Slow nasal breathing selectively modifies state of consciousness in healthy humans: a psychometric study

Abstract

Introduction: Neurophysiological studies in animal models and in humans revealed that mechanical stimulation of olfactory epithelium via odourless air synchronizes neuronal rhythms in cortical and subcortical areas. A study from our group found that “passive” ultra-slow mechanical stimulation of olfactory epithelium alters the state of consciousness in healthy subjects by slowing cerebral rhythms in higher-order areas (e.g. Default Mode Network). The aim is to investigate the role of “active” (i.e. guided by top-down attention) slow nasal breathing on consciousness states.
Methods: Sixteen healthy volunteers, with a mean of 1700 hour of Pranayama practice, performed 15 min of Samavritti Pranayama at 2.5 b/min through the nose. As control condition, the same session was performed breathing only through the mouth. Before and after each session, the state of consciousness was measured through the Clinician Administered Dissociative States Scale and the Phenomenology of Consciousness Inventory. Data were analysed with a two-factor (pre/post, nose/mouth) repeated measures ANOVA.
Results: Only nasal breathing increased dissociative state (p<0.01) and altered the state of consciousness (p<0.01), with increased introspection (p<0.01) and altered body perception (p<0.05).
Conclusions: A breathing-related nasal mechanical stimulation specifically leads to meditative-like, altered state of consciousness.

Full text

Slow nasal breathing selectively modifies state of consciousness in
healthy humans: a psychometric study
Andrea Zaccaro1, Danilo Menicucci1, Alice Zito1, Lorenza Melosini2,
Andrea Piarulli1, Angelo Gemignani1,
1 University of Pisa, Department of Surgical- Medical and Molecular Pathology and Critical Care Medicine, Pisa, Italy
2 Azienda Ospedaliero-Universitaria Pisana, Dipartimento Cardio Toraco Vascolare, Pisa, Italy
To investigate the role of “active” (i.e. guided by top-down attention) slow
nasal breathing on consciousness states, directly comparing nasal and
mouth breathing in a group of expert Pranayama practitioners
A breathing-related, nasal
mechanical stimulation
specifically leads to
meditative-like, altered
state of consciousness
Correlation with altered state of consciousness
Delta activity Theta activity
Phenomenolgy of
Cosciousness Inventory,
Pekala, 1991
PCC/Precuneus l-rOA, PHG, EC
MPFC, OFC
Piarulli et al., 2018
Negativa Positiva
   -   |
   -  || 
||
“Only once the nostril channel, usually obstructed by
impurities, is free, the yogi can become able to control the
Prana”
Sample
16 healthy volunteers, Pranayama experts
(12 females, mean age 48y)
State tests
State-Trait Anxiety Inventory (STAI-Y), Positive and Negative Affect
Schedule (PANAS), Clinician-Administered Dissociative State Scale
(CADSS)
Retrospective tests
Amsterdam Resting-State Questionnaire (ARSQ 2.0),
Phenomenology of Consciousness Inventory (PCI)
Electrophysiology
Respirogram (thoracic and abdominal belts)
High density EEG (128 channels)
ECG
Statistics
Repeated-measures ANOVA, two factors within
subjects
Inhalation (6 secs)
Pause (6 secs)
Exhalation (6 secs)
Pause (6 secs)
Retrospective tests
- subscales
PCI: Altered state of consciousness
0.009
PCI: Joy
0.004
PCI: Direction of attention/Introspection
0.004
PCI: Altered body perception
0.049
PCI: Unusual meanings (“sacredness of the experience”)
0.006
ARSQ: Somatic awareness
0.009
State test
p-
value
CADSS
0.003
Nasal
breathing
Post slow nasal breathing VS slow mouth breathing
Power spectral density (N=1)
delta
alpha beta
theta
gamma
Delta (1-4 Hz), Theta (4-8 Hz), Alpha
(8-12 Hz), Beta (12-30 Hz) and
Gamma (30-45 Hz)
STATE TESTS
5 min spontaneous
breathing (NOSE)
RETROSPECTIVE TESTS
15 min Slow
Breathing
(NOSE)
15 min Slow
Breathing
(MOUTH)
MOUTH BREATHING SESSION
NASAL BREATHING SESSSION
STATE AND
RETROSPECTIVE TESTS
5 min
spontaneous
breathing (NOSE)
5 min
spontaneous
breathing (NOSE)
5 min
spontaneous
breathing (NOSE)
5 min
spontaneous
breathing (NOSE)
Breath frequency: 2.5 breaths/min (0.04 Hz)
Nasal
breathing
Nasal
breathing
Nasal
breathing
Nasal
breathing
Nasal
breathing
Nasal
breathing
Post slow nasal breathing VS slow mouth breathing
Repeated-measures ANOVA (N=16)
Slow mechanical stimulation of nasal vault through air puffs
Neurophysiological studies in animal models and in humans reveal
that mechanical stimulation of olfactory epithelium via odourless air
synchronizes neuronal rhythms in cortical and subcortical areas
A study from our group found that “passive”, ultra-slow mechanical
stimulation of olfactory epithelium alters the state of consciousness in
healthy subjects by slowing cerebral rhythms in higher-order areas (e.g.
Default Mode Network)
INTRODUCTION
Fontanini and Bower, 2006
AIM AND METHODS RESULTS AND DISCUSSION
Slow breathing technique: Samavritti Pranayama