-
ment with inadequate clinical response.
Pressman* conducted a controlled study of 40 participants
matched for gender, ethnicity, and age, ranging widely on
these variables. Participants were recruited by advertisement
at a counseling center that conducts psychologic and spiri-
tual counseling services and workshops. The study examined
effects of HB on mood state (measured with the Profile of
Mood States
30
) and psychiatric symptomatology (measured
with the Brief Symptom Inventory
31
). Participants were as-
signed, based on matching, either HB or music therapy, with
the latter including the same music and postural components
of HB but omitting the voluntary hyperventilation and other
accompanying components of HB. The music therapy group
was offered debriefing as a substitute for the summary draw-
ing that customarily concludes HB sessions. Both groups un-
derwent one session of treatment every 2 weeks for a total
of six sessions, and were assessed before and after the course
of six sessions of treatment. Groups did not differ at base-
line on mood state or psychiatric symptoms. The author
found highly significant differences on all scales of the Pro-
file of Mood States
30
in the HB group compared to the mu-
sic group, signifying that a greater degree of altered con-
sciousness was induced in the HB group.* Furthermore,
although both groups were found to show improvements in
psychiatric symptomatology on the Brief Symptom Inven-
tory,
31
improvements were more consistent in the HB group,
suggesting that the HB group received greater psychologic
benefit from the six treatment sessions than did the music
therapy group. No patients showed undesirable changes from
pre- to post-treatment scores. This study thus offers modest,
preliminary evidence that HB may be more psychologically
beneficial than a common-factors
4
-based music therapy, and
also provides additional evidence that, at minimum, the pro-
cedure does not appear to be detrimental to individuals seek-
ing psychotherapy.
Hanratty,
†
in a one-group, repeated-measures, pre/post-
test designed study with a 6-month follow-up timepoint, ex-
amined 44 participants at an international HB workshop.
Study participants constituted 30% of the English-speaking
workshop attendees; their mean age was 48.7 years. Partic-
ipants were mostly (73%) female, and of a high educational
level (100% had had some college; 51.5% held a master’s
HOLOTROPIC BREATHWORK 773
*Pressman TE. The psychological and spiritual effects of
Stanislav Grof’s Holotropic Breathwork technique: An exploratory
study. San Francisco, CA: Saybrook Institute, 1993; unpublished
dissertation.
†
Hanratty PM. Predicting the outcome of Holotropic Breathwork
Using the High Risk Model of Threat Perception. San Francisco,
CA: Saybrook Institute, 2002; unpublished dissertation.
degree or higher). Dependent measures included the Telle-
gen Absorption Scale
32
and Marlowe-Crown Social Desir-
ability Scale
33
to measure aspects of participants’ personal-
ity, and the Positive and Negative Affect Schedule,
34
Templer’s Death Anxiety Scale,
28
and the Brief Symptom
Inventory
31
to measure aspects of psychiatric and psycho-
logic distress. Participants received two HB sessions of ap-
proximately 3–4 hours’ length over the course of 1 week.
At post-test, participants were found to show significant re-
ductions in negative affect as measured by the Positive and
Negative Affect Scale,
34
and significant reductions of psy-
chiatric symptoms on the Brief Symptom Inventory.
31
At 6-
month follow-up (N 22), mailed questionnaires indicated
that reductions in overall psychiatric symptoms were main-
tained, although reductions in Negative Affectivity were no
longer significant, and Positive Affectivity actually dropped
significantly. The author speculates that the latter result may
be attributed to a global reduction in arousal induced by HB.
Participants were found to have elevated scores compared
to established norms on the Positive Symptom total of the
Brief Symptom Inventory
31
at all timepoints, suggesting that
they represented, at minimum, a mildly psychiatrically dis-
tressed population. Interestingly, participants were also
found to score higher on the Tellegen Absorption Scale
32
and Marlowe-Crown Social Desirability Scale
33
than the
norm for the general population, indicating that participants
in this study were unusually high in trait absorption and so-
cial desirability. The author suggests that high trait absorp-
tion and social desirability may predict positive response to
HB. This study represents further preliminary evidence that
HB may be psychologically beneficial, and specifically that
it may reduce psychiatric symptoms in mild-to-moderately
distressed, educated, white females.
HYPOTHESIZED MECHANISM OF ACTION
OF HOLOTROPIC BREATHWORK
We have developed a tentative, biopsychologic hypothe-
sis of putative psychotherapeutic effects of HB, drawing on
laboratory findings in humans and animals concerning
hypocapnia, which we will describe now as follows. We be-
lieve that the altered consciousness induced by prolonged,
voluntary hyperventilation as well as the “set and setting”
elements of HB involve a process of exposure to feared, in-
ternal, affective stimuli in the context of a supportive ther-
apeutic setting, with resulting extinction of covert avoidance
behaviors. This process of relatively sudden behavioral
change is subjectively experienced by patients as “cathar-
sis.” Individuals who are considered to be suffering from re-
fractory anxiety or depressive disorders, and/or those who
may be conceptualized by their therapists as posing strong
“resistance” to treatment, often experience fresh progress in
psychotherapy after such experiences, with concomitant re-
duction in objective psychiatric symptoms. Such experi-
ences are best conceptualized behaviorally as representing
generalized extinction of internal, covert, avoidance behav-
iors on the part of the patient. A similar process has been
demonstrated recently using the N-methyl-
D
-aspartate
(NMDA) receptor agonist
D
-cycloserine administered
acutely after exposure treatment for anxiety disorders.
35
The NMDA antagonist ketamine has been implicated as
a potential antidepressant agent
36–39
as well as a potentially
useful adjunct to treatment of substance abuse disorders.
40
Studies using anesthetic agents in rat hippocampal tissue
samples
24–26
have demonstrated that such agents disrupt
-range (30–45 Hz) oscillations thought to serve a “bind-
ing” or associative function among distant populations of
neurons, which may account for the dissociative effects of
these drugs upon conscious awareness. Gamma activity oc-
curs throughout the human brain in areas understood to be
important to the state of subjective awareness, including the
neocortex, hippocampus, and thalamus,
24
and appears to
play a role in temporal modulation (i.e., timing control of
action-potential generation across populations of neurons).
24
Although unproven at this time, the neuronal binding func-
tion of
oscillation has been hypothesized to help maintain
a normal state of consciousness in which activity across dis-
parate brain areas occurs in tandem, “associated” rather than
dissociated.
24–26
If supported by future research evidence,
such a model would show that neuronal dissociation under-
lies psychologic dissociation. Similar disruptive effects on
oscillations were found for anesthetic agents with diverse
pharmacodynamics but similar effects on consciousness, in-
cluding those that act on -amino-butyric acid (in the cases
of thiopental, propofol, and morphine)
25
as well as NMDA
receptors (ketamine).
25
Under hypocapnic conditions, rat hippocampal tissue
samples also have shown significant alteration in patterns of
gamma oscillations.
23
Like ketamine and other anesthetic
agents,
25
the prolonged, voluntary hyperventilation involved
in HB may exert its primary action on consciousness via al-
tering the temporal stability of gamma activity in key brain
areas, consistent with effects on visually evoked
responses
found during voluntary hyperventilation.
14
Voluntary hy-
perventilation has been found to be associated with tem-
porarily reduced MR signal in the frontal cortex that resolves
quickly upon cessation of hyperventilation.
16
Disruption of
stability of
activity has been hypothesized to represent a
neurophysiologic correlate of psychologic dissociation.
24–26
Under conditions of psychologic dissociation, one would ex-
pect alterations in normal patterns of regional cortical acti-
vation, particularly in the frontal lobes.
21
Indeed, transient
hypofrontality has been theorized to underlie a range of al-
tered states of consciousness,
21
all of which involve a de-
gree of psychologic dissociation. Given that the frontal lobes
are involved in control and selective inhibition of cognition
and behavior, both hypocapnia and low-dose anesthetics
may cause a temporary weakening of the inhibitory action
RHINEWINE AND WILLIAMS774
of the frontal lobes upon cognition and related subjective
experience, resulting in disinhibition of previously avoided
or “suppressed” internal stimuli.
21,41
Thus, dissociation and
disinhibition may facilitate experiential exposure to feared
internal representations. In the context of the supportive
therapeutic conditions of HB, including several “common-
factors” elements of psychotherapy as described herein, such
exposure may result in extinction of the covert avoidance
behaviors and thereupon, resolution of the consequent be-
havioral “resistance” that characterizes difficult-to-treat psy-
chiatric disorders. Such an account would explain the pre-
liminary results suggesting usefulness of HB specifically
among individuals who have had many months of psycho-
therapy with inadequate clinical progress.
27
Alternatively, it
is also possible that HB exerts psychotherapeutic effects via
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 found
to occur several days after full return to normal conscious-
ness.
36–38
FUTURE RESEARCH DIRECTIONS
AND CONCLUSIONS
We have argued that HB may exert its primary psy-
chotherapeutic effects via a combination of psychologic
mechanisms along with a hypothesized biopsychologic set
of mechanisms we have described herein. We wish to sug-
gest several potential future lines of research to test our hy-
potheses. First, a controlled study of HB using an adequate
sample size and representing a diagnostically homogeneous
clinical population as evaluated by standardized interviews
would be needed in order to determine definitively whether
HB should be considered a useful complementary or alter-
native treatment for common psychiatric disorders. Use of
multiple, commonly used outcome measures with well-es-
tablished psychometric properties, as well as inclusion of a
placebo or wait-list control condition, with random assign-
ment of participants to groups, would greatly enhance the
interpretability of findings. Furthermore, it would be useful
to explore which traits may predict response to HB, because
traits such as social desirability and hypnotizibility have
been implicated in a prior, unpublished study.
†
Mechanism
of action of HB may be explored via psychophysiologic
measurements concurrent with a clinical trial. Advanced
neuroimaging techniques such as fMRI may be utilized fur-
ther to provide more specific localization of brain activity
changes during HB. To tease apart psychologic versus di-
rect physiologic effects of hypocapnia, future studies may
examine whether mere prolonged overbreathing, without
other aspects of HB in place, would exert a similar treat-
ment-augmentation effect. It is our view, however, that al-
though hypocapnia may be the ingredient that sets HB apart
from purely common-factors-based
4
interventions, hypocap-
nia alone is not likely to exert the same psychotherapeutic
effects as HB.
ACKNOWLEDGMENTS
This project was made possible in part by private fund-
ing administered by the John E. Mack Institute. The authors
would like to thank the following individuals for reading
and providing comments on early drafts of the manuscript:
Cindy Smith, M.D., Jon Emens, M.D., Pradeep Nagachan-
dran, M.D., Timothy Catlow, Psy.D., and Kristin Flegal,
B.A.
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