INTRODUCTION:

The basic understanding of the physiology of controlled breathing and its effect on inducing relaxation helps in promoting psycho-behavioral outcomes. The understood fact is that emotions affect the body. The simple example here when an individual is happy the angles of mouth mechanically turn up, and the eyes crease in a characteristic expression. Seeing emotional effects in another angle when an individual feels calm and at rest, their breathing slows and deepens, which is an influence of the parasympathetic nervous system that induces a relaxed state of the body. When individuals feel frightened or facing uncomfortable situations their breathing speeds up and becomes shallow as it is influenced by the sympathetic nervous system. The sympathetic nervous system is responsible for body reactions to people to in confronting stress.

The well-known behavioral technique relaxation is a vital mechanism that paves up to slow breathing and manage the psycho-physiological homeostasis. The pieces of evidence in the past literature reveals that the psycho-physiological changes that take place in brain-body interaction, which leads to voluntarily slowing down of breath frequencies observed in meditational and relaxation practices [1]. Breath control and psychophysiological effects are still under debate. This review study intended to develop more awareness regarding psychophysiological mechanisms of breath control.

The mental functions and breathing is closely associated with health and fitness. Over the past 1,000 years in the traditions of the east. The act of breathing is considered an essential aspect for reaching the meditative state of consciousness. In the previous literature, pieces of evidence reveal that in meditation, the rising and expansion of breath is practiced. These breathing techniques also used in clinical practices, which aim directly and consciously regulating respiratory patterns. These breathing techniques also used in clinical practices, which aim directly and consciously regulating respiratory patterns. [2]

Psychophysiological effects of slow breathing:

Prices of pieces of evidence in the previous literature on the scientific readings related to meditative neuroscience reveal progressing neural correlates of contemplative mental states. [3] Thomson had signified, causing changes in brain activity and its importance in the interventional approach that reports of mental and somatic effects elicited by meditation. [3]

The heterogeneity of meditative techniques observed in the various pieces of literature has analyzed in this study. Some of the evidential facts demonstrated building the standardized taxonomy of meditation techniques neuroelectric and neuroimaging correlates of meditation, reviews evidencing neuroelectric and neuroimaging findings that include some of the early correlates which in Buddhist practices. [4] Another supportive study has evidenced the physiological and neurobiological effects of meditational practices. [5] Additional evidence shows collation of meditation methods choosing the domains of effect and cognition. [6] The explored facts reveal that the technological advances in neuroimaging methods, findings from meditative neuroscience related to mental processes, and brain mechanisms of mindfulness practices must be reported to maintain its quality. [7]

The psychophysiological correlates of meditation practices are explored in neuroimaging studies evidenced in the activation basal ganglia, limbic system, and medial prefrontal cortex. The different meditative techniques have evidenced the important cortical network serving as a means to meditation. [8] The current literature has analyzed the anatomical probability that gets altered due to the meditational effect. The conducted meta-analysis study has found eight brain regions consistently altered in meditators, include sensory cortices and insula, hippocampus, anterior and midcingulate; orbitofrontal cortex, superior longitudinal fasciculus; corpus callosum. [9] The breathing technique or the meditation practice brings the changes in functional and structural brain observed in meditators, the specific effect evidenced in the areas tangled with self-awareness and self-regulation. This evidential literature study has explored the underlying positive pervasive biological effect of meditation practice. Also, this study recommends the meditation techniques for the clinical populations and to prevent disease. [10]

One of the past pieces of literature on the systematic review reveals that the mindfulness is associated with enhancing alpha and theta power; these outcomes are not uniformly reported. [11] The consistent patterns are not observed with the beta, delta, and gamma. This literature has revealed mindfulness is associated with increased alpha and theta power in both healthy individuals and also in patients. The elevated alpha and theta may indicate a state of relaxation; these changes are favorable to mental health. [12] One of the evidential studies has analyzed the mindfulness practice enhances attention. Further, pieces of evidence reveal the anterior cingulate cortex, the region associated with attention, in which the structural and functional changes are observed in response to mindfulness. [12] Mindfulness in stressed, anxious, and healthy subjects increases their brain activity in the prefrontal cortex, the cingulate cortex, the insula, and the hippocampus. At the same time, the amygdala showed decreased functional activity, improved functional connectivity with the prefrontal cortex. [13]

The meditative effect, on physiological functions, particularly in cardiovascular outcomes, evidences positive effects. The studies evidence the positive effects of meditation and breathe control practices in cognitive and neuropsychological outcomes. [5] The researches have proven meditative techniques in the treatment area of preclinical and clinical conditions, that mindfulness training could enhance several domains of attention, specifically domains of memory and executive functions. Researches have analyzed that various aspects of mindfulness training have different effects on cognition. [14] Pieces of evidence have revealed that mindfulness interventions have demonstrated improved outcomes in chronic pain, depression relapse, and substance addiction. [15]

Previous literature analysis recognizes that breathing techniques are closely connected with cognitive aspects of breath control practices. Most of the eastern cultures use breathing techniques that melded with cognitive aspects for achieving altered states of consciousness. [1] Studies have explored that breathing control has beneficial effects on a person's health, such as wellness, stress, and relaxation. Studies have shown meditative/breathing control practices, their mechanisms underlying effects that are separate from breathing control, which is allied with non-respiratory cognitive components such as focused attention and mental imagery. [1] The evidence in the past literature reveals various health benefits gained through the techniques of breath control practiced in the Eastern culture, breathing control recognize as a common psychophysiological model [16].

The studies on slow breathing practices of the east currently have increased its fame in the west for its outstanding health benefits, though not much consider in the medical community [17]. The studies have proven the pranayama effect on health and cognitive functions. [18] Breath control practice is proven to have psychophysiological benefits. [19,20] The shreds of evidence in the past reveal pranayama one classical method of breath control found effective in changing psychophysiological dynamism. [21,22] One of the previous studies related to neurophysiological and neurocognitive mechanisms reveals yogic exercises related to breathing control is a growing interest within the scientific community, which signifies yoga-based interventions that produce measurable changes in physiological parameters, perceived emotional states, and cognitive functioning. [23]

The benefits psychophysiological effects of slow breathing techniques:

Less than ten breaths per minute are known as slow breathing seen in transcendental meditation. The breath control techniques direct attention to the act of breathing, which includes breath awareness, breath counting, and slow breathing, and so on is a consequence of attention. The literature studies reveal healthy humans practicing with the voluntary modulation of paced breathing pave up to the improved behavioral output. Pieces of evidence from the literature explore the changes of physiological parameters related to central and autonomic nervous systems activity in slow breathing techniques trials and their relationships with behavioral outputs. [23]

The common benefits of psychophysiological effects of slow breathing techniques measured in different ways. The current study analyses the previous literature on a physiological outcome was assessed and measured of cardio-respiratory system or central nervous system observing and using Electroencephalogram, Functional Magnetic Resonance Imaging, Respiratory Sinus Arrhythmia, Heart Rate Variability and Cardio-Respiratory Synchronization composed with a psychological/behavioral outcome. [1] The intervention breathing exercises used active emotional induction fear, anger, or stress to measure a physiological parameter that impacts a psychological/behavioral outcome. [24] The literature on proper breathing evidenced better health, stress reduction, insomnia prevention, emotion control, improved attention—certain breathing techniques can make life better. [25]

Slow paced breathing and the cardio-respiratory system:

The literature demonstrates slow-paced breathing affects the cardio-respiratory parameters and its behavioral outcome. The evidential literature observed on cardio-respiratory parameters and psychological/behavioral outcomes related to slow-paced breathing; one study shows the paced breathing sessions at 6 b/min with different inspiration/expiration ratios and HRV in the Low-Frequency power.[26]

Past literature explores, physiological variables and psychological/behavioral outcomes, on using single-item scales, participant’s reports revealed in this study the strongest perceived ease and comfort level in association with the breathing condition characterized by the highest SDNN and LF values. [1] Park and Park's (2012) study reveals, the increase of HF power parallels with a decrease in the LF/HF ratio during paced breathing at10 b/min as compared to spontaneous breathing. However, no significant difference between the two conditions observed when considering LF power. Further, the personality traits were measured using the Temperament and Character Inventory. [27] The pieces of evidence showed the cooperativeness in subjects showed an inverse correlation with HF power and self-transcendence contrariwise with both LF and HF power. [28]

The shreds of evidence have proven paced breathing associated with an increased subjective perception of relaxation. Van Diest et al., (2014) in his study observed that respiratory sinus arrhythmia RSA, higher LF, and lower HF power during 6 b/min paced breathing with different inspiration/expiration ratios. [29] Smith, 2001 has revealed, on a comparison of 12 b/min breathing with paced breathing at 6 b/min was characterized, at a subjective level, by higher positive energy, higher pleasantness, and lower arousal levels, which as measured with the Smith Relaxation States Survey. [30] A study by Stark et al. (2000) had differential views; in his study, he observed no clear association between cardio-respiratory parameters and psychological/ behavioral outcomes related to slow-paced breathing. Further. In Bradley and Lang, 1994 in their study analyzed, differences in emotional scores of the Self-Assessment Manikin Scale, among these different paced breathing frequencies. [31] The association between breathing control and the difference in HF and LF power, nevertheless, Kharya et al., (2014) viewed no difference in HF and LF power, and LF/HF ratios between slow breathing, fast breathing, and spontaneous breathing. Though on the psychological/behavioral side, an improvement in the lifestyle Management Scale revealed a slow breathing group as compared to others. [32]

Breathe control neurophysiological effect and behavioral outcomes:

Breathing technics are useful in improving sleep. The literature study has proven that voluntary abdominal breathing significantly reduces the alpha peak, and the rise in alpha activity in the parietal areas of the brain is observable in the EEG. [33] One of the literature studies reports the berthing technique is successful in improving vigor-activity in the profile of mood states and reduced anxiety. [34] Moreover, shreds of evidence have also reported reduced scores in tension-anxiety, depression-dejection, anger-hostility, and confusion on the profile of mood states. [35] During paced breathing is has demonstrated decreased EEG theta power on left frontal, right temporal and left parietal areas, and increased alpha power over the whole cortex. [27] Evidential changes analyzed in the previous literature studies on electroencephalogram (EEG) and heart rate variability (HRV) parameters during paced breathing (PB), their relationships with self-reported personality traits. [27]

One of the previous studies has proven using the Temperament and Character Inventory subscales that measure personality traits such as harm avoidance, innovation, persistence, self-directedness, and self-transcendence were positively correlated with EEG alpha power. [36] In an fMRI study, found increased Blood Oxygenation Level Dependent (BOLD) activity in a large number of brain areas during paced breathing such as sub-cortical structures include the dorsal length of the pons, thalamic regions, cerebellum, striatum, sub-parabrachial nucleus parabrachial nuclei, locus coeruleus, periaqueductal gray, hypothalamus, and hippocampus. Here the areas of the brain motor, supplementary motor and parietal cortices activated. [36]

The previous studies have proven the correlation between brain activity and Heart rate variability (HRV); there is also evidences demonstrating a positive correlation between HRV and activations of the medulla and hippocampus. [37] The anterior insula, dorsomedial prefrontal cortex, and left occipital cortex are negatively correlated. The evidence found EEG alpha power changes associated with pace berating and mood. [37] The self-assessment using the two-dimensional mood scale is used for assessing mood changes associated with slow breathing. [38]

Classical views east and western views on breathing techniques:

The term meditation understood with the technique it uses. The definition by Johnson, “meditation is the wide range of activities that seek to expand and emphasize the mind's reach and its possible functioning, achieved mostly by methods of sensory-motor discipline, which include remaining seated in silence, relaxing, closing one's eyes, breathing consciously and adopting an object of consciousness” [39] The review explores the literature witnesses meditation is the first and foremost a technique, a way of developing consciousness. [40]

During meditation, mental activity is naturally installed by narrowing down attention to the focused field and is maintained. Literature studies have proven that meditation produces a specific pattern of physiological responses through various biological systems. In the east, the frequently practiced mechanisms are meditation, which produces beneficial outcomes in autonomic, endocrine, neurological, cardiovascular, and psychological metabolism [41]. Transcendental meditation introduced in the west by Indian Mahesh Yogi, which become popular in the 1960s, and in the 1970s. The scientific research on meditation practice with its caused physiological effects presented for the first time during this period. [42] This practice defined as a simple and natural method that establishes a peaceful and deep rest also full mental awareness. [43] This concept later described in western psychology as three states of consciousness that include sleep, dream, and wakefulness. Nonetheless, in eastern philosophy, another state is considered is known as the fourth state of consciousness achieved through the practice of meditation. [44]

The meditation aimed at narrowing attention by eliminating unwanted thought processes and reduces the internal dialogue of the mind, which increases the state of higher consciousness and a great sense of physical and mental calmness. [45] The literature pieces of evidence that the practitioners of transcendental meditation affirm, they do not follow any specific religious practice. Their practices emphasize only the spiritual dimension of a specific technique. [46] The evidence of the previous study reveals the analyzed concepts of spirituality in research on the area of health. [47] The scientific views about what spirituality reveals the notions of transcendence and a sense of connection centers with an understanding of spirituality in this field of study. [48] Transcendence is an experience outside the material existence of everyday life, and connectedness, which is the perception of being connected to people, nature, and the cosmos. Here one is able to have an intrapersonal, interpersonal, and transpersonal connection. Transcendental meditation is an example of research on spiritual meditation, then that of meditation techniques based on an earthly understanding. [49]

Literature has revealed scientific facts on the examined meditation techniques, beneficial effects were found more consistently after the use of TM, which is a practice spiritually substantiated, than in individuals who used techniques of secular meditation or relaxation [50]. Pieces of evidence in the literature have revealed the positive effects reported after the practice of transcendence meditation is wide and include reducing anxiety, [51] increase self-accomplishment [52], increased creativity and concentration [52], increase in autonomic stability [53], a significant decrease of cortisol and norepinephrine plasma levels, increased serotonin and dopamine , blood pressure control [54], among others.

Cognitive/behavioral aspects in breath control techniques:

The breath control and paced breathing is associated with cognitive and behavioral aspects, practice slow abdomen breathing seen in transcendental meditation has proven positive influence on the improvement of cognitive functions in attention. [55] The deep breathing practice or meditation has a direct influence on the increase of cerebral perfusion in the prefrontal, parietal and auditory cortex regions, observed by a protective effect on the thickness of the gray mass. [56,57]

The current research analysis also observes the literature fact that the greater stimulation in the areas involved with attention, which had to increase the strength of cognitive circuits. [58,59] Breathe control practices is proven its efficacy in the process of myelination or restructuring of the white matter, associated with the anterior cingulate cortex. It is also observed evidencing facts on neuroprotection, that decrease in the synthesis and release of cortisol, which reduces stress, which is associated with the volume of the hippocampus region, these changes are also seen in meditation practitioners. [60] Relaxation using musical and textual memory activates the amygdala and hippocampus, possibly resulting in better memory consolidation and learning. [61,62] There is great heterogeneity in the classical breath control technique and the current behavioral techniques breath control. These techniques can have different effects on the brain that affect

The analysis of current review records checked is the contribution of slow breathing techniques, records related to clinical outcomes of chronic and acute pathologies excluded in this review study. The reviews in the literature that come across the study were focusing on investigating the effects of interventions that are characterized by a combination of breathing techniques, postures, and meditation. Also, investigations include exploring the effects of emotional stimulation while performing a specific breathing technique. The paced breathing used with other kinds of interventions or used during active stimulation emotions of the subjects such as anger, stress, and so on. These studies were quite interesting but excluded from the current review study, which did not express clear-cut identification of the specific psychophysiological effects of breath modulation. A number of studies were excluded, which focused on techniques without conscious regulation of breathing. All the studies related to voluntary breath control with psychophysiological effect on behavioral outcome were included in this study.

CONCLUSIONS:

This review literature study on the psychophysiological effects of breath control practices of both east and west hat identifies the effectiveness of physiological mediators impacting psychological and behavioral benefits. The breathing technique helps in anxiety management base on psycho-physiological correlates, which also leads to positive behavioral and physical outcome such as increased comfort, relaxation, pleasantness, vigor and alertness, and reduced symptoms of arousal, anxiety, depression, anger, and confusion. Slow breathing techniques act enhancing autonomic, cerebral and psychological flexibility. Additionally, the central nervous system increases the EEG alpha control and decreases EEG theta control associated with emotional and psychological well-being in healthy people. The psychophysiological changes by slow breathing voluntarily regulate the sense of the internal state of the body and a sense organ or cell that responds to mechanical stimuli within the nasal vault in translating slow breathing in the modulation of olfactory bulb activity, which tunes the activity of the entire cortical mantle. The review study authenticates the psychophysiological aspect with breath control. The implications of the study have better insight into the benefits of breath control, which would motivate people to practice voluntary breath control techniques and also using these techniques in mental health areas as part of their intervention.

CONFLICT OF INTEREST STATEMENT:

There is no conflict of interest between the authors.

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Received on 11.08.2020 Modified on 24.08.2020

Research J. Pharm. and Tech. 2020; 13(10):5012-5017.

DOI: 10.5958/0974-360X.2020.00878.1