Effects of Yoga Respiratory Practice (Bhastrika pranayama) on Anxiety, Affect, and Brain Functional Connectivity and Activity: A Randomized Controlled Trial

Abstract

Pranayama refers to a set of yoga breathing exercises. Recent evidence suggests that the practice of pranayama has positive effects on measures of clinical stress and anxiety. This study explored the impact of a Bhastrika pranayama training program on emotion processing, anxiety, and affect. We used a randomized controlled trial design with thirty healthy young adults assessed at baseline and after 4 weeks of pranayama practices. Two functional magnetic resonance imaging (MRI) protocols were used both at baseline and post-intervention: an emotion task as well as a resting-state acquisition. Our results suggest that pranayama significantly decreased states of anxiety and negative affect. The practice of pranayama also modulated the activity of brain regions involved in emotional processing, particularly the amygdala, anterior cingulate, anterior insula, and prefrontal cortex. Resting-state functional MRI (fMRI) showed significantly reduced functional connectivity involving the anterior insula and lateral portions of the prefrontal cortex. Correlation analysis revealed that changes in connectivity between the ventrolateral prefrontal cortex and the right anterior insula were associated with changes in anxiety. Although it should be noted that these analyses were preliminary and exploratory, it provides the first evidence that 4 weeks of B. pranayama significantly reduce the levels of anxiety and negative affect, and that these changes are associated with the modulation of activity and connectivity in brain areas involved in emotion processing, attention, and awareness. The study was registered at https://www.ensaiosclinicos.gov.br/rg/RBR-2gv5c2/(RBR-2gv5c2).

Combining transcranial magnetic stimulation with functional magnetic resonance imaging for probing and modulating neural circuits relevant to affective disorders

“…org/) is a good starting point for information that should be included in manuscripts describing randomized trials. There is an increasing trend of including CONSORT diagrams in studies of affective disorders with neuroimaging (Mehler et al, 2018;Novaes et al, 2020;Siegle et al, 2012). A CONSORT diagram transparently reports the intended study population and actual analytic sample that remained after participants dropped out and poor-quality images were discarded.…”

Perceived stress, resilience, well-being, and COVID 19 response in Isha yoga practitioners compared to matched controls: A research protocol

“…In a systematic review [ 39 ] which investigated the effects of yoga on sympathetic nervous system and hypothalamic pituitary adrenal axis regulation measures, evidence suggested that yoga practice led to improved regulation of these systems and decreased depression and anxiety symptoms. Similarly, in a recent study of a yogic breathing protocol on emotion processing, anxiety, and affect, thirty individuals were assessed at baseline and after 4 weeks of practice [ 40 ]. Functional magnetic resonance imaging (MRI) showed significantly decreased states of anxiety and negative affect at follow-up, and the modulation of activity in brain regions involved in emotional processing, attention, and awareness.…”

Causal relations between cortical network oscillations and breathing frequency

“…LFP phase-locking to respiratory cycles includes regions not primarily related to olfaction (Ito et al, 2014;Lockmann et al, 2016;Nguyen Chi et al, 2016;Zelano et al, 2016;Biskamp et al, 2017;Herrero et al, 2018;Karalis and Sirota, 2018;Kőszeghy et al, 2018;Rojas-Líbano et al, 2018;Tort et al, 2018b), suggesting that respiration-entrained oscillations aid the integration of widespread information (Heck et al, 2017(Heck et al, , 2019Tort et al, 2018a), similar to the proposed function of other slow network rhythms (Isomura et al, 2006;Canolty and Knight, 2010). Given the alleged beneficial effects of some respiratory practices to mood, behavioral performance, and cognitive abilities (Pascoe and Bauer, 2015;Zelano et al, 2016;Melnychuk et al, 2018;Nakamura et al, 2018;Perl et al, 2019;Novaes et al, 2020), the fact that nasal respiration can modulate brain oscillations in non-olfactory regions has sparked large interest, including in popular science media, since it could provide a way through which respiration would affect brain functions (Heck et al, 2017;Varga and Heck, 2017;Tort et al, 2018a).…”