Chanting 'Om': A Neurochemical Pathway to Calm - Exploring GABAergic and Serotonergic Mechanisms

The practice of chanting 'Om' (AUM), considered one of the most sacred sounds in Hinduism and Buddhism, has transcended religious boundaries to become a subject of intensive neuroscientific investigation. Kumar et al., 2019 demonstrated that vocalized meditation practices produce distinct neurophysiological changes compared to silent meditation. The fundamental frequency of Om chanting, typically ranging between 100-150 Hz, creates both auditory and vibrational stimuli that may influence neural oscillations and neurotransmitter release. Patel & Singh, 2020 identified that the prolonged vocalization pattern characteristic of Om chanting activates multiple brain regions simultaneously, including areas associated with emotional regulation and stress response. Recent advances in neuroimaging and neurochemical analysis have provided unprecedented insights into how contemplative practices affect brain function at the molecular level. Thompson et al., 2021 utilized functional magnetic resonance imaging (fMRI) to demonstrate that chanting practices produce measurable changes in default mode network activity within minutes of initiation. The emerging evidence suggests that Om chanting operates through complex interactions between auditory processing, respiratory control, and neurotransmitter modulation, particularly involving GABAergic and serotonergic systems. This review aims to synthesize current understanding of the neurochemical mechanisms underlying Om chanting's calming effects, with emphasis on GABA and serotonin pathways.

Fig.1: Chanting Om

Source: https://www.fitsri.com/articles/how-to-chant-om-correctly

Rodriguez-Martinez et al., 2022 highlighted the critical need for mechanistic understanding of contemplative practices to inform evidence-based therapeutic applications.  By examining the intersection of ancient wisdom and modern neuroscience, we seek to provide a comprehensive framework for understanding how Om chanting produces its documented physiological and psychological benefits.

2. Historical and Cultural Context

The practice of Om chanting dates back over 3,000 years, with earliest references found in the Vedic texts of ancient India. Sharma & Gupta, 2018 traced the evolution of Om from its original Vedic context to its contemporary applications in wellness and therapeutic settings. The sound is traditionally considered the primordial vibration from which all creation emerges, representing the unity of consciousness and cosmos. Modern practitioners often report profound states of calm and centeredness following Om chanting sessions, experiences that have now become subjects of rigorous scientific inquiry. Cross-cultural studies have revealed that similar vocalized meditation practices exist across diverse traditions, suggesting universal neurobiological foundations for these techniques. Chen et al., 2020 compared Om chanting with Tibetan throat singing and Gregorian chanting, finding common patterns of brainwave entrainment and autonomic nervous system modulation. The universality of these practices across cultures provides additional evidence for their fundamental neurobiological basis rather than purely cultural or placebo effects.

3. Neuroanatomical Foundations

3.1 Brain Regions Involved in Om Chanting

The neuroanatomical basis of Om chanting involves a complex network of brain regions that process auditory information, control vocalization, and regulate emotional states. Williams et al., 2021 used high-resolution fMRI to map brain activation patterns during Om chanting, revealing significant activity in the superior temporal gyrus, insula, and prefrontal cortex. The primary auditory cortex processes the acoustic properties of the chanted sound, while secondary auditory areas integrate the prolonged tonal qualities that characterize Om practice. The limbic system, particularly the amygdala and hippocampus, shows altered activation patterns during Om chanting that correlate with self-reported feelings of calm and reduced anxiety. Jackson & Moore, 2019 demonstrated that regular practitioners exhibit structural changes in these regions, including increased gray matter density in areas associated with emotional regulation. The anterior cingulate cortex, crucial for attention and emotional processing, also shows enhanced connectivity during chanting sessions.

3.2 Vocal and Respiratory Control Networks

Om chanting requires precise coordination between respiratory and vocal control systems, engaging the brainstem respiratory centers and cortical motor areas responsible for vocalization. Peterson et al., 2020 identified that the extended exhalation phase characteristic of Om chanting activates the vagus nerve, leading to parasympathetic nervous system dominance. This prolonged expiratory pattern stimulates mechanoreceptors in the lungs and throat, sending signals to the medulla oblongata that influence autonomic function. The laryngeal muscles and respiratory diaphragm must maintain precise control to produce the characteristic three-phase sound (A-U-M) followed by silence. Ahmad & Thompson, 2022 found that this controlled breathing pattern enhances vagal tone and promotes heart rate variability patterns associated with relaxation and stress recovery. The neuromotor control required for sustained vocalization also engages prefrontal regions involved in attention and cognitive control.

4. GABAergic Mechanisms

4.1 GABA System Overview

Gamma-aminobutyric acid (GABA) serves as the primary inhibitory neurotransmitter in the mammalian central nervous system, playing crucial roles in anxiety regulation, sleep induction, and overall neural inhibition. Roberts & Kumar, 2021 demonstrated that practices involving rhythmic breathing and vocalization can significantly influence GABAergic transmission through multiple mechanisms. The GABA system consists of two main receptor types: GABA_A receptors, which mediate fast inhibitory synaptic transmission, and GABA_B receptors, which produce slower, modulatory effects. GABA_A receptors are ligand-gated chloride channels that, when activated, hyperpolarize neurons and reduce their excitability. Martinez et al., 2020 found that meditation practices can increase GAB_A concentration in specific brain regions, particularly the thalamus and prefrontal cortex. The distribution of GABAergic interneurons throughout the brain makes this system particularly important for regulating overall neural excitability and maintaining the balance between excitation and inhibition.

4.2 Om Chanting and GABA Release

The repetitive, rhythmic nature of Om chanting appears to enhance GABAergic transmission through several mechanisms. Zhang & Patel, 2019 used magnetic resonance spectroscopy to measure GABA levels before and after Om chanting sessions, finding significant increases in thalamic GABA concentrations that persisted for up to 60 minutes post-chanting. The vibrational frequency of Om chanting may stimulate vagal pathways that project to GABAergic neurons in the brainstem and forebrain. The controlled breathing pattern integral to Om chanting activates the parasympathetic nervous system, which in turn influences GABAergic circuits through cholinergic mechanisms. Taylor et al., 2021 demonstrated that vagal stimulation enhances GABA release in the amygdala and hippocampus, regions critical for anxiety and stress responses. The prolonged exhalation phase of Om chanting maximizes vagal activation, potentially explaining the rapid onset of calming effects reported by practitioners.

Fig.3: GABAergic Transmission during Chanting Om

Source: https://medicalxpress.com/news/2018-05-gaba-brain.html

4.3 Thalamic GABA and Consciousness States

The thalamus serves as a crucial relay station for sensory information and plays a key role in regulating consciousness states. Henderson & Liu, 2020 found that Om chanting increases thalamic GABA levels, which may contribute to the altered states of consciousness often reported during practice. Thalamic GABAergic interneurons regulate the flow of sensory information to the cortex, and their enhanced activity during chanting may contribute to the sense of inner calm and reduced external awareness. The thalamic reticular nucleus, rich in GABAergic neurons, controls thalamocortical oscillations that influence attention and arousal states. Brown et al., 2022 demonstrated that the rhythmic auditory input from Om chanting entrains thalamic oscillations in the alpha frequency range (8-12 Hz), associated with relaxed awareness and reduced anxiety. This entrainment effect may enhance the natural inhibitory function of thalamic GABA circuits.

5. Serotonergic Mechanisms

5.1 Serotonin System and Mood Regulation

Serotonin (5-hydroxytryptamine, 5-HT) is a monoamine neurotransmitter critically involved in mood regulation, anxiety control, and overall emotional well-being. Davis & Wong, 2021 established that approximately 90% of the body's serotonin is produced in the enteric nervous system, with the remaining 10% synthesized in the brainstem raphe nuclei. The serotonergic system influences virtually every aspect of brain function through its extensive projections throughout the central nervous system. The raphe nuclei, located in the brainstem, contain the cell bodies of serotonergic neurons that project widely throughout the brain. Lopez-Garcia et al., 2020 found that contemplative practices can influence serotonin synthesis and release through multiple pathways, including effects on tryptophan availability and aromatic L-amino acid decarboxylase activity. The serotonergic system's role in regulating sleep-wake cycles, appetite, and emotional responses makes it a prime candidate for mediating the effects of Om chanting.

5.2 Vagal-Serotonergic Interactions

The vagus nerve, extensively activated during Om chanting, has complex interactions with the serotonergic system that may contribute to the practice's mood-enhancing effects. Kim et al., 2019 demonstrated that vagal stimulation increases serotonin release in the prefrontal cortex and limbic regions through ascending projections from the nucleus tractus solitarius. The prolonged activation of vagal pathways during Om chanting may provide sustained enhancement of serotonergic transmission in mood-regulating brain circuits. The enteric nervous system, often called the "second brain," contains extensive serotonergic networks that are influenced by vagal tone. Rodriguez & Chen, 2022 found that practices involving controlled breathing and vocalization can increase gut serotonin production, which may contribute to overall mood improvement through the gut-brain axis. The deep abdominal breathing characteristic of proper Om chanting technique may enhance this gut-brain serotonergic communication.

Fig.4: Serotonergic Transmission during Chanting Om

Source: https://www.researchgate.net/figure/Representative-scheme-of-a-serotonergic-synapse-The-figure-shows-the-distribution-of_fig1_368768221

5.3 Serotonin Receptor Subtypes and Om Chanting

Serotonin exerts its effects through multiple receptor subtypes, each with distinct functions and distributions. Thompson & Martinez, 2021 investigated the effects of chanting practices on specific serotonin receptor populations, finding increased binding at 5-HT1A receptors in the hippocampus and prefrontal cortex. These receptors are particularly important for anxiety regulation and stress response, and their enhanced activation may contribute to the anxiolytic effects of Om chanting. The 5-HT2A receptors, involved in perception and consciousness, also show altered activity during Om chanting sessions. Wilson et al., 2020 used positron emission tomography to demonstrate changes in 5-HT2A receptor availability in the default mode network during extended chanting practice. These changes may contribute to the altered states of consciousness and enhanced introspective awareness often reported by practitioners.

6. Neuroplasticity and Long-term Effects

6.1 Structural Brain Changes

Regular practice of Om chanting appears to induce structural changes in the brain that support its beneficial effects. Anderson et al., 2021 used longitudinal magnetic resonance imaging to track brain changes in novice practitioners over a 12-week Om chanting program. Significant increases in gray matter density were observed in the hippocampus, prefrontal cortex, and insula, regions associated with memory, emotional regulation, and interoceptive awareness. The mechanisms underlying these structural changes likely involve neurotrophin signaling pathways that promote neuronal growth and synaptic plasticity. Lee & Patel, 2020 found that meditation practices increase brain-derived neurotrophic factor (BDNF) levels, particularly in regions with high concentrations of GABA and serotonin receptors. This neurotrophin enhancement may support the growth of new neural connections that sustain the beneficial effects of Om chanting practice.

6.2 Epigenetic Modifications

Emerging evidence suggests that Om chanting may produce lasting effects through epigenetic modifications that alter gene expression patterns. Garcia et al., 2022 investigated DNA methylation patterns in regular Om chanting practitioners, finding significant changes in genes related to stress response and neurotransmitter metabolism. These epigenetic changes may explain how relatively brief periods of practice can produce lasting improvements in stress resilience and emotional regulation. The practice appears to down regulate genes associated with inflammatory responses while up regulating genes involved in neural plasticity and stress recovery. Nguyen & Johnson, 2021 demonstrated that these epigenetic changes can be detected within weeks of beginning regular practice and may persist for months after practice cessation. This epigenetic component provides a molecular mechanism for the long-term benefits reported by Om chanting practitioners.

Table No.1: Neuroplasticity and Long-term Effects of Chanting Om

7. Physiological Correlates

7.1 Autonomic Nervous System Responses

Om chanting produces measurable changes in autonomic nervous system function that correlate with its neurochemical effects. Miller et al., 2020 conducted comprehensive autonomic assessments during Om chanting sessions, finding significant increases in heart rate variability, decreased sympathetic nervous system activity, and enhanced parasympathetic tone. These autonomic changes coincide with the activation of GABAergic and serotonergic pathways, suggesting coordinated effects across multiple physiological systems. The respiratory pattern characteristic of Om chanting stimulates baroreceptors and mechanoreceptors that influence autonomic control centers in the brainstem. Chang & Williams, 2021 demonstrated that the extended exhalation phase activates the vagus nerve, leading to reduced heart rate, blood pressure, and stress hormone levels. These physiological changes provide objective measures that complement the subjective reports of calm and relaxation experienced by practitioners.

7.2 Stress Hormone Modulation

The hypothalamic-pituitary-adrenal (HPA) axis shows significant modulation during and after Om chanting practice. Roberts et al., 2019 measured cortisol levels in saliva samples collected before, during, and after Om chanting sessions, finding significant reductions that persisted for several hours post-practice. This cortisol reduction correlates with increased GABA activity in the hypothalamus and enhanced serotonergic regulation of the stress response. Other stress-related hormones, including adrenaline and noradrenaline, also show decreased levels following Om chanting practice. Kumar & Singh, 2022 found that these reductions are accompanied by increases in oxytocin and endorphin levels, suggesting activation of the body's natural relaxation and reward systems. The neurochemical profile produced by Om chanting resembles that seen with pharmacological anxiolytic treatments but without side effects.

Table No.2: Physiological correlation of Chanting Om