Physiology of long pranayamic breathing: Neural respiratory elements may provide a mechanism that explains how slow deep breathing shifts the autonomic nervous system

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DOI: 10.1016/j.mehy.2006.02.042 · Source: PubMed
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Abstract
Pranayamic breathing, defined as a manipulation of breath movement, has been shown to contribute to a physiologic response characterized by the presence of decreased oxygen consumption, decreased heart rate, and decreased blood pressure, as well as increased theta wave amplitude in EEG recordings, increased parasympathetic activity accompanied by the experience of alertness and reinvigoration. The mechanism of how pranayamic breathing interacts with the nervous system affecting metabolism and autonomic functions remains to be clearly understood. It is our hypothesis that voluntary slow deep breathing functionally resets the autonomic nervous system through stretch-induced inhibitory signals and hyperpolarization currents propagated through both neural and non-neural tissue which synchronizes neural elements in the heart, lungs, limbic system and cortex. During inspiration, stretching of lung tissue produces inhibitory signals by action of slowly adapting stretch receptors (SARs) and hyperpolarization current by action of fibroblasts. Both inhibitory impulses and hyperpolarization current are known to synchronize neural elements leading to the modulation of the nervous system and decreased metabolic activity indicative of the parasympathetic state. In this paper we propose pranayama's physiologic mechanism through a cellular and systems level perspective, involving both neural and non-neural elements. This theoretical description describes a common physiological mechanism underlying pranayama and elucidate the role of the respiratory and cardiovascular system on modulating the autonomic nervous system. Along with facilitating the design of clinical breathing techniques for the treatment of autonomic nervous system and other disorders, this model will also validate pranayama as a topic requiring more research.
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Physiology of long pranayamic breathing: Neural
respiratory elements may provide a mechanism
that explains how slow deep breathing shifts the
autonomic nervous system
Ravinder Jerath *, John W. Edry, Vernon A. Barnes, Vandna Jerath
Augusta Women’s Center, 2100 Central Avenue, Suite 6 & 7, Augusta, GA 30904, United States
Received 20 January 2006; accepted 23 February 2006
Summary Pranayamic breathing, defined as a manipulation of breath movement, has been shown to contribute to a
physiologic response characterized by the presence of decreased oxygen consumption, decreased heart rate, and
decreased blood pressure, as well as increased theta wave amplitude in EEG recordings, increased parasympathetic
activity accompanied by the experience of alertness and reinvigoration. The mechanism of how pranayamic breathing
interacts with the nervous system affecting metabolism and autonomic functions remains to be clearly understood. It is
our hypothesis that voluntary slow deep breathing functionally resets the autonomic nervous system through stretch-
induced inhibitory signals and hyperpolarization currents propagated through both neural and non-neural tissue which
synchronizes neural elements in the heart, lungs, limbic system and cortex. During inspiration, stretching of lung tissue
produces inhibitory signals by action of slowly adapting stretch receptors (SARs) and hyperpolarization current by
action of fibroblasts. Both inhibitory impulses and hyperpolarization current are known to synchronize neural elements
leading to the modulation of the nervous system and decreased metabolic activity indicative of the parasympathetic
state. In this paper we propose pranayama’s physiologic mechanism through a cellular and systems level perspective,
involving both neural and non-neural elements. This theoretical description describes a common physiological
mechanism underlying pranayama and elucidate the role of the respiratory and cardiovascular system on modulating
the autonomic nervous system. Along with facilitating the design of clinical breathing techniques for the treatment of
autonomic nervous system and other disorders, this model will also validate pranayama as a topic requiring more
research.
c2006 Published by Elsevier Ltd.
Introduction
Pranayama: a brief review
‘‘Pranayama’’ (the practice of voluntary breath
control, consisting of conscious inhalation, reten-
0306-9877/$ - see front matter
c2006 Published by Elsevier Ltd.
doi:10.1016/j.mehy.2006.02.042
*Corresponding author. Tel.: +1 706 736 5378; fax: +1 706 738
9922.
E-mail address: RJ605R@aol.com (R. Jerath).
Medical Hypotheses (2006) x, xxx–xxx
http://intl.elsevierhealth.com/journals/mehy
ARTICLE IN PRESS
tion and exhalation) is often practiced in conjunc-
tion with ‘‘dhyana’’ (meditation), and ‘‘asanas’’
(physical posture) [1]. Versions of pranayama vary
from single nostril breathing to belly breathing.
Pranayama consists of three phases: ‘‘puraka’’
(inhalation); ‘‘kumbhaka’’ (retention) and ‘‘rec-
haka’’ (exhalation) that can be either fast or slow
[2]. Although all pranayama has three phases, dif-
ferent forms of pranayama evoke dissimilar and
sometimes opposite responses in the subject
depending on variables such as which nostril is used
or the speed of the respiration. Pranayama has
been researched mostly for its beneficial applica-
tions in treatment of cardiovascular diseases such
as hypertension [2–4], pulmonary disease such as
asthma [5–7], autonomic nervous system imbal-
ances [8], and psychologic or stress related disor-
ders [4,9].
Pranayama is known to improve pulmonary func-
tion [10] and cardiovascular profile [2–4]. A But-
eyko breathing device, which mimics pranayama,
was shown to improve symptoms and reduce bron-
chodilator use in asthma patients [5,7]. Pranayama
has also been shown, over time, to reduce oxygen
consumption per unit work [11]. ‘‘Kapalabhati’’,
a fast breathing pranayamic technique, has been
shown to promote decarboxylation and oxidation
mechanisms in the lungs which is believed to
‘‘quiet’’ the respiratory centers [12]. Alteration
in information processing at the primary thalamo-
cortical level inducing modification in neural mech-
anisms regulating the respiratory system [13] may
contribute to pranayama’s beneficial pulmonary
effects. In studies that examined pranayama as a
form of exercise, nostril breathing was shown to in-
crease hand grip strength of both hands [14]. Pra-
nayama, by reducing risk factors associated with
cardiovascular disease [15], has shown that it is
not only theraputic but also preventative. Reduc-
tion in oxidative stress levels with increased super-
oxide dismutase and decreased number of free
radicals may explain in part the beneficial long-
term impact pranayama has on the cardiopulmo-
nary system [16].
Pranayama is known to increase neural plasticity
and to alter information processing making it a pos-
sible treatment for psychological and stress disor-
ders or improving one’s psychological profile
[4,9]. Higher improvement in IQ and social adapta-
tion parameters were noticed in mentally retarded
children after yogic training including pranayama
[17]. Sudarshan Kriya Yoga, which includes pranay-
ama, has been used as a public health intervention
for treatment of post traumatic stress disorder,
depression, stress related medical illnesses, sub-
stance abuse, and rehabilitation of criminal
offenders for its ability to enhance well being,
mood, attention, mental focus, and stress toler-
ance [9]. In conjunction with other yogic tech-
niques, pranayama has been shown to decrease
symptoms of irritable bowel syndrome by enhanc-
ing parasympathetic activity of gastrointestinal
tract and by reducing effects of stress [18]. It has
been mentioned as a possible treatment for symp-
toms of epilepsy [1] and has been shown to in-
crease plasticity of motor control indicating that
it might have applications in rehabilitation pro-
grams [19].
Different forms of pranayama activate different
branches of the autonomic nervous system effect-
ing oxygen consumption, metabolism and skin
resistance. Pranayamic breathing, characterized
by brief breath retention, caused significant in-
creases in oxygen consumption and metabolic rate
while pranayamic breathing, characterized by long
breath retention, caused lowering of oxygen
consumption and metabolic rate [20]. This demon-
strates that slow breathing enhances parasympa-
thetic activation. In another study using breathing
exercises mimicking pranayama, slow breathing
over a period of three months was shown to im-
prove autonomic function while fast breathing did
not have an effect on the autonomic nervous sys-
tem [8]. Slow breathing pranayamic exercises show
a strong tendency of improving or balancing the
autonomic nervous system through enhanced acti-
vation of parasympathetic nervous system. In con-
trast to slow pranayamic breathing, nostril
breathing, both through right nostril, left nostril,
and both nostrils, has been shown to increase base-
line oxygen consumption indicative of sympathetic
discharge of the adrenal medulla [21]. Contradicto-
rily, left nostril breathing has been shown to in-
crease volar galvanic skin resistance interpreted
as a reduction in sympathetic nervous activity
[21]. Although nostril breathing and short pranaya-
mic breathing practices are capable of altering the
autonomic nervous system, more research is re-
quired to fully understand their clinical benefits
[21].
Pranayama may also affect the immune system.
Inhibition of the sympathetic nervous system has
been shown to enhance function of the immune
system in several forms of meditation including
mindfulness meditation, Qigong, and Transcenden-
tal meditation [22–25]. Since pranayama has been
shown to shift the autonomic nervous system away
from sympathetic dominance [8,26] it is probable
that pranayama may have beneficial immune ef-
fects similar to meditation. More studies are
needed to elucidate pranayama’s direct effect on
immune function.
2 Jerath et al.
ARTICLE IN PRESS
Although many studies show pranayama is a ben-
eficial technique, there have been studies that
indicate possible risks especially associated with
fast breathing versions. If done improperly, fast
breathing pranayama can cause hyperventilation
and may hyperactivate the sympathetic nervous
system [27] which may stress the body. Pneumo-
thorax has been attributed to fast breathing
‘‘Kapabhati’’ pranayama in one case study [28].
Some studies indicate that deep breathing similar
to slow breathing pranayama may agitate symp-
toms of bronchial hyperactivity. Deep breathing in-
duced parasympathetic activity is correlated with
bronchial hyperactivity in asthmatics [29]. It is pos-
sible that pranayamic parasympathetic activity
may elicit bronchial hyperactivity in asthmatics as
well.
Pranayamic breathing has been shown to be a
beneficial clinical application in the treatment
of psychological disorders as well as physiological
diseases. Research has revealed pranayamic
breathing to be a low risk, cost effective adjunct
treatment that can be potentially applied to im-
prove symptoms associated with cardiovascular
disorders, autonomic disorders, and psychological
disorders including those involving stress [9].
Although slow pranayamic breathing is said to
be one of the most practical relaxation tech-
niques [2] and holds a great deal of potential in
the treatment of autonomic and psychological
disorders, two problems exist in present research
that prevent full application and understanding of
this practice. The first is that there is no coher-
ent model for the mechanism underlying slow
pranayamic breathing. A physiological description
of the pranayamic mechanism would provide in-
sight into the cellular physiology of deep breath-
ing and the dynamic connection between the
nervous system and respiration. Secondly, many
studies report only the effects of pranayama, yo-
gic postures, and meditation collectively. In fu-
ture research, pranayama needs to be studied
exclusively without meditation or postures in or-
der to fully understand the pranayamic mecha-
nism. Within the research conducted on the
many different types of pranayama, slow rhyth-
mic pranayamic breathing seems to be the most
practical and hold the most physiological benefit.
Slow pranayama, a treatment for autonomic
disorders
Slow pranayamic breathing, characterized as regu-
lar slow frequency respiration with long periods of
breath retention has been known to cause short-
term and long-term changes in physiology. One
long-term effect of pranayamic breathing is the
improvement in autonomic function [3]; specifi-
cally, with slow breathing pranayama there is a
noted increase in parasympathetic activity and a
decrease in sympathetic dominance [8]. It has been
suggested that the cardio-respiratory system can
be normalized through rhythmic breathing exer-
cises [30,31] such as slow pranayama.
Short-term effects of slow pranayamic breathing
include increased galvanic skin resistance (a non-
neural response) [21], decreased oxygen consump-
tion [20], decreased heart rate, decreased blood
pressure [3], and increased amplitude of theta
waves [32]. Increase theta amplitude and delta
waves during breath retention and slow breathing
is indicative of a parasympathetic state while alpha
and beta waves signify activity. Both the short-
term and long-term effects of pranayamic breath-
ing indicate a dynamic alteration of the autonomic
system.
There are several chemical and non-chemical
mechanisms that may account for some of the
physiologic phenomena experienced by pranayama
practitioners. No significant changes in arterial
blood gases were noted after pranayama practice
indicating a neural mechanism for pranayama’s ef-
fect [33]. Increased melatonin production after a
regimen of slow breathing pranayamic exercises
has been attributed to pranayama’s tendency to
create a sense of relaxation and well being in the
subject [4]. Breath holding, an essential part of
pranayama, is shown to induce theta waves [32].
A decrease in breathing frequency can increase
synchronization of brain waves eliciting delta wave
activity [34] indicating parasympathetic domi-
nance. Although these mechanisms provide some
clues to pranayama’s mechanism, the neural mech-
anism that causes this body-wide autonomic shift is
largely unknown [3]. It has been proposed that cer-
tain voluntary breathing exercises can modulate
the parasympathetic and sympathetic nervous sys-
tem bringing their levels of activation into a normal
range [35]. Some have proposed that pranayama al-
ters autonomic responses to breath holding per-
haps by increasing vagal tone and decreasing
sympathetic discharges [26]. It has been suggested
that pranayama ‘‘balances’’ the autonomic ner-
vous system through stretch-induced inhibitory sig-
nals of abdominal muscles (specifically the
diaphragm) and even nerve endings in the nose
[32]. It is abundantly evident that respiration and
the parasympathetic response are intricately con-
nected. What is not clear, however, is the cellular
mechanism that integrates respiration and the
parasympathetic response.
Physiology of long pranayamic breathing 3
ARTICLE IN PRESS
Hypothesis
The general cellular mechanism of
pranayama
It is our hypothesis that voluntary, slow, deep
breathing functionally resets the autonomic ner-
vous system through stretch-induced inhibitory sig-
nals and hyperpolarization currents propagated
through both neural and non-neural tissue which
synchronizes neural elements in the heart, lungs,
limbic system, and cortex.
It is suspected that deep pranayamic breathing,
by voluntary control, dynamically modulates the
autonomic nervous system by heightening genera-
tion of two physiologic signals: (1) Pranayama
increases frequency and duration of inhibitory
neural impulses by activating stretch receptors
of the lungs during above tidal volume inhalation
(as seen in the Hering Breuer’s reflex). (2) Pranay-
ama heightens generation of hyperpolarization cur-
rent by stretch of connective tissue (fibroblasts)
localized around the lungs (see Fig. 1). It is recog-
nized that inhibitory impulses, produced by slowly
adapting receptors (SARs) in the lungs during infla-
tion [36], play a role in controlling typically auto-
nomic functions such as breathing pattern, airway
smooth muscle tone, systemic vascular resistance,
and heart rate [37]. Stretch of connective tissue
fibroblasts are capable of effecting the membrane
potential of nervous tissue [38]. Both hyperpo-
larization and inhibitory impulses generated by
stretch of neural and non-neural tissue of the lungs
are the likely agents of autonomic shift during pra-
nayamic breathing.
Inhibitory current synchronizes rhythmic cellular
activity between the cardiopulmonary center [39]
and the central nervous system [40]. Inhibitory cur-
rent regulates excitability of nervous tissues [41]
and is known to elicit synchronization of neural ele-
ments which typically is indicative of a state of
relaxation [42]. Synchronization within the hypo-
thalamus and the brainstem [43] is likely responsi-
ble for inducing the parasympathetic response
[44] during breathing exercises. The strongest car-
dioventilatory coupling, a parasympathetic-type
phenomenon, occurs when there is decreased
Slow pranayamic
breathing
Generation of
inhibitory impulses in
neural tissue
Generation of
hyperpolarization
current
Inhibitory impulses
in neural tissue
synchronize tissue
Synchronization of
neural tissue
includ ing
hypothalamus and
brainste
m
Decreased action
potentials in
neural tissue
Increased
Par asympath etic
dominance
Activation of slowly adapting
stretch receptors (SARs)
Decreased BP,
heart rate, O2
consumption
Stretch of fibroblasts
surrounding lungs
Resting membrane
potential polarity
increases in
surrounding tissue
decreasing metabolic
act ivit
y
Figure 1 Diagram of the series of events that occur during the autonomic shift present in pranayamic slow breathing.
4 Jerath et al.
ARTICLE IN PRESS
breathing frequency [45] similar to that found in
slow pranayama. Cardioventilatory coupling, found
during deep breathing exercises, indicates a syn-
chronization mechanism that coordinates neural
and non-neural activity. It is likely that inhibitory
synchronized activity between the lungs and brain
elicits parasympathetic-like states.
Hyperpolarization affects the autonomic ner-
vous system by modulating neuronal excitability
[46], resting membrane potential [39], and gener-
ating rhythmic brain activity [40]. It is well docu-
mented that hyperpolarization of tissues
manifests itself in parasympathetic-like changes
[47]. Hyperpolarization is generated during stretch
of fibroblasts in tissue surrounding the lungs [38].
Similarly, in some neurons, hyperpolarization cur-
rent inhibits unsynchronized neuronal input [46]
thereby increasing the dominance of synchronized
input. Stretch of lung fibroblasts likely contributes
to the generation of the slower wave brain activity
and the parasympathetic autonomic shift present
during slow pranayamic breathing exercises.
There are several ways to test the hypothesis
that voluntary slow pranayama functionally resets
the autonomic nervous system through stretch-
induced inhibitory signals and hyperpolarization
currents propagated through both neural and non-
neural tissue. Simultaneous, intracellular, in vivo
recordings of fibroblasts and endothelium in the
lungs and heart during slow pranayamic breathing
would show that hyperpolarizing currents, originat-
ing in the lungs, are being propagated long dis-
tances affecting the cellular metabolism as well
as nervous system excitability. Blockade of inhibi-
tory signals during activation of lung stretch recep-
tors would likely show a decrease in the
parasympathetic effect of slow pranayamic breath-
ing consistent with our model. A recording measur-
ing autonomic indicators such as respiratory sinus
arrhythmia (RSA), the frequency of heart rate var-
iability, and EEG during the practice of pranayama
would also suggest that this deep breathing tech-
nique resets the autonomic nervous system through
parasympathetic shift and causes increased syn-
chronization of neural elements with the heart,
lungs, and cortex.
This hypothesis presents a common physiological
mechanism underlying several forms of breathing
exercises and elucidates the role of the respiratory
and cardiovascular system on modulating the auto-
nomic nervous system. Revealing the cellular
mechanisms that shifts the autonomic nervous sys-
tem towards parasympathetic dominance is impor-
tant for the general understanding of yogic
breathing practices and breathing physiology. The
cooperative action of pulmonary slowly adapting
stretch receptors, heart and lung fibroblasts, vas-
cular endothelium, nervous system glia and neu-
rons during voluntary deep breathing needs to be
further investigated at the cellular level.
Conclusion
Slow pranayamic breathing generates inhibitory
signals and hyperpolarizing current within neural
and non-neural tissue by mechanically stretching
tissues during breath inhalation and retention. It
is likely that inhibitory impulses in cooperation
with hyperpolarization current initiates the syn-
chronization of neural elements in the central ner-
vous system, peripheral nervous system, and
surrounding tissues ultimately causing shifts in
the autonomic balance towards parasympathetic
dominance. Further experimental research of the
cooperative cellular mechanisms of pranayama is
needed to confirm this theory.
References
[1] Yardi N. Yoga for control of epilepsy. Seizure 2001;10(1):
7–12.
[2] Chodzinski J. The effect of rhythmic breathing on blood
pressure in hypertensive adults. J Undergrad Res 2000;1(6).
[3] Singh S et al. Role of yoga in modifying certain cardiovas-
cular functions in type 2 diabetic patients. J Assoc
Physician India 2004;52:203–6.
[4] Harinath K et al. Effects of Hatha yoga and Omkar
meditation on cardiorespiratory performance, psychologic
profile, and melatonin secretion. J Altern Complement Med
2004;10(2):261–8.
[5] Cooper S et al. Effect of two breathing exercises (Buteyko
and pranayama) in asthma: a randomised controlled trial.
Thorax 2003;58(8):674–9.
[6] Singh V, Chowdhary R, Chowdhary N. The role of cough and
hyperventilation in perpetuating airway inflammation in
asthma. J Assoc Physician India 2000;48(3):343–5.
[7] Vedanthan P et al. Clinical study of yoga techniques in
university students with asthma: a controlled study. Allergy
Asthma Proc 1998;19(1):3–9.
[8] Pal G, Velkumary S, Madanmohan. Effect of short-term
practice of breathing exercises on autonomic functions in
normal human volunteers. Indian J Med Res 2004;120(2):
115–21.
[9] Brown R, Gerbarg P. Sudarshan Kriya Yogic breathing in the
treatment of stress, anxiety, and depression: part II–
clinical applications and guidelines. J Altern Complement
Med 2005;11(4):711–7.
[10] Malhotra V et al. Study of yoga asanas in assessment of
pulmonary function in NIDDM patients. Indian J Physiol
Pharmacol 2002;46(3):313–20.
[11] Raju PS et al. Comparison of effects of yoga & physical
exercise in athletes. Indian J Med Res 1994(100):81–6.
[12] Desai B, Gharote M. Effect of Kapalabhati on blood urea,
creatinine and tyrosine. Act Nerv Super (Praha) 1990;32(2):
95–8.
Physiology of long pranayamic breathing 5
ARTICLE IN PRESS
[13] Telles S et al. Alterations of auditory middle latency
evoked potentials during yogic consciously regulated
breathing and attentive state of mind. Int J Psychophysiol
1993;14(3):189–98.
[14] Raghuraj P et al. Pranayama increases grip strength with-
out lateralized effects. Indian J Physiol Pharmacol
1997;41(2):129–33.
[15] Bijlani R et al. A brief but comprehensive lifestyle educa-
tion program based on yoga reduces risk factors for
cardiovascular disease and diabetes mellitus. J Altern
Complement Med 2005;11(2):267–74.
[16] Bhattacharya S, Pandey U, Verma N. Improvement in
oxidative status with yogic breathing in young healthy
males. Indian J Physiol Pharmacol 2002;46(3):349–54.
[17] Uma K et al. The integrated approach of yoga: a thera-
peutic tool for mentally retarded children: a one-year
controlled study. J Ment Defic Res 1989;33(5):415–21.
[18] Taneja I et al. Yogic versus conventional treatment in
diarrhea-predominant irritable bowel syndrome: a random-
ized control study. Appl Psychophysiol Biofeedback
2004;29(1):19–33.
[19] Telles S et al. Plasticity of motor control systems demon-
strated by yoga training. Indian J Physiol Pharmacol
1994;38(2):143–4.
[20] Telles S, Desiraju T. Oxygen consumption during pranaya-
mic type of very slow-rate breathing. Indian J Med Res
1991;94:357–63.
[21] Telles S. Breathing through a particular nostril can alter
metabolism and autonomic activities. Indian J Physiol
Pharmacol 1994;38(2):133–7.
[22] Collins M, Dunn L. The effects of meditation and visual
imagery on an immune system disorder: dermatomyositis. J
Altern Complement Med 2005;11(2):275–84.
[23] Davidson R et al. Alterations in brain and immune function
produced by mindfulness meditation. Psychosom Med
2003;65(4):564–70.
[24] Lee M et al. Effects of Qigong on immune cells. Am J Chin
Med 2003;31(2):327–35.
[25] Takahashi T et al. Changes in EEG and autonomic nervous
activity during meditation and their association with
personality traits. Int J Psychophysiol 2005;55(2):199–207.
[26] Bhargava R, Gogate M, Mascarenhas J. Autonomic
responses to breath holding and its variations following
pranayama. Indian J Physiol Pharmacol 1988;32(4):257–64.
[27] Telles S, Nagarathna R, Nagendra H. Physiological measures
of right nostril breathing. J Altern Complement Med
1996;2(4):479–84.
[28] Johnson D, Tierney M, Sadighi P. Kapalabhati pranayama:
breath of fire or cause of pneumothorax? a case report.
Chest 2004;125(5):1951–2.
[29] Kallenbach J et al. Reflex heart rate control in asthma.
Evidence of parasympathetic overactivity. Chest 1985;87(5):
644–8.
[30] Gopal K et al. The cardiorespiratory adjustments in ‘pra-
nayama’, with and without ‘bandhas’, in ‘vajrasana’.
Indian J Med Sci 1973;27(9):686–92.
[31] Iyengar BKS. Light on pranayama: the yogic art of breath-
ing. New York: Crossroad; 1998.
[32] Austin JH. Zen and the brain. Cambridge (MA): MIT Press;
1998.
[33] Pratap V, Berrettini W, Smith C. Arterial blood gases
in pranayama practice. Percept Mot Skill 1978;46(1):
171–4.
[34] Busek P, Kemlink D. The influence of the respiratory cycle
on the EEG. Physiol Res 2005;54:327–33.
[35] Sydorchuk L, Tryniak M. Effect of voluntary regulation of
the respiration on the functional state of the autonomic
nervous system. Lik Sprava 2005(1–2):65–8.
[36] Matsumoto S et al. Inhibitory mechanism of slowly adapt-
ing pulmonary stretch receptors after release from hyper-
inflation in anesthetized rabbits. Life Sci 2000;67(12):
1423–33.
[37] Schelegle E, GreenSchelegle J. An overview of the anatomy
and physiology of slowly adapting pulmonary stretch
receptors. Respir Physiol 2001;125(1–2):17–31.
[38] Kamkin A et al. Electrical interaction of mechanosensitive
fibroblasts and myocytes in the heart. Basic Res Cardiol
2005;100(4):337–45.
[39] Siegelbaum R, Robinson S. Hyperpolarization activated
cation current: from molecules to physiological function.
Annu Rev Physiol 2003:65.
[40] Roberts L, Greene J. Hyperpolarization – activated current
(Ih): a characterization of subicular neurons in brain slices
from socially and individually housed rats. Brain Res
2005;1040(1–2):1–13.
[41] Cuttle MF et al. Modulation of a presynaptic hyperpolar-
ization – activated cationic current (Ih) at an excitatory
synaptic terminal in the rat auditory brainstem. J Physiol
2001;534(3):733–44.
[42] Westbrook GL. In: Kandel ER, Schwartz JH, Jessell TM,
editors. Principles of neuroscience. New York: McGraw-
Hill; 2000.
[43] Newberg A, Iversen J. The neural basis of the complex
mental task of meditation: neurotransmitter and neuro-
chemical considerations. Med Hypotheses 2003;61(2):
282–91.
[44] Lutz A et al. Long-term meditators self-induce high-
amplitude gamma synchrony during mental practice. Proc
Natl Acad Sci USA 2004;101(46):16369–73.
[45] Tzeng Y, Larsen P, Galletly D. Cardioventilatory coupling in
resting human subjects. Exp Physiol 2003;88(6):775–82.
[46] Migliore M, Messineo L, Ferrante M. Dendritic Ih selectively
blocks temporal summation of unsynchronized sistal inputs in
CA1 pyramidal neurons. J Comput Neurosci 2004;16(1):5–13.
[47] Benson H. The relaxation response: the therapeutic effect.
Psychiatry 1974;37:1694–5.
6 Jerath et al.
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  • ... [42] Slow pranayamic breathing generates inhibitory signals and hyperpolarizing current within neural and nonneural tissue by mechanically stretching tissues during breath inhalation and retention. [43] It is likely that these inhibitory impulses in cooperation with hyperpolarization current initiate the synchronization of neural elements in the central nervous system, peripheral nervous system, and surrounding tissues ultimately causing shifts in the autonomic balance toward parasympathetic dominance. [43] This shift toward parasympathetic dominance is likely to be responsible for the observed cardiovascular effects of Pranayama practice, such as reduced heart rate, SBP, and DBP in patients with hypertension. ...
    ... [43] It is likely that these inhibitory impulses in cooperation with hyperpolarization current initiate the synchronization of neural elements in the central nervous system, peripheral nervous system, and surrounding tissues ultimately causing shifts in the autonomic balance toward parasympathetic dominance. [43] This shift toward parasympathetic dominance is likely to be responsible for the observed cardiovascular effects of Pranayama practice, such as reduced heart rate, SBP, and DBP in patients with hypertension. ...
    ... [44] Breath-holding, an essential part of pranayama, is known to induce theta waves in the electroencephalography. [43] The particular contribution of pranayama to stress/anxiety reduction might also be contributed by the sympathetic-parasympathetic shift. Vagal afferents from peripheral receptors are connected with the nucleus tractus solitarius from which fibers ascend to the thalamus, limbic areas, and anterior cortical areas. ...
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    Background: Pranayama (yogic breathing) has demonstrated numerous beneficial health effects. At present, there are no systematic reviews evaluating the beneficial health effects of pranayama alone as a practice. Aim: The aim of this study is to perform a systematic review about the beneficial health effects of pranayama. Methods: Data were obtained using a stepwise search process by searching the online PubMed, Web of Science, and SciVerse Scopus databases using keywords. Controlled clinical trials in humans, using "Pranayama" as an intervention with an appropriate control group and evaluating health-related outcomes were selected for inclusion. Results: Initial database searching indicated 669 potentially eligible articles, of which 18 studies satisfying the inclusion/exclusion criteria were selected. All were controlled trials, of which 13 were randomized and 1 was a crossover study. Number of participants ranged from 16 to 160, and the duration of pranayama practice varied from 4 days to 6 months. Studies demonstrated a significant effect on cardiorespiratory functions, in patients with bronchial asthma, with the improvement of pulse rate, systolic blood pressure, and respiratory function measurements. Furthermore, reduction in the frequency of attacks, severity, and medication requirement was also observed, with improved quality of life (QOL). In patients with chronic obstructive pulmonary disease, symptom, activity, and impact scores were improved. QOL improvement was also noted in cancer patients. Conclusions: Available evidence on pranayama indicates physiological and psychological benefits. Beneficial effects were mostly observed in patients with respiratory diseases such as bronchial asthma. It also helped those with cancer and cardiovascular disease. However, further high-quality randomized trials are required to provide definitive evidence.
  • ... Conversely, cognitive tasks that deplete attention interfere with postural balance (Balasubramaniam and Wing, 2002). Similarly, pranayama requires attending to the autonomic process of breathing (focusing on the breath) and though attention depletion due to cognitive load alters breathing (Grassmann et al., 2016), such depletion likely resets the autonomic nervous system (Jerath et al., 2006). It is possible that the attentional demands required for bringing these ordinary autonomic processes under volitional control transform these into controlled and goal-directed activity by using cognitive resources such as working memory, planning-flexibility, and inhibition. ...
    ... There could be a differential role of attention during posture and breath control practice, and these two components of yoga training likely have separable influences on executive control. Though asanas and pranayama both aim at controlling autonomic processes, others have recommended that the effects of breath control be examined separately from those of postures (Jerath et al., 2006;Trakroo et al., 2013). During posture training, the eyes are open in order to regulate movements by imitating an external referent (e.g., yoga instructor, a picture, or a video), whereas breath control exercises are performed with the eyes closed, cultivating internal awareness by curtailing external referents. ...
    ... This is mainly because the respiratory system plays a critical role in speech and articulation (Ackermann and Riecker, 2010). Next, attention toward slowing paced movements improves postural control (Wu, 2002), and slow-paced breathing has the most evident cognitive benefits (Pal and Madanmohan, 2004;Jerath et al., 2006). However, some have found that both slow-and fast-paced breathing enhances cognitive control (Sharma et al., 2014). ...
    Article
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    Malleability of executive control and its enhancement through yoga training is unclear. In Study 1, participants (yoga group; n = 27, mean = 23.27 years) were tested on executive control tasks pre and post 8 weeks of yoga training. The training focused on attention to postural control during yoga asanas and respiratory control during pranayama-breathing (30 min each of postural and breath-control training, biweekly). Yoga training was assessed via performance ratings as to how well a posture was executed and by examining errors that reflected inattention/failures in postural and breath control. We also explored whether attentional demands on motor and respiratory control were associated with three components of executive control (working memory, cognitive flexibility, and inhibition) during nine executive control tasks. Partial correlation results revealed that the three components of executive control might be differentially impacted by postural and breath control, and selectively associated with either speed or accuracy (except for cognitive flexibility). Attentional demands influenced the link between postural, breath, and cognitive control. In Study 2, comparisons between a yoga group and a gender-matched control group (control group; n = 27, mean = 23.33 years) pointed towards higher working memory accuracy and a better speed-accuracy tradeoff in inhibitory control in the yoga group. A ceiling-practice effect was addressed by examining yoga practice learning (i.e., practice-induced change in postural and breath control reflected in ratings and errors) on executive control performance across two sets of tasks: repeatedly tested (pre and post-8 weeks) and non-repeatedly tested (post-8 weeks). Attention to motor and respiratory control during yoga might be considered as a potential mechanism through which specific components of executive control in young adults might be enhanced potentially via altering of speed-accuracy tradeoff.
  • ... Da secoli, la cultura orientale e quella occidentale hanno considerato il controllo della respirazione uno degli strumenti più efficaci per lo sviluppo spirituale dell'individuo (Patanjali, Yoga Sutra). In Oriente, le tecniche respiratorie che mirano a controllare e modulare volontariamente le caratteristiche della respirazione, come la sua frequenza e la sua profondità, sono chiamate pranayama (dal sanscrito, controllo, ma anche espansione del respiro), e sono principalmente utilizzate in combinazione con diverse tecniche contemplative, come lo yoga e la meditazione (Jerath et al., 2006;Zaccaro et al., 2018a). In Occidente, negli ultimi anni, l'indagine scientifica della coscienza, soprattutto in ambito neuroscientifico, sta vivendo una notevole evoluzione, e lo studio delle tecniche contemplative orientali è spesso utilizzato come modello per comprenderne il funzionamento nei suoi stati ordinari e non ordinari. ...
    ... La prima e la più evidente caratteristica che si osserva in quasi tutte le tecniche di respirazione, sia di derivazione orientale che occidentale, è che queste preferiscono il coinvolgimento della via respiratoria nasale a quello della bocca (Ramacharaka, 1903;Iyengar, 1985;Jerath et al., 2006;Zaccaro et al., 2018a). All'interno della letteratura indiana è riportato che "solo una volta che i canali delle narici sono liberi, lo yogi diventa in grado di controllare il prana" (Hatha Yoga Pradipika), indicando che i canali energetici (nadi) delle narici sono di grande importanza per il controllo dell'energia vitale (prana) dell'organismo. ...
    ... Sulla base delle evidenze soprariportate, è possibile ipotizzare il meccanismo neurofisiologico alla base della respirazione lenta. Un primo fattore è senza dubbio il rallentamento della frequenza respiratoria stessa, e un suo immediato effetto è riscontrabile nei cambiamenti periferici del corpo, in particolare nell'aumentata dominanza del sistema nervoso parasimpatico: le vie nervose periferiche implicate trasmettono informazioni interocettive dall'organismo al sistema nervoso centrale, attraverso le proiezioni del nucleo del tratto solitario e del nucleo parabrachiale (una serie di revisioni della letteratura sono state pubblicate sull'argomento, concentrandosi in particolare sull'importanza dell'attività del nervo vago: Brown e Gerbarg, 2005;Jerath et al., 2006;Streeter et al., 2012;Brown et al., 2013;Gerritsen e Band, 2018). Occorre inoltre ricordare che la respirazione lenta è in grado di modulare l'attività del locus coeruleus, nucleo fondamentale per lo stato di arousal, l'attenzione e l'espressione emotiva (Sheikhbahaei e Smith, 2017;Yackle et al., 2017). ...
  • ... RELATED WORK rhythm (Vaschillo et al., 2006;Lehrer et al., 2000), and it has been found to reflect a balance between the two branches of the Ans, the sympathetic and parasympathetic nervous system. Deep breathing is a method to address the autonomic imbalance that arises from exposure to a stressor (Jerath et al., 2006). It recruits the parasympathetic branch of the nervous system and inhibits the sympathetic action, leading to a regulated state . ...
    ... It recruits the parasympathetic branch of the nervous system and inhibits the sympathetic action, leading to a regulated state . Regulating breathing rate towards this resonant frequency shifts the autonomic balance maximizing Hrv and down-regulates high arousal (Jerath et al., 2006;McCaul et al., 1979). Therefore, practicing Rsa through the Hrv biofeedback improves the skill-acquisition of Er by influencing physiology (Moraveji et al., 2011). ...
    Thesis
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    Emotions are thought to be one of the key factors that critically influence human decision-making. Emotion-regulation can help to mitigate emotion-related decision biases and eventually lead to a better decision performance. Serious games emerged as a new angle introducing technological methods to practicing emotion-regulation, where meaningful biofeedback information communicates player's affective states to a series of informed gameplay choices. These findings motivate the notion that in the decision context of serious games, one would benefit from awareness and regulation of such emerging emotions. This thesis explores the design and evaluation methods for creating serious games where emotion-regulation can be practiced using physiological biofeedback measures. Furthermore, it investigates emotions and the effect of emotion-regulation on decision performance in serious games. Using the psychophysiological methods in the design of such games, emotions and their underlying neural mechanism have been explored. The results showed the benefits of practicing emotion-regulation in serious games, where decision-making performance was increased for the individuals who down-regulated high levels of arousal while having an experience of positive valence. Moreover, it increased also for the individuals who received the necessary biofeedback information. The results also suggested that emotion-regulation strategies (i.e., cognitive reappraisal) are highly dependent on the serious game context. Therefore, the reappraisal strategy was shown to benefit the decision-making tasks investigated in this thesis. The results further suggested that using psychophysiological methods in emotionally arousing serious games, the interplay between sympathetic and parasympathetic pathways could be mapped through the underlying emotions which activate those two pathways. Following this conjecture, the results identified the optimal arousal level for increased performance of an individual on a decision-making task, by carefully balancing the activation of those two pathways. The investigations also validated these findings in the collaborative serious game context, where the robot collaborators were found to elicit diverse affect in their human partners, influencing performance on a decision-making task. Furthermore, the evidence suggested that arousal is equally or more important than valence for the decision-making performance, but once optimal arousal has been reached, a further increase in performance may be achieved by regulating valence. Furthermore, the results showed that serious games designed in this thesis elicited high physiological arousal and positive valence. This makes them suitable as research platforms for the investigation of how these emotions influence the activation of sympathetic and parasympathetic pathways and influence performance on a decision-making task. Taking these findings into consideration, the serious games designed in this thesis allowed for the training of cognitive reappraisal emotion-regulation strategy on the decision-making tasks. This thesis suggests that using evaluated design and development methods, it is possible to design and develop serious games that provide a helpful environment where individuals could practice emotion-regulation through raising awareness of emotions, and subsequently improve their decision-making performance.
  • ... While the article attempts to unravel some of the neural, physiological, chemical and hormonal connections, there may be other mechanisms playing a role in its effectiveness in assisting the overall health -including that of the brain. For example, Jerath et al. [7] advance the hypothesis that only the stretch receptors are responsible for the effects observed. ...
    Chapter
    The benefits of pranayama for positive health are well known. Even though there are many studies published on the effectiveness of pranayama, there are very few papers, which actually have systematically studied the physiological mechanisms involved, causing the benefits of pranayama, especially with respect to the cardiac function. This article attempts to have a detailed look at the physiology behind deep breathing. The article also conjectures that voluntary, deep breathing with attention may have a role to play in faster recovery from surgeries, and prevent or delay the onset of Alzheimer’s disease, Parkinson’s disease and may be, even cancer. Extended, carefully controlled and detailed studies are needed to prove or disprove these conjectures.
  • ... These inhibitory signals coming from cardiorespiratory region involving vagi are believed to synchronize neural elements in the brain leading to changes in the autonomic nervous system. This condition is characterized by reduced metabolism and parasympathetic dominance [7,8]. ...
    Article
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    Background: Yoga is ultimate for developing harmony among body, mind and spirit. The purpose of this study was to investigate the effect of selected yogic practice and bench step aerobics training on improving selected physiological variables of females at Wollega University. Method: Sixty female students were divided into three equal groups on random basis (groups I, II, and III) consisting of 20 study participants in each group. Two out of the three groups were given experimental treatments: yogic practice (group- I), bench step aerobics (group- II) while the remaining one group (group- III) was designated as control group. The study was formulated as completely randomized comparative trial, consisting of a pre-test and post-test. The collected data from the three group’s pretest and posttest were statistically analyzed using analysis of covariance (ANCOVA). The Least significant difference (LSD) post hoc test was applied to determine significant differences among paired mean values. The 95% level of confidence was used and p-value <0.05 was considered as statistically significant. Results: The findings of the study on physiological variables revealed that yogic practice (YP) group and bench step aerobics (BSAE) group showed significant superiority over the control group in reducing respiratory rate (p<0.05). The mean change made by the two experimental groups (p > 0.05) didn’t show statistically significant difference. The finding also revealed that YP group and BSAE group significantly improved breath holding time than control group (p>0.05). The mean change made by the two experimental groups (p<0.05) didn’t show statistically significant difference. BSAE training was found to be significantly better in decreasing resting heart rate of the study participants than YP group (Mean difference (MD)=2.18*, p < 0.05). Conclusion: The experimental groups; selected yogic practice groups (YPG) and bench step aerobics training (BSAEG) had significantly improved the selected physiological variables in contrast to control group. BSAE training was found to be significantly better on improving resting heart rate than yogic practice group and control group.
  • ... One long-term effect of pranayamic breathing is the improvement of autonomic function, specifically, with slow breathing pranayama there is a noted increase in parasympathetic activity and a decrease in sympathetic dominance. Short-term effects of slow pranayamic breathing include increased galvanic skin resistance (a non-neural response), decreased oxygen consumption, decreased heart rate, decreased blood pressure, and increased amplitude of theta waves (Jerath, Edry, Barnes, & Jerath, 2006). stretching without inducing a relaxation response for the metabolic syndrome (Kanaya et al., 2014). ...
    Thesis
    The thesis aims to investigate the effects of two techniques of emotional reglulation, mindfulness meditation and yoga, on stress reactivity, alexithymia, and its relevant variables. Forty-four healthy particiants were ramdomly allocated into 3 groups; mindfulness meditation, yoga and control. The results showed that the 8-weeks of mindfulness meditation (one session/week with an instructor and two sessions as home-practice) significantly improved mindfulness skill and concentration. While, the 8-weeks of yoga significantly ameliorated heart rate variability, (increased HF(n.u.), decreased LF(n.u.) and LF/HF). However, there was no significant interaction effect of group x time for stress hormones. Furthermore, there was no significant interaction effect of group x time for alexithymia. We add a qualitative analysis to better understand the process behind the changes following theinterventions. It indicated that the mindfulness meditation seemed to be the most effective intervention for alexithymia. Individual differences such as personality, attitudes and confidence on the effectiveness of intervention as well as the level of physical activity should be taken into account in the choice of the most appropriate intervention for a specific profile. Despite the study limitations due to the small subjects number in the different groups, it appears that mindfulness meditation and yoga seem to be an effective intervention for stress management, and mindfulness meditation would be suggested for alexithymia.
  • ... The practice of deep breathing exercises helps in increasing parasympathetic activity and reducing sympathetic activity. 21 In deep breathing exercises, lungs are expanded considerably, as the individual is in the continuous phase of inhalation with his strong voluntary control and the walls of the alveoli are stretched to the maximum extent, thus resulting in improvement in the chest compliance. Gradually, the duration of inspiration increases so that respiratory centre slowly acclimatises to withstand higher partial pressure of carbon dioxide (PCO2) and lower partial pressure of oxygen (PO2). ...
  • ... Studies reveal an increase in neuroplasticity in those who perform yoga, thereby improving concentration, intelligence quotient scores, and motor control. [22] Breathing exercises recommended in Pregnancy Pterocarpus marsupium(Vijaysaar) [23] Pterocarpus marsupium has been shown to cause pancreatic beta cell regranulation. The heartwood of the tree is used to make tumblers/ goblets/beakers which are filled with water and allowed to stand overnight to give "Beeja wood water" the positive activity of which against diabetes has been confirmed. ...
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