Device-guided breathing in the home setting: Technology, performance and clinical outcomes

Usability, acceptance, and the role of realism in virtual humans for breathing exercise training

Breathing exercises are used to address a multitude of issues ranging from mental health to physical well-being. While they are recommended for various health conditions, access to professional support is often limited due to time and cost constraints. Virtual Reality technology offers a promising solution for enhancing mindfulness and relaxation practices, including breathing exercises. In our study, we explored the effectiveness of a computer-generated "virtual breathing coach". Our virtual coach has a human appearance, speaks in a human voice, and displays breathing physiology while guiding the participants through a set of breathing exercises of different cycle lengths. The agent exhibits breathing behaviour with the aim of augmenting the influence the agent exerts through the mechanisms of physiological entrainment known from human-to-human interaction. Our empirical, exploratory study with 20 participants, was conducted using non-immersive VR where the system ran on a web browser. On the one hand, we investigated the perception of the virtual human coach, and on the other hand, we evaluated the usability, acceptability, and adherence of the system. We also evaluated the role of realism in acceptance of and adherence to the virtual coach. Participants' responses were recorded using questionnaires. Participants were influenced by the virtual coach and adhered to it if they perceived the virtual coach as more realistic. The participants reported that the system ran well, and they would be willing to continue using the system in the future. Although the virtual human-to-human interaction experience provided by our system is not on par with the naturalistic human-to-human interaction, the results indicate that people are willing to replace a real human coach with a virtual coach. Systems like this are a step towards improving the affordability and on-demand access to another human, such as a coach in our system, especially where access and affordability are limited such as in healthcare. The qualities such as trust and likeability in an embodied interaction can make this interaction more efficient and effective.

Existing Meditation and Breathing Devices for Stress Reduction and Their Incorporated Stimuli: A Systematic Literature Review and Competition Analysis

To identify, evaluate, and summarize existing meditation and breathing devices for stress reduction and their characteristics (stimuli), we searched PubMed and EMBASE for studies published from January 1, 1980, to December 30, 2021. Full-text articles that presented devices that support meditation and breathing guidance for stress reduction were included. We excluded articles covering study protocols. In addition, a competitor analysis was conducted to identify and evaluate the devices, their name, manufacturer, target group, function, and incorporated stimuli were contracted. The scientific literature identified 367 studies, of which 20 (describing 18 devices and 32 stimuli) were included. The competition analysis identified 66 devices incorporating 126 stimuli. After exclusion of duplicates, this resulted in 46 different types of devices incorporating 24 different types of stimuli. They were organized into 7 device categories (attachable to the head, huggable devices, handheld devices, eye masks, mouth-controlled devices, toys, and wearables) and 14 stimuli categories (perceptible vibrations, imperceptible vibrations, movement, temperature, pressure, texture, light or darkness, abstract visuals, concrete visuals, music, calming sounds, tones, voice guidance, and aromas). This review provides an overview of the different meditation and breathing devices for stress reduction. The current overview will inform a subsequent preference and effectiveness study of breathing devices that aims to gain more knowledge on the topic to increase device uptake and developmental success.

Breathing exercise for hypertensive patients: A scoping review

Background: Non-pharmacological management of hypertension includes weight loss, alcohol and sodium restriction, regular exercise, and relaxation. In people with overweight hypertension, systolic blood pressure (SBP) and diastolic blood pressure (DBP) can be decreased via exercise and weight loss together. Breathing exercises are one method of relaxing. Objectives: The aim of this scoping review is to map the information that is currently available about the advantages of breathing exercises in decreasing blood pressure in hypertension patients. Methods: This scoping review adheres to Arksey and O'Malley's framework, which entails identifying review questions, seeking pertinent evidence, choosing pertinent studies, mapping data, and discussing, concluding, and reporting the findings. The PRISMA flowchart is used to show how the evidence search process works. Results: As a result, 339 articles in total were retrieved from the three databases. 20 papers total were included in this review after screening. In 14 of the 20 investigations, participants with stage 1 and stage 2 essential hypertension, two with pre-hypertension, and four with Isolated Systolic Hypertension (ISH) were studied. The respondents' ages ranged from 18 to 75. The systolic blood pressure declined by 4-54.22 mmHg, while the diastolic blood pressure dropped by 3-17 mmHg. Conclusion: Slow breathing can be used as an alternate, non-pharmacological therapy for hypertension individuals to reduce blood pressure. Systematic Review Registration: (https://osf.io/ta9u6/).

Reducing Test Anxiety by Device-Guided Breathing: A Pilot Study

Test anxiety remains a challenge for students and has considerable physiological and psychological impacts. The routine practice of slow, Device-Guided Breathing (DGB) is a major component of behavioral treatments for anxiety conditions. This paper addresses the effectiveness of using DGB as a self-treatment clinical tool for test anxiety reduction. This pilot study sample included 21 healthy men and women, all college students, between the ages of 20 and 30. Participants were randomly assigned to two groups: DGB practice (n = 10) and wait-list control (n = 11). At the beginning and the end of 3-weeks DGB training, participants underwent a stress test, followed by measures of blood pressure and reported anxiety. Anxiety reduction in the DGB group as compared to controls was not statistically significant, but showed a large effect size. Accordingly, the clinical outcomes suggested that daily practice of DGB may lead to reduced anxiety. We assume that such reduction may lead to improved test performance. Our results suggest an alternative treatment for test anxiety that may also be relevant for general anxiety, which is likely to increase due to the ongoing COVID-19 pandemic.

Respiratory rate modulation improves symptoms in patients with pulmonary hypertension

Background:

Pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension are chronic diseases with a severe symptom burden. Common symptoms are dyspnoea at light activity and general fatigue that limits daily activities. Respiratory modulation by device-guided breathing decreased symptoms in patients with heart failure. The aim of this pilot study was to investigate if respiratory modulation could improve symptoms of dyspnoea in patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension.

Method:

Adult patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension with symptoms of dyspnoea at rest or light activity performed home-based respiratory modulation by device-guided breathing 20 min a day for 3 months. Patients were on stable disease-specific treatment ⩾3 months and willing to undergo all study procedures. Dyspnoea score, World Health Organization class, physical status, N-terminal pro b-type natriuretic peptide, quality of life, respiratory rate and 6-min walk distance were assessed before and after 3 months with respiratory modulation.

Results:

Nine patients with pulmonary arterial hypertension and five with chronic thromboembolic pulmonary hypertension completed the study protocol. Mean age was 71 ± 14 years, and 11 were women. After 3 months of respiratory modulation, dyspnoea score (−0.6, p = 0.014), respiratory rate at rest (−3 breaths/min, p = 0.013), World Health Organization class (−0.3, p = 0.040), quality of life (EuroQol Visual Analogue Scale +5 points, not significant) and decreased N-terminal pro b-type natriuretic peptide (−163 ng/L, p = 0.043) had improved. The fatigue and respiratory rate after the 6-min walk decreased while the 6-min walk distance remained unchanged.

Conclusion:

Patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension that used device-guided breathing for 3 months improved symptoms of dyspnoea and lowered the respiratory rate at rest and after exercise.

The effect of pursed-lip breathing combined with number counting on blood pressure and heart rate in hypertensive urgency patients: A randomized controlled trial

Hypertensive urgency (HT urgency) is an alarming sign of uncontrolled hypertension. It is aggravated by nonadherence to medication, as well as psychosocial stress. Mindfulness is beneficial for reducing stress, while deep and slow breathing is effective for lowering blood pressure (BP). In our study, we aimed to assess BP and heart rate effects in HT urgency patients practicing pursed‐lip breathing and number counting (PLB with NC)—a practice that promotes mindfulness with deep/slow breathing patterns. In a randomized controlled trial, 110 patients were equally allocated to intervention and control groups. The intervention group was trained and encouraged to do PLB with NC during their emergency room admission, while the control group received conventional medical care. The mean systolic BP (SBP), diastolic BP (DBP), and HR of the intervention group in the 3rd hour were significantly lower than the baseline values at −28.2 mm Hg (95%CI;‐23.5 to −32.4), −17.1 mm Hg (95%CI;‐14.2 to −20.0), and −4.9 beats per minute (bpm) (95%CI;‐4.0 to −5.8), respectively. In the control group, both the mean SBP and DBP were also significantly lower in the 3rd hour. However, HR reduction was inconclusive. When the two groups were compared, a greater degree of reduction was found in the intervention group for SBP (9.80 mm Hg, 95%CI; 4.10 to 15.50), DBP (7.69 mm Hg, 95%CI; 3.61 to 11.77), and HR (3.85 bpm, 95%CI; 1.99 to 5.72). In conclusion, PLB with NC was effective for lowering BP and HR. It might be used as a complementary treatment for HT urgency patients.

When Agents Become Partners: A Review of the Role the Implicit Plays in the Interaction with Artificial Social Agents

The way we interact with computers has significantly changed over recent decades. However, interaction with computers still falls behind human to human interaction in terms of seamlessness, effortlessness, and satisfaction. We argue that simultaneously using verbal, nonverbal, explicit, implicit, intentional, and unintentional communication channels addresses these three aspects of the interaction process. To better understand what has been done in the field of Human Computer Interaction (HCI) in terms of incorporating the type channels mentioned above, we reviewed the literature on implicit nonverbal interaction with a specific emphasis on the interaction between humans on the one side, and robot and virtual humans on the other side. These Artificial Social Agents (ASA) are increasingly used as advanced tools for solving not only physical but also social tasks. In the literature review, we identify domains of interaction between humans and artificial social agents that have shown exponential growth over the years. The review highlights the value of incorporating implicit interaction capabilities in Human Agent Interaction (HAI) which we believe will lead to satisfying human and artificial social agent team performance. We conclude the article by presenting a case study of a system that harnesses subtle nonverbal, implicit interaction to increase the state of relaxation in users. This “Virtual Human Breathing Relaxation System” works on the principle of physiological synchronisation between a human and a virtual, computer-generated human. The active entrainment concept behind the relaxation system is generic and can be applied to other human agent interaction domains of implicit physiology-based interaction.

The influence of mindfulness meditation on inattention and physiological markers of stress on students with learning disabilities and/or attention deficit hyperactivity disorder

BACKGROUND

Over recent decades, the number of students diagnosed with learning disabilities and/or attention deficit hyperactivity disorders has substantially increased. These students face various challenges and experience stress when receiving higher education.

AIMS

The purpose of this study was to compare two non-pharmacological interventions: mindfulness and device-guided slow breathing, with a control group.

METHODS

Seventy-three students (age = 25.76, std. dev = 3.10) with attention problems and/or learning disabilities were randomly assigned to three groups: mindfulness meditation, device guided breathing practice and waiting-list control. Before and after the intervention physiological and psychological measures were collected.

RESULTS

Our results show that only mindfulness practice improved awareness of the present moment and decreased hyperactivity and inattention. Furthermore, both mindfulness and practice with device-guided breathing were associated with stress reduction, as shown by an increase in the galvanic skin response only in the control group.

CONCLUSIONS

Implementation of the study results may lead to an advance in treating attention deficit disorders and learning disabilities, especially among higher education students.

Development and application of a respiratory device on blood pressure in adults with high blood pressure

Purpose

The purpose of this study is to develop a prototype of a novel respiratory device that we validated and assessed clinically and examined the effect of prototype of respiratory device on blood pressure (BP).

Methods

Prototype of respiratory device (TU-Breath Training) was designed with pressure cuff and application software was created. The immediate effect of resisted breathing was determined in 20 adults with high BP (systolic BP ≥ 130 mmHg and diastolic BP ≥ 90 mmHg). A crossover study was designed. A total of 20 eligible participants were asked to sit quietly for 10 min. Heart rate (HR), BP, and oxygen saturation (SpO₂) were measured and recorded. After the resting period, all participants were randomized and counterbalanced for undergoing the set of inspiratory muscle training by TU-Breath Training and control group. A set of respiratory training were composed of 10 times per set for three sets, while the control group was asked to sit for 10 min.

Results

After inspiratory training, both the systolic and diastolic BP decreased significantly. Compared with control group, using TU-Breath Training decreased systolic BP (−7.00 ± 5.93 mmHg) and diastolic BP (−5.95 ± 8.88 mmHg), but did not show differences in HR and SpO₂.

Conclusion

The study indicated that in high-BP participants, the prototype of respiratory device (TU-Breath Training) elicits decreased BP.

The Influence of Auditory Cues on Bodily and Movement Perception

The sounds that result from our movement and that mark the outcome of our actions typically convey useful information concerning the state of our body and its movement, as well as providing pertinent information about the stimuli with which we are interacting. Here we review the rapidly growing literature investigating the influence of non-veridical auditory cues (i.e., inaccurate in terms of their context, timing, and/or spectral distribution) on multisensory body and action perception, and on motor behavior. Inaccurate auditory cues provide a unique opportunity to study cross-modal processes: the ability to detect the impact of each sense when they provide a slightly different message is greater. Additionally, given that similar cross-modal processes likely occur regardless of the accuracy or inaccuracy of sensory input, studying incongruent interactions are likely to also help us predict interactions between congruent inputs. The available research convincingly demonstrates that perceptions of the body, of movement, and of surface contact features (e.g., roughness) are influenced by the addition of non-veridical auditory cues. Moreover, auditory cues impact both motor behavior and emotional valence, the latter showing that sounds that are highly incongruent with the performed movement induce feelings of unpleasantness (perhaps associated with lower processing fluency). Such findings are relevant to the design of auditory cues associated with product interaction, and the use of auditory cues in sport performance and therapeutic situations given the impact on motor behavior.

Optimization of Vagal Stimulation Protocol Based on Spontaneous Breathing Rate

Controlled breathing maneuver is being widely applied for cardiovascular autonomic control evaluation and cardiac vagal activation through reduction of breathing rate (BR). However, this maneuver presented contradictory results depending on the protocol and the chosen BR. These variations may be related to the individual intrinsic profile baseline sympathetic tonus, as described before by others. In this study, we evaluated the effect of controlled breathing maneuver on cardiovascular autonomic control in 26 healthy subjects allocated into two protocols: (1) controlled breathing in three different rates (10, 15, and 20 breaths/min) and (2) controlled breathing in rates normalized by the individual spontaneous breathing rate (SBR) at 100, 80, 70, and 50%. Our results showed autonomic responses favorable to vagal modulation with the lower BR maneuvers. Nevertheless, while this activation was variable using the standard protocol, all participants of the normalized protocol demonstrated an increase of vagal modulation at 80% BR (HFnu 80 = 67.5% vs. 48.2%, p < 0.0001). These results suggest that controlled breathing protocols to induce vagal activation should consider the SBR, being limited to values moderately lower than the baseline.

The impact of breathing pattern and rate on inspiratory muscles activity

Different rehabilitation programs are used to relieve dyspnea for hyper-inflated lung patients. In this study, a new approach, based on integrated changes in respiratory rate and pattern, for inspiratory muscles rehabilitation and training was examined utilizing noninvasive measurements of the two inspiratory muscles (rib cage inspiratory and neck inspiratory muscles) activity during controlled breathing in healthy subjects. Muscles activity was measured using electromyography, while subjects, breathed at different combinations of respiratory rate (6, 10, 16 breath per minutes) and inspiratory duty cycles (TI/Ttot). The results clearly show that both muscles were most active at the lowest evaluated respiratory rate, and that alteration of the duty cycle at the lowest rate significantly (p< 0.05) changes their electrical activity. Breathing at low respiratory rate RR is recommended for hyper-inflated lung patients in order to improve their gas exchange, therefore, it is recommended for these patients to find their most effective combination of RR and TI/Ttot and to use control breathing to practice their breath at optimum combination.

An evidence-based stress management intervention for allogeneic hematopoietic stem cell transplant caregivers: development, feasibility and acceptability

PURPOSE

Caregivers of cancer patients face challenges impacting their physical, psychological and social well-being that need attention in the form of well-designed and tested interventions. We created an eight-session individual stress management intervention for caregivers of allogeneic hematopoietic stem cell transplant (Allo-HSCT) recipients. This intervention, tested by randomized control trial, proved effective in decreasing distress. Herein, we describe the intervention including theoretical framework, development, and elements of fidelity. Implementation challenges along with recommendations for refinement in future studies are discussed with the goal of replication and dissemination.

METHODS

Seventy-four of 148 caregivers received stress management training following randomization. The intervention occurred during the 100-day post-transplant period when caregivers are required. The training provided integrated cognitive behavioral strategies, psychoeducation, and problem-solving skills building as well as use of a biofeedback device.

RESULTS

Seventy percent of caregivers completed all eight sessions indicating good acceptability for the in-person intervention; however, most caregivers did not reliably use the biofeedback device. The most common reason for drop-out was their patient becoming gravely ill or patient death. Few caregivers dropped out because of study demands. The need for flexibility in providing intervention sessions was key to retention.

CONCLUSION

Our evidence-based stress management intervention for Allo-HSCT caregivers was feasible. Variability in acceptability and challenges in implementation are discussed and suggestions for refinement of the intervention are outlined. Dissemination efforts could improve by using alternative methods for providing caregiver support such as telephone or video chat to accommodate caregivers who are unable to attend in-person sessions.

The coupling between peripheral microcirculation and slow breathing

Vasomotion (rhythmic changes in arteriolar diameter) is believed to enhance tissue perfusion at low oxygenation levels. We hypothesized that slow breathing and vasomotion may correlate temporally ("coupling"), especially at low oxygenation levels. We paced down spontaneous breathing to about 5 or 6breaths/min in 14 healthy subjects using device-guided breathing (DGB), and continuously monitored respiration, transcutaneous oxygen pressure ("oxygenation"), and skin capillary blood flow ("microflow") using a laser Doppler flowmeter. The coupling was expressed by cross-correlation calculated in 1-min time windows. Our main results illustrated that: (1) coupling increased gradually upon slowing breathing down in a subgroup, in which initial oxygenation was lower than a threshold of 30mmHg (0.3±0.2 vs. 0.07±0.2, P<10^-6); (2) during DGB changes in oxygenation elicited opposite (relative) changes in microflow, with 4-fold higher sensitivity for low initial oxygenation relative to high (regression slope -0.094±0.010mmHg^-1 vs. -0.020±0.002mmHg^-1, P<10^-6); (3) at low initial oxygenation, we observed larger coupling and (relative) microflow changes in younger subjects, and greater oxygenation changes in females (P<10^-6 for all); (4) pulse pressure changes from before to after DGB were reduced by increased oxygenation changes during DGB (-5.5±7.4mmHg, r=-0.73, P<0.001). In conclusion, the present methodology can provide the variation trend of respiration-vasomotion coupling during DGB that may characterize microcirculation behavior at tissue oxygenation below a measurable threshold. The potential association of these trends and thresholds with pathologies or specific conditions of the cardiopulmonary system, and the possible role played by the neural sympathetic activity in that coupling, deserve further studies.

Blood pressure changes in patients with chronic heart failure undergoing slow breathing training

BACKGROUND

Slow breathing training (SBT) has been proposed as a new non-pharmacological treatment able to induce favorable effects in patients with chronic heart failure (CHF). However, no information is available regarding its effects on orthostatic blood pressure (BP) changes in these patients, an issue of practical relevance given the reported BP-lowering effect of SBT. The aim of this study is to evaluate the influence of SBT on BP and whether SBT induces orthostatic hypotension (OH) or changes in quality of life (QoL) in CHF patients.

METHODS

The analysis was performed as part of an ongoing crossover open trial aimed at assessing the clinical effectiveness of SBT in treated patients with CHF. The patients underwent 10-12 weeks of SBT with the RESPeRATE device and 10-12 week follow-up under usual care. Patients were randomly divided into two groups: group I began with SBT, followed by usual care; group II began with usual care, followed by SBT. Patients undergoing SBT were asked to perform each day two separate 15 min sessions of device-guided SBT at a breathing frequency of 6 breaths/min. In all patients, before the enrollment and after each study phase, clinical data collection and BP measurements in sitting, supine and standing position were performed. OH was defined as a decrease of ≥ 20 mmHg in systolic blood pressure (SBP) or ≥ 10 mmHg in diastolic blood pressure (DBP) within 3 min of standing. QoL was assessed three times at the beginning, and after each phase of the study by the Minnesota Living with Heart Failure (MLHF) questionnaire.

RESULTS

Forty patients (two equal groups) completed the study, with the following baseline characteristics: 32 males/eight females, age 63.3 ± 13.4 years, 25 with ischemic CHF, 37 in New York Heart Association class II and three in class III, left ventricular ejection fraction 30.8 ± 6.7%, mean BP 138.7 ± 16.5/83.1 ± 11.5 mmHg, 23 with arterial hypertension and four with a history of stroke. There were no significant differences between the groups in clinical characteristics, SBP and DBP at rest, while seated and before and after standing up. OH prevalence was low and did not change during the study (10% vs 10%). No significant difference in average SBP and DBP changes secondary to body position were found when comparing the two study phases. Decrease in MLHF score was observed in group I during SBT (p = 0.002), but not in group II.

CONCLUSIONS

Our data indicate that SBT is safe, does not affect the prevalence of OH in CHF patients and shows a non-significant tendency to improve QoL. These results should be confirmed in a larger sample of patients to support the safety of SBT and its possible benefits as a novel component of cardiorespiratory rehabilitation programs in CHF.

A randomized control trial of a psychosocial intervention for caregivers of allogeneic hematopoietic stem cell transplant patients: effects on distress

Caregivers of patients receiving allogeneic hematopoietic stem cell transplants (Allo-HSCT) serve a pivotal role in patient care but experience high stress, anxiety, and depression as a result. We theorized that a stress management adapted for Allo-HSCT caregivers would reduce distress compared to treatment as usual (TAU). From 267 consecutive caregivers of Allo-HSCT patients approached, 148 (mean=53.5 years, 75.7% female) were randomized to either psychosocial intervention (n=74) or TAU (n=74). Eight 1-on-1 stress management sessions delivered across the 100 day post-transplant period focused on understanding stress, changing role(s) as caregiver, cognitive behavioral stress management, pacing respiration, and identifying social support. Primary outcomes included perceived stress (psychological) and salivary cortisol awakening response (CAR) (physiological). Randomized groups were not statistically different at baseline. Mixed models analysis of covariance (intent-to-treat) showed that intervention was associated with significantly lower caregiver stress 3 months post-transplant (Mean=20.0, CI₉₅=17.9-22.0) compared to TAU (Mean=23.0, CI₉₅=21.0-25.0) with an effect size (ES) of 0.39 (p=0.039). Secondary psychological outcomes, including depression and anxiety, were significantly reduced with ESs of 0.46 and 0.66 respectively. Caregiver CAR did not differ from non-caregiving controls at baseline and was unchanged by intervention. Despite significant caregiving burden, this psychosocial intervention significantly mitigated distress in Allo-HSCT caregivers.

Effects of guided deep breathing on breathlessness and the breathing pattern in chronic obstructive pulmonary disease: a double-blind randomized control study

OBJECTIVE

To investigate whether guided deep breathing using a device improves breathlessness, quality of life, and breathing pattern in moderate and severe stage of chronic obstructive pulmonary disease (COPD).

METHODS

In total, 150 patients participated in a double-blind randomized controlled trial in a four-week intervention and a four-month follow-up. Participants were randomized into a guided deep breathing group (GDBG), music listening group (MLG), or sitting still group (SSG). The patients' symptom score using the St George's Respiratory Questionnaire (SGRQ), and a Global Rating Change scale (GRC) was applied to measure breathlessness as primary outcome. The activity score and impact score of SRGQ, and breathing pattern were secondary outcomes.

RESULTS

Positive effects of the GDBG were detected in GRC scale in breathlessness at four weeks (p=0.03) with remaining effect compared to MLG (p=0.04), but not to SSG at four months follow-up. GDBG showed positive effect for respiratory rate (p<0.001) at four weeks follow-up. A positive significant change (p<0.05-0.01) was found in all groups of SGRQ symptom score.

CONCLUSION

GDBG had a beneficial effect on respiratory pattern and breathlessness. MLG and SSG also yielded significant improvements.

PRACTICE IMPLICATIONS

Guided deep breathing may be used as a self-management procedure.

"Anatomy of an Illness": control from a caregiver's perspective

Caregivers of loved ones with chronic illnesses experience an uncontrollable challenge with potentially negative behavioral and medical consequences. Extensive research has demonstrated immune and endocrine regulation can be significantly disrupted by negative behavioral factors based on both animal models and human studies. However, fewer studies have focused on how psychosocial interventions might reverse the negative consequences of stressors such as caregiving. The distress of caring for individuals with cancer has only recently begun to receive attention. These interventions addressing caregiver distress are rare overall and caregivers of patients receiving hematopoietic stem cell transplants (HSCT) have received even less attention. HSCT caregivers report feelings of loss of control. Animal studies suggest that control over aversive events can mitigate the negative consequences of stressors. Caregivers of allogeneic HSCT patients for blood cancers must be available 24/7 for three months or longer following stem cell infusion to closely monitor the recipients' health and well-being. Does establishing a greater sense of control have positive impacts on caregivers? A randomized control trial of a cognitive behavioral stress management intervention for allogeneic HSCT caregivers is briefly described. A model of caregiver mental health which may potentially impact the patient's quality of life is proposed. These relationships exist in a complex system that includes genetic influences, sex, social environment, and prior experience. This system fits well within recent formulations of a "complexity science" approach to health and well-being.

Beyond medications and diet: alternative approaches to lowering blood pressure: a scientific statement from the american heart association

Many antihypertensive medications and lifestyle changes are proven to reduce blood pressure. Over the past few decades, numerous additional modalities have been evaluated in regard to their potential blood pressure-lowering abilities. However, these nondietary, nondrug treatments, collectively called alternative approaches, have generally undergone fewer and less rigorous trials. This American Heart Association scientific statement aims to summarize the blood pressure-lowering efficacy of several alternative approaches and to provide a class of recommendation for their implementation in clinical practice based on the available level of evidence from the published literature. Among behavioral therapies, Transcendental Meditation (Class IIB, Level of Evidence B), other meditation techniques (Class III, Level of Evidence C), yoga (Class III, Level of Evidence C), other relaxation therapies (Class III, Level of Evidence B), and biofeedback approaches (Class IIB, Level of Evidence B) generally had modest, mixed, or no consistent evidence demonstrating their efficacy. Between the noninvasive procedures and devices evaluated, device-guided breathing (Class IIA, Level of Evidence B) had greater support than acupuncture (Class III, Level of Evidence B). Exercise-based regimens, including aerobic (Class I, Level of Evidence A), dynamic resistance (Class IIA, Level of Evidence B), and isometric handgrip (Class IIB, Level of Evidence C) modalities, had relatively stronger supporting evidence. It is the consensus of the writing group that it is reasonable for all individuals with blood pressure levels >120/80 mm Hg to consider trials of alternative approaches as adjuvant methods to help lower blood pressure when clinically appropriate. A suggested management algorithm is provided, along with recommendations for prioritizing the use of the individual approaches in clinical practice based on their level of evidence for blood pressure lowering, risk-to-benefit ratio, potential ancillary health benefits, and practicality in a real-world setting. Finally, recommendations for future research priorities are outlined.

Breathing practices for treatment of psychiatric and stress-related medical conditions

Neurophysiological studies may explain how breathing techniques normalize stress response, emotion regulation, and autonomic and neuroendocrine system function. Breath practices have been shown to reduce symptoms of stress, anxiety, insomnia, post-traumatic stress disorder, mass disasters, depression, and attention deficit disorder. Technology-assisted breathing interventions facilitate therapeutic breathing by using either static cues such as a breath pacer or real-time feedback based on physiological parameters such as heart rate variability. The empirical literature indicates that technology-assisted breathing can be beneficial in mental health treatment, though it may not be appropriate for all individuals. Initial in-person training and evaluation can improve results.

How Does Heart Rate Variability Biofeedback Work? Resonance, the Baroreflex, and Other Mechanisms

Heart rate variability biofeedback is known to have multiple effects on the cardiovascular system, the respiratory system, and emotional reactivity. This paper reviews the origins of work on heart rate variability biofeedback, and mechanisms for its various effects, including direct effects on the baroreflex system and gas exchange efficiency, as well as indirect effects on emotional reactivity and possibly inflammatory activity. Resonance in the cardiovascular system is explained, as well as ways that heart rate variability biofeedback stimulates these resonance effects, through interactions between respiratory sinus arrhythmia and the baroreflex system. Relationships of these mechanisms to various clinical applications of heart rate variability biofeedback are explored, as are future extensions of biofeedback to the vascular tone baroreflex.

Imposing respiratory variability patterns

To ensure respiratory stability and flexibility, healthy breathing shows balanced variability consisting of considerable correlated variability (parameters of each breath are correlated to parameters of adjoining breaths) and some random variability. Sighing resets this balance when respiration lacks variability or becomes excessively irregular. The present study aimed to investigate the effect of imposed patterns of breathing variability on sighing and self-reported (dis)comfort. Spontaneous breathing was compared to imposed non-variable, correlated and random breathing. Results show that executing imposed breathing is difficult, demanding, and induces tension. Sigh occurrence following spontaneous and imposed breathing patterns could be predicted by self-reported discomfort and increased random variability. However, including non-variable, correlated and random breathing patterns only, the effects of self-reported discomfort on sigh occurrence override the effects of altered breathing variability.

Respiratory variability and sighing: a psychophysiological reset model

Whereas respiratory psychophysiological research has mainly studied respiratory time and volume, variability in these parameters has been largely disregarded, even though it may provide important information about respiratory regulation. The present paper reviews the literature on respiratory variability and elaborates on the importance of assessing various components of respiratory variability when studying the interrelationships between emotions and breathing. A model is proposed that predicts specific action tendencies related to emotions to disturb the balance between various respiratory variability components depending on valence by arousal and control dimensions. The central focus of the paper is sighing. The causes and consequences of sighing are reviewed and integrated in the proposed model in which sighing is hypothesized to function as a resetter in the regulation of both breathing and emotions, because it restores a balance in respiratory variability fractions and causes relief.

Low latency breathing frequency detection and monitoring on a personal computer

We demonstrate a low latency respiratory/breathing frequency detection system that is fast (<5 ms), easy to operate, requires no batteries or external power supply and operates fully via computer-standard USB connection. Exercises in controlling ones breathing frequency, usually referred to as paced-breathing exercises, have shown positive effects in treating pulmonary diseases, cardiovascular diseases and stress/anxiety-related disorders. We developed a breathing frequency detection system which uses two pairs of microphones to detect exhalation activity, eliminate noise from the environment and stream the recording data via USB connection to a personal computer. It showed 97.1% reliability (10 subjects) when monitoring breathing activity in non-guided free breathing and 100% reliability (10 subjects) when monitoring breathing activity during interactive paced-breathing exercises. We also evaluated the breathing frequency detection systems noise elimination functionality which showed a reduction of 84.2 dB for stationary (white noise) and a reduction of 79.3 dB for non-stationary (hands clapping) noise.