Below are some of the studies and literature reviews that have informed the Nervous System Mastery curriculum. A complementary skill to this course that I would recommend exploring is how to study studies. This essay series by Dr. Peter Attia is a great starting point..
👀 Interoception Studies
‘Out-of-the-blue panic attacks aren't without warning: Body sends signals for hour before’
by Southern Methodist University, 2011
“Significant autonomic irregularities preceded the onset of attacks that were reported as abrupt and unexpected. The findings invite reconsideration of the current diagnostic distinction between uncued and cued panic attacks.”
‘Interoceptive Awareness Skills for Emotion Regulation: Theory and Approach of Mindful Awareness in Body-Oriented Therapy (MABT)’
by Cynthia J. Price and Carole Hooven, in Frontiers in Psychology, 2018
“The mindful awareness in body-oriented therapy (MABT) approach offers a framework for understanding how interoceptive awareness facilitates emotion regulation. MABT develops the distinct interoceptive awareness capacities of identifying, accessing, and appraising internal bodily signals and provides an individualized protocol for scaffolding interoceptive awareness.”
‘Interoception and Social Connection’
by Andrew J. Arnold et al., in Frontiers in Psychology, 2019
“Interoception may help in appraising physiological signals in social situations and flexibility in engaging interoception in social situations may be important for regulation. This paper proposes that interventions aimed at improving interoceptive abilities may be key for alleviating loneliness and improving social connection.”
‘Increased dopamine tone during meditation-induced [NSDR] change of consciousness’
by Troels W Kjaer et al, Brain Res Cogn Brain Res, 2002
During meditation, 11C-raclopride binding in ventral striatum decreased by 7.9%. This corresponds to a 65% increase in endogenous dopamine release.
🫁 Studies on Self-Regulation Protocols
‘Brief structured respiration practices enhance mood and reduce physiological arousal’
by Melis Yilmaz Balban, Eric Neri, Manuela M. Kogon, Jamie M. Zeitzer, David Spiegel & Andrew D. Huberman
“This experimental study investigated the effects of three different 5-min daily breathwork exercises on mood, anxiety, and physiological arousal. It found that cyclic sighing produced greater improvement in mood and reduction in respiratory rate compared to mindfulness meditation.”
‘The Integrative Role of the Sigh in Psychology, Physiology, Pathology, and Neurobiology’
by Jan-Marino Ramirez, in Progress in Brain Research, 2014
“Hypoarousal and failure to sigh have been associated with sudden infant death syndrome. Increased breathing irregularity may provoke excessive sighing and hyperarousal, a behavioral sequence that may play a role in panic disorders. Essential for generating sighs and breathing is the pre-Bötzinger complex.”
‘The Polyvagal Perspective’
by Stephen W Porges
The polyvagal perspective emphasizes how an understanding of neurophysiological mechanisms and phylogenetic shifts in neural regulation, leads to different questions, paradigms, explanations, and conclusions regarding autonomic function in biobehavioral processes than peripheral models.
‘Effect of breathing exercises on oxidative stress biomarkers in humans: A systematic review and meta-analysis’
by Ting-ting Li et al., in Frontiers of Psychology, 2023
Breathing exercises have been shown to significantly reduce oxidative stress biomarkers in humans.
‘Breathwork Interventions for Adults with Clinically Diagnosed Anxiety Disorders: A Scoping Review’
by Blerida Banushi et al., in Brain Sciences, 2023
This examination of the efficacy of breathwork interventions for adults with clinically diagnosed anxiety disorders finds that breathwork interventions yielded significant improvements in anxiety symptoms and supports the clinical utility of breathwork interventions.
‘Heart Rate Variability as an Index of Resilience’
by Eric An et al., in Mil Med, 2020
Flexibility of the autonomic nervous system is particularly important for adaptive stress responses and may contribute to individual differences in resilience. By analysing heart rate variability (HRV), this study evaluates the link between autonomic flexibility (regulation) and sympathovagal balance (resilience).
‘Amygdala-driven apnea and the chemoreceptive origin of anxiety’ by Feinstein et al 2022’
by Justin S. Feinstein et al., in Biological Psychology, 2022
This paper proposes a model of Apnea-induced Anxiety which suggests that recurring episodes of apnea are being unconsciously elicited by amygdala activation, leading to fear and anxiety, which suggests the chemical basis for anxiety and can support anxiety-reducing interventions.
‘Effect of a slow-paced breathing with heart rate variability biofeedback intervention on pro-inflammatory cytokines in individuals with panic disorder - A randomized controlled trial’
by Benedict Herhaus et al., in Journal of Affective Disorders, 2023
Based on recent evidence that slow-paced breathing (SPB) and heart rate variability-biofeedback (HRV-BF) can strengthen the nervus vagus’ anti-inflammatory pathway, these researchers studied the effects of decreasing certain pro-inflammatory cytokines in the reduction of cardiovascular diseases and metabolic syndrome.
‘Self-Regulation of Breathing as a Primary Treatment for Anxiety’
by Ravinder Jerath et al., in Applied Psychophysiology and Biofeedback, 2015
“We hypothesize that reversing homeostatic alterations with meditation and breathing techniques rather than targeting neurotransmitters with medication may be a superior method to address the whole body changes that occur in stress, anxiety, and depression.”
‘Effect of breathwork on stress and mental health: A meta-analysis of randomised-controlled trials’
by Guy William Fincham et al., in Scientific Reports, 2022
This meta-analysis studied the effect of breathwork on stress and mental health and found that breathwork was associated with lower levels of stress, anxiety, and depressive symptoms compared to control conditions.
‘The Impact of Resonance Frequency Breathing on Measures of Heart Rate Variability, Blood Pressure, and Mood’
by Patrick R. Steffen et al., in Front Public Health, 2017
Heart rate variability biofeedback (HRVB) significantly improves heart rate variability (HRV). Breathing at resonance frequency (RF, approximately 6 breaths/min) constitutes a key part of HRVB training and is hypothesized to be a pathway through which biofeedback improves HRV.
‘The Effect of Diaphragmatic Breathing on Attention, Negative Affect and Stress in Healthy Adults’
by Xiao Ma et al., in Frontiers of Psychology,2017
“A number of studies have revealed that diaphragmatic breathing may trigger body relaxation responses and benefit both physical and mental health. This study provided evidence demonstrating the effect of diaphragmatic breathing, a mind-body practice, on mental function, from a health psychology approach, which has important implications for health promotion in healthy individuals.”
‘Alternating cerebral hemispheric activity and the lateralization of autonomic nervous function’
by Werntz D A et al., in Human Neurobiology, 1983
The ‘nasal cycle’ is where breathing alternates between the right and left nostril. Adopting the nasal cycle has been shown to integrate EEG value in one hemisphere of the brain with predominant airflow in the contralateral nostril, which defines a new interrelationship between cerebral dominance and peripheral autonomic nervous function.
‘Effects of voluntary slow breathing on heart rate and heart rate variability: A systematic review and a meta-analysis’
by Laborde S et al., in Neuroscience & Biobehavioural Reviews, 2022
Although a lot of empirical research suggests that slow breathing can be used as a prevention technique to support physical and mental health, little research has been done on the effects on heart-rate variability and its link with health outcomes. This paper conducts a systematic review and meta-analysis of the current literature.
🫁 Emotional & Co-regulation Studies
‘Somatic experiencing: using interoception and proprioception as core elements of trauma therapy’
by Peter Payne et al., in Frontiers in Psychology, 2015
Somatic Experiencing is designed to direct the attention of the person to internal sensations that facilitate biological completion of thwarted responses, thus leading to resolution of the trauma response and the creation of new interoceptive experiences of agency and mastery.
‘Breathing Rhythm and Pattern and Their Influence on Emotion’
by Sufyan Ashhad et al., in Annual Review of Neuroscience, 2022
This paper discusses the complex neural control system of breathing, and its connectivity to emotion and cognition and suggests that breathing has a broad influence on the brain and body.
‘Cellular allostatic load is linked to increased energy expenditure and accelerated biological aging’
by Natalia Bobba-Alves et al., in Psychoneuroendocrinology, 2023
Studying the effects of allostatic load on cellular energy expenditure has found that chronic glucocorticoid exposure increases energy expenditure and is linked to mtDNA instability, accelerated cellular aging, and reduced lifespan, and thus suggests that increased stress is linked to accelerated biological aging.
‘Relationship between interoception and emotion regulation: New evidence from mixed methods’
by Giorgia Zamariola et al., in Journal of Affective Disorders, 2019
Interoception is the ability to perceive one's inner bodily feelings and is thought to be associated with the capacity of recognising and experiencing emotions. This study looks at interoception from the individuals’ perspective.
‘A new measure of feeling safe: Developing psychometric properties of the neuroception of psychological safety scale (NPSS)’
by Liza Morton et al., in Psychological Trauma: Theory, Research, Practice, and Policy, 2022
Psychological safety is increasingly recognized as central to mental health, wellbeing and posttraumatic growth. The NPSS is a novel measure of psychological safety which can be used across a range of health and social care settings. The NPSS will help shape new approaches to evaluating trauma treatments, relational issues and mental health concerns.
‘Brain Waves Synchronize when People Interact’
by Lydia Denworth, in Scientific American, 2023
To date, neuroscientists usually investigate one brain at a time. Now, collective neuroscience, as some practitioners call it, is a rapidly growing field of research. An early, consistent finding is that when people converse or share an experience, their brain waves synchronize.
