Biofeedback Condition Research Articles

Respiratory Biofeedback Does Not Facilitate Lowering Arousal in Meditation Through Virtual Reality

The current study examined the effectiveness of respiratory biofeedback in lowering subjective and objective arousal after stress. Participants were presented with a meditation session in virtual reality while subjective and objective arousal were measured, the latter measured through ECG and EEG. Three conditions were used: (a) a respiratory biofeedback condition, in which visual feedback was paired to breathing; (b) a control feedback placebo condition, in which visual feedback was not paired to breathing; and (c) a control no-feedback condition, in which no visual feedback was used. Subjective and objective arousal decreased during meditation after stress in all conditions, demonstrating recovery after stress during meditation in virtual reality. However, the reduction in arousal (on all outcome measures combined and heart rate specifically) was largest in the control feedback placebo condition, in which no biofeedback was used, indicating that respiratory biofeedback had no additional value in reducing arousal. The findings of the current study highlight the importance of including a control feedback placebo condition in order to establish the exact additional value of biofeedback and offer insights in applying cost-effective virtual reality meditation training.

Immediate effects of real-time postural biofeedback on spinal posture, muscle activity, and perceived pain severity in adults with neck pain

BackgroundPrevious studies have investigated various types of postural biofeedback devices on different body regions to improve posture; however, they focused only on healthy adults without a history of chronic musculoskeletal disorders. In addition, those postural biofeedback devices used in previous studies are often designed for experimental research. The designs are usually bulky with many wires, which is not practical for everyday use. Research questionThe aim of this study was to determine the immediate effect of a commercially available real-time postural biofeedback device on spinal posture, muscle activity, and perceived pain severity in adults with neck pain. Methods21 adults who had chronic or recurrent nonspecific neck pain for more than 3 months and whose pain was induced or aggravated by prolonged computer work were enrolled in this study. Spinal posture (head tilt, neck flexion, cervical and thoracic angles), muscle activity (cervical erector spinae, upper trapezius, and thoracic erector spinae), and self-reported neck and shoulder pain were measured during computer typing tasks, with and without biofeedback. ResultsCompared with the non-biofeedback condition, the biofeedback condition significantly decreased neck flexion, upper cervical, and lower thoracic angles and lowered the activity of the cervical erector spinae. Self-reported neck pain was not influenced by the application of biofeedback, but significantly increased over the 1-hour typing task. SignificanceThe application of a commercially available wearable real-time biofeedback device improves sitting posture and reduces muscular activity in adults with nonspecific neck pain during computer work. Future studies should examine the long-term effects of wearable real-time postural biofeedback devices for prevention and management of neck pain.

Heart-rate sonification biofeedback for poker

Abstract In this paper we show that heart-rate based audio/sonification biofeedback (HRSB) can be used to facilitate emotion regulation during poker play. We report on a laboratory experiment (N= 29) where participants play No Limit Texas Hold’em poker while hearing heartbeats synchronized with their actual heart-rate (biofeedback condition) or at steady pace (control condition). The synchronized heart-rate biofeedback decreased emotional reactivity in terms of arousal (as measured by skin conductance) and valence (as measured by facial electromyography). We also observed individual differences between participants in the effectiveness of the HRSB. The participants were profiled using the behavioural inhibition/activation system (BIS/BAS) questionnaires, and there was a significant correlation between the effectiveness of the biofeedback method and BIS/BAS scores; with biofeedback being effective primarily for participants with high BIS/BAS scores.

Comparative Effects of Auditory Electromyographic Biofeedback for Participants Who Are Blind and Sighted.

This study examined differences in auditory electromyographic biofeedback (AEB) effects between participants who were sighted and blind. Past research makes clear that AEB is effective for people who are blind, particularly because of their reported superiority in auditory processing, but no study has directly compared AEB efficacy between participants who are sighted and blind. A total of 11 participants who were sighted and 10 who were blind performed a motor task requiring 20 nonfatiguing muscle contractions at 20% maximal voluntary contraction (MVC) with or without AEB. AEB reduced the error (calculated as the absolute difference of two consecutive contractions) among both participant groups, and the error for the group without biofeedback was greater for the participants who were blind than that for the sighted participants (5.20% ± 2.05% MVC and 3.30% ± 1.26% MVC, respectively; p < .05). This finding was consistent with subjective rating data, also indicating a trend toward greater difficulty for participants who were blind when performing without biofeedback. Moreover, the AEB/no biofeedback condition showed fewer errors for the participants who were blind than for the participants who were sighted during the last part of the task ( p = .036), indicating that participants who were blind were better at maintaining the AEB effect. These data suggest that the poor motor performance of participants who were blind was greatly improved with AEB, suggesting important applications of AEB for assistive technologies, adapted sports, and activities of daily living.

Heart Rate Variability Biofeedback Does Not Substitute for Asthma Steroid Controller Medication.

Despite previous findings of therapeutic effects for heart rate variability biofeedback (HRVB) on asthma, it is not known whether HRVB can substitute either for controller or rescue medication, or whether it affects airway inflammation. Sixty-eight paid volunteer steroid naïve study participants with mild or moderate asthma were given 3months of HRVB or a comparison condition consisting of EEG alpha biofeedback with relaxing music and relaxed paced breathing (EEG+), in a two-center trial. All participants received a month of intensive asthma education prior to randomization. Both treatment conditions produced similar significant improvements on the methacholine challenge test (MCT), asthma symptoms, and asthma quality of life (AQOL). MCT effects were of similar size to those of enhanced placebo procedures reported elsewhere, and were 65% of those of a course of a high-potency inhaled steroid budesonide given to a sub-group of participants following biofeedback training. Exhaled nitric oxide decreased significantly only in the HRVB group, 81% of the budesonide effect, but with no significant differences between groups. Participants reported becoming more relaxed during practice of both techniques. Administration of albuterol after biofeedback sessions produced a large improvement in pulmonary function test results, indicating that neither treatment normalized pulmonary function as a potent controller medication would have done. Impulse oscillometry showed increased upper airway (vocal cord) resistance during biofeedback periods in both groups. These data suggest that HRVB should not be considered an alternative to asthma controller medications (e.g., inhaled steroids), although both biofeedback conditions produced some beneficial effects, warranting further research, and suggesting potential complementary effects. Various hypotheses are presented to explain why HRVB effects on asthma appeared smaller in this study than in earlier studies. Clinical Trial Registration NCT02766374.

Impact of Visual Feedback on Exercise Intensity and Motivation

PURPOSE: Determine if visual feedback motivates college-aged students to maintain a higher exercise intensity during an indoor cycling class and to ascertain the favored type of visual feedback. METHODS: Thirty participants took part in a within-subject design experiment. Participants were assigned a heart rate monitor and identification number to record and monitor exercise intensity during each class session. Participants completed three cycling classes that were randomly assigned as a no visual feedback (NF), individual feedback (IF), or group feedback condition (GF). A Spielberger Trait Anxiety survey was completed before the first session and the Spielberger State Anxiety survey was completed before every cycling session. For each condition, participants stated if they enjoyed the heart rate feedback received and using the heart rate monitors. At the end of the study, participants specified the visual biofeedback condition they preferred. RESULTS: The group feedback condition spent a higher percentage of time above 80% of their age-predicted heart rate maximum. Participants spent 17.5% of their time in the 80-90% heart rate zone and 2.8% in the 90-100% zone. No feedback and individual feedback groups spent 13.2% and 15.1% in the 80-90% heart rate zone and 0.9% and 2.7% in the 90-100% zone. A 1-way repeated measures ANOVA indicated a statistically significant difference between the time spent in the 60-70% heart rate zone between the three conditions. The group feedback condition had the highest average heart rate (138.1 bpm), maximal heart rate (174.4 bpm), and heart rate predicted caloric expenditure (293.5 kcal). A positive correlation was found between the group feedback RPE and enjoyment of group feedback (r=0.55, p=0.01). The RPE of individual feedback was positively correlated with working harder due to wearing a heart rate monitor (r=0.54, p=0.01) and receiving individual feedback (r=0.57, p=0.01). Twenty-one (70%) participants preferred group feedback, 4 participants (13.3%) favored the individual feedback, 1 participant (3.3%) chose no feedback, and 4 participants (13.3%) had no preference. CONCLUSIONS: Participants favored group feedback over individual feedback and no feedback. Visual feedback was associated with higher exercise intensity and greater enjoyment of the exercise session.

Breathing changes accompanying balance improvement during biofeedback

The aim of this study was to determine whether respiration would be altered during visual biofeedback condition while standing on a foam surface. Fifty young, healthy subjects (24 men, 26 women) were divided into a spirometry group, in which additional spirometry analysis was performed, and a control group. All subjects were tested in two conditions: 1) standing on a foam surface and 2) standing on a foam surface with visual biofeedback (VF) based on the centre of pressure (CoP). CoP amplitude and velocity in anterior-posterior (Aap, Vap) and medial-lateral (Aml, Vml) directions were measured by the force platform. Breathing movements were recorded by two pairs of 3D accelerometers attached on the upper chest (upper chest breathing – UCB) and the lower chest (lower chest breathing – LCB). Results showed that significant decreases of CoP amplitude and velocity in both directions were accompanied by a significant decrease of lower chest breathing, and an increase of LCB frequency was seen during VF condition compared to control condition in both groups. Moreover, a significant decrease in tidal volume and increased breathing frequency during VF condition were confirmed by spirometric analysis. Reduced breathing movements and volumes as well as increased breathing frequency are probably part of an involuntary strategy activated to maximize balance improvement during VF condition.

Adolescent development of insula-dependent interoceptive regulation.

Adolescence is hypothesized to be a critical period for the maturation of self-regulatory capacities, including those that depend on interoceptive sensitivity, but the neural basis of interoceptive regulation in adolescence is unknown. We used functional magnetic resonance imaging and psychophysiology to study interoceptive regulation in healthy adolescent females. Participants regulated their gut activities in response to a virtual roller coaster by deep breathing aided by visually monitoring their online electrogastrogram (EGG) activity through a virtual thermometer (i.e. gut biofeedback), or without biofeedback. Analyses focused on the insula, given its putative role in interoception. The bilateral posterior insula showed increased activation in the no-biofeedback compared to biofeedback condition, suggesting that the participants relied more on interoceptive input when exteroceptive feedback was unavailable. The bilateral dorsal anterior insula showed activation linearly associated with age during both induction and regulation, and its activation during regulation correlated positively with change of EGG in the tachygastria frequency band from induction to regulation. Induction-related activation in the bilateral ventral anterior insula was nonlinearly associated with age and peaked at mid-adolescence. These results implicate different developmental trajectories of distinct sub-regions of the insula in interoceptive processes, with implications for competing neurobiological theories of female adolescent development.

Variations in task constraints shape emergent performance outcomes and complexity levels in balancing.

This study investigated the extent to which specific interacting constraints of performance might increase or decrease the emergent complexity in a movement system, and whether this could affect the relationship between observed movement variability and the central nervous system's capacity to adapt to perturbations during balancing. Fifty-two healthy volunteers performed eight trials where different performance constraints were manipulated: task difficulty (three levels) and visual biofeedback conditions (with and without the center of pressure (COP) displacement and a target displayed). Balance performance was assessed using COP-based measures: mean velocity magnitude (MVM) and bivariate variable error (BVE). To assess the complexity of COP, fuzzy entropy (FE) and detrended fluctuation analysis (DFA) were computed. ANOVAs showed that MVM and BVE increased when task difficulty increased. During biofeedback conditions, individuals showed higher MVM but lower BVE at the easiest level of task difficulty. Overall, higher FE and lower DFA values were observed when biofeedback was available. On the other hand, FE reduced and DFA increased as difficulty level increased, in the presence of biofeedback. However, when biofeedback was not available, the opposite trend in FE and DFA values was observed. Regardless of changes to task constraints and the variable investigated, balance performance was positively related to complexity in every condition. Data revealed how specificity of task constraints can result in an increase or decrease in complexity emerging in a neurobiological system during balance performance.

Evaluation of Novel EMG Biofeedback for Postural Correction During Computer Use.

Postural correction is an effective rehabilitation technique used to treat chronic neck and shoulder pain, and is aimed toward reducing the load on the surrounding muscles by adopting a neutral posture. The objective of this investigation was to evaluate the effectiveness of real-time high-density surface EMG (HDsEMG) biofeedback for postural correction during typing. Twenty healthy participants performed a typing task with two forms of postural feedback: (1) verbal postural coaching and (2) verbal postural coaching plus HDsEMG biofeedback. The interface used activity from two HDsEMG arrays placed over the trapezius designed to shift trapezius muscle activity inferiorly. The center of gravity across both arrays was used to quantify the spatial distribution of trapezius activity. Planar angles taken from upper extremity reflective markers quantified cervicoscapular posture. During the biofeedback condition, trapezius muscle activity was located 12.74±3.73mm more inferior, the scapula was 2.58±1.18° more adducted and 0.23±0.24° more depressed in comparison to verbal postural coaching alone. The results demonstrate the short-term effectiveness of a real-time HDsEMG biofeedback intervention to achieve postural correction, and may be more effective at creating an inferior shift in trapezius muscle activity in comparison to verbal postural coaching alone.

Breathing biofeedback as an adjunct to exposure in cognitive behavioral therapy hastens the reduction of PTSD symptoms: a pilot study.

Although trauma-focused cognitive behavioral therapy (TF-CBT) with exposure is an effective treatment for posttraumatic stress disorder (PTSD), not all patients recover. Addition of breathing biofeedback to exposure in TF-CBT is suggested as a promising complementary technique to improve recovery of PTSD symptoms. Patients (n = 8) with chronic PTSD were randomized to regular TF-CBT or TF-CBT with complementary breathing biofeedback to exposure. PTSD symptoms were measured before, during and after TF-CBT with the Impact of Event Scale-Revised. The results show that breathing biofeedback is feasible and can easily be complemented to TF-CBT. Although PTSD symptoms significantly decreased from pre to post treatment in both conditions, there was a clear trend towards a significantly faster (p = .051) symptom reduction in biofeedback compared to regular TF-CBT. The most important limitation was the small sample size. The hastened clinical improvement in the biofeedback condition supports the idea that breathing biofeedback may be an effective complementary component to exposure in PTSD patients. The mechanism of action of breathing biofeedback may relate to competing working memory resources decreasing vividness and emotionality, similar to eye movement desensitization and reprocessing. Future research is needed to examine this.

Differential psychophysiological interactions of insular subdivisions during varied oropharyngeal swallowing tasks

The insula is a highly integrated cortical region both anatomically and functionally. It has been shown to have cognitive, social–emotional, gustatory, and sensorimotor functions. Insular involvement in both normal and abnormal swallowing behavior is well established, yet its functional connectivity is unclear. Studies of context‐dependent connectivity, or the connectivity during different task conditions, have the potential to reveal information about synaptic function of the insula. The goal of this study was to examine the functional connectivity of specific insular regions (ventral anterior, dorsal anterior, and posterior) with distant cortical regions during four swallowing conditions (water, sour, e‐stim, and visual biofeedback) using generalized psychophysiological interactions (gPPI). In 19 healthy adults, we found that the visual biofeedback condition was associated with the most and strongest increases in functional connectivity. The posterior insula/rolandic operculum regions had the largest clusters of increases in functional connectivity, but the ventral anterior insula was functionally connected to a more diverse array of cortical regions. Also, laterality assessments showed left lateralized increases in swallowing functional connectivity. Our results are aligned with reports about the insula's interconnectivity and extensive involvement in multisensory and cognitive tasks.

ExoBuilding

Our surroundings are becoming infused with sensors measuring a variety of data streams about the environment, people and objects. Such data can be used to make the spaces that we inhabit responsive and interactive. Personal data in its different forms are one important data stream that such spaces are designed to respond to. In turn, one stream of personal data currently attracting high levels of interest in the HCI community is physiological data (e.g., heart rate, electrodermal activity), but this has seen little consideration in building architecture or the design of responsive environments. In this context, we developed a prototype mapping a single occupant’s respiration to its size and form, while it also sonifies their heartbeat. The result is a breathing building prototype, formative trials of which suggested that it triggers behavioral and physiological adaptations in inhabitants without giving them instructions and it is perceived as a relaxing experience. In this paper, we present and discuss the results of a controlled study of this prototype, comparing three conditions: the static prototype, regular movement and sonification and a biofeedback condition, where the occupant’s physiological data directly drives the prototype and presents this data back to them. The study confirmed that the biofeedback condition does indeed trigger behavioral changes and changes in participants’ physiology, resulting in lower respiration rates as well as higher respiration amplitudes, respiration to heart rate coherence and lower frequency heart rate variability. Self-reported state of relaxation is more dependent on inhabitant preferences, their knowledge of physiological data and whether they found space to ‘let go’. We conclude with a discussion of ExoBuilding as an immersive but also sharable biofeedback training interface and the wider potential of this approach to making buildings adapt to their inhabitants.

Audiovisual biofeedback improves diaphragm motion reproducibility in MRI

In lung radiotherapy, variations in cycle-to-cycle breathing results in four-dimensional computed tomography imaging artifacts, leading to inaccurate beam coverage and tumor targeting. In previous studies, the effect of audiovisual (AV) biofeedback on the external respiratory signal reproducibility has been investigated but the internal anatomy motion has not been fully studied. The aim of this study is to test the hypothesis that AV biofeedback improves diaphragm motion reproducibility of internal anatomy using magnetic resonance imaging (MRI). To test the hypothesis 15 healthy human subjects were enrolled in an ethics-approved AV biofeedback study consisting of two imaging sessions spaced ∼1 week apart. Within each session MR images were acquired under free breathing and AV biofeedback conditions. The respiratory signal to the AV biofeedback system utilized optical monitoring of an external marker placed on the abdomen. Synchronously, serial thoracic 2D MR images were obtained to measure the diaphragm motion using a fast gradient-recalled-echo MR pulse sequence in both coronal and sagittal planes. The improvement in the diaphragm motion reproducibility using the AV biofeedback system was quantified by comparing cycle-to-cycle variability in displacement, respiratory period, and baseline drift. Additionally, the variation in improvement between the two sessions was also quantified. The average root mean square error (RMSE) of diaphragm cycle-to-cycle displacement was reduced from 2.6 mm with free breathing to 1.6 mm (38% reduction) with the implementation of AV biofeedback (p-value < 0.0001). The average RMSE of the respiratory period was reduced from 1.7 s with free breathing to 0.3 s (82% reduction) with AV biofeedback (p-value < 0.0001). Additionally, the average baseline drift obtained using a linear fit was reduced from 1.6 mm∕min with free breathing to 0.9 mm∕min (44% reduction) with AV biofeedback (p-value = 0.012). The diaphragm motion reproducibility improvements with AV biofeedback were consistent with the abdominal motion reproducibility that was observed from the external marker motion variation. This study was the first to investigate the potential of AV biofeedback to improve the motion reproducibility of internal anatomy using MRI. The study demonstrated the significant improvement in diaphragm motion reproducibility using AV biofeedback combined with MRI. This system can potentially provide clinically beneficial motion management of internal anatomy in MRI and radiotherapy.

Short-term memory effects of an auditory biofeedback on isometric force control: Is there a differential effect as a function of transition trials?

The aim of the present study was to investigate memory effects, force accuracy, and variability during constant isometric force at different force levels, using auditory biofeedback. Two types of transition trials were used: a biofeedback–no biofeedback transition trial and a no biofeedback–biofeedback transition trial. The auditory biofeedback produced a low- or high-pitched sound when participants produced an isometric force lower or higher than required, respectively. To achieve this goal, 16 participants were asked to produce and maintain two different isometric forces (30 ± 5% and 90 N ± 5%) during 25 s. Constant error and standard deviation of the isometric force were calculated. While accuracy and variability of the isometric force varied according to the transition trial, a drift of the force appeared in the no biofeedback condition. This result suggested that the degradation of information about force output in the no biofeedback condition was provided by a leaky memory buffer which was mainly dependent on the sense of effort. Because this drift remained constant whatever the transition used, this memory buffer seemed to be independent of short-term memory processes.

Visual Bio-Feedback System of Gait Phase in Split Belt Treadmill

We have been developing a robotic split-belt treadmill with different belt velocities and visual biofeedback of stance phase for the stroke patients to improve the symmetricity of their gait balance. In this treadmill system, a visual bio-feedback system of stance phase time of affected and unaffected legs is used. In this paper, a signal processing to eliminate spike and high frequency noises and oscillation of judge result of gait phase is discussed to indicate the stance phase time in real-time accurately. In addition, the effect of visual biofeedback of gait balance on their gait was analyzed in the determined biofeedback condition. Firstly, we conducted the gait experiment to determine the parameters in the signal processing such as cut-off frequency of low pass filter. In this experiment, the number of false judgment was calculated in normal gait, high cadence gait and simulated stroke gait. As a result, two parameters, cut-off frequency and the number of data to judge the gait phase, are set as 3.0 [Hz] and 10 respectively. In this condition, the gait phase of affected and unaffected legs are accurately displayed in front of stroke patient and physical therapist. Secondly, simulated stroke patients evaluated the effect of biofeedback of stance phase on the stance phase balance. As a result, the stance phase balance between affected and unaffected legs' stance phase was symmetrized by using visual biofeedback system.

New Aspects of the Influence of Quadriceps Femoris Muscle Stimulation Course on Functional Capabilities of the Organism

We studied the effect of a course of electrical stimulation of the quadriceps femoris muscle with submaximal contraction under biofeedback conditions on functional capabilities of the organism. In addition to the known effects, electrostimulation course modulated the content of intra- and extracellular fluid and increases MDA content and creatine phosphokinase activity, which can be a manifestation of overtreatment. Impairment of body static balance after the course was revealed. Thus, monitoring of the effects of electrostimulation is required during the course.

MIPAS-Family—evaluation of a new multi-modal behavioral training program for pediatric headaches: clinical effects and the impact on quality of life

Several meta-analyses have demonstrated that the combination of electrical muscle activity and Temperature Biofeedback could be regarded as gold standard in chronic pediatric headaches. However, these techniques seem to be uneconomical and furthermore they are not directed to improve the social competence as well as resolve possible impairments in daily activities of the child. Therefore, multi-modal behavioral techniques have been proposed, but no studies comparing these with the gold standard were conducted. The present study compared the impact of a new multi-modal behavioral education and training program—MIPAS-Family—with a combined Biofeedback treatment, evaluating clinical efficacy as well as the effect on the quality of life (QoL) of children with chronic headaches. Thirty-four children and adolescents with recurrent headache, ranging from 7 to 16 years, were randomly assigned to the MIPAS-Family (N = 19) or the Biofeedback (N = 15) condition. All patients were diagnosed by the criteria of the International Headache Society. The children and their parents completed headache diaries, diaries of daily living activities and a QoL questionnaire (KINDL®). Both groups showed significant improvements concerning the headache intensity and headache duration. We found no significant differences in the main headache parameters between both treatments. After the treatments, the children were less disturbed by their headaches in the domains school, homework, and leisure time. In conclusion, MIPAS-Family is as effective as Biofeedback but it is more cost-effective and addresses the whole family and the daily activities.

An analysis of directional changes in the center of pressure trajectory during stance

This study proposes a new approach of posturography analysis, which enables the evaluation of directional changes in the center of pressure trajectory. The concept is similar to that of so-called “stabilogram diffusion analysis”. Instead of calculating the distance traveled by the center of pressure in a certain time interval, this new method calculates the cosine of the instantaneous velocity vectors of the center of pressure, which corresponds to the amount of change in the sway direction (cosine = 1 corresponds to the identical direction; cosine = −1 corresponds to the opposite direction). This method was applied to the analysis of the experimental data in which postural sway was collected under four conditions: open eyes, closed eyes, and two auditory biofeedback conditions. In the biofeedback conditions, auditory signal was given to the subjects when the center of pressure swayed out of a certain area. As results, the differences in the postural reaction under these conditions were clearly shown using the new method. The results indicated that the subjects reacted to the auditory signals by swaying in the opposite direction with biofeedback. It was also found that the eyes open condition exhibited a more random-like profile. As this method analyzes the directional change in the postural sway, this method can be utilized cooperatively together with such a method as stabilogram diffusion analysis, which analyzes the magnitude of sway.

Respiratory Effects on Experimental Heat Pain and Cardiac Activity

Slow deep breathing has been proposed as an effective method to decrease pain. However, experimental studies conducted to validate this claim have not been carried out. We measured thermal pain threshold and tolerance scores from 20 healthy adults during five different conditions, namely, during natural breathing (baseline), slow deep breathing (6 breaths/minute), rapid breathing (16 breaths/minute), distraction (video game), and heart rate (HR) biofeedback. We measured respiration (rate and depth) and HR variability from the electrocardiogram (ECG) output and analyzed the effects of respiration on pain and HR variability using time and frequency domain measures of the ECG. Compared with baseline, thermal pain threshold was significantly higher during slow deep breathing (P = 0.002), HR biofeedback (P < 0.001), and distraction (P = 0.006), whereas thermal pain tolerance was significantly higher during slow deep breathing (P = 0.003) and HR biofeedback (P < 0.001). Compared with baseline, only slow deep breathing and HR biofeedback conditions had an effect on cardiac activity. These conditions increased the amplitude of vagal cardiac markers (peak-to-valley, P < 0.001) as well as low frequency power (P < 0.001). Slow deep breathing and HR biofeedback had analgesic effects and increased vagal cardiac activity. Distraction also produced analgesia; however, these effects were not accompanied by concomitant changes in cardiac activity. This suggests that the neurobiology underlying respiratory-induced analgesia and distraction are different. Clinical implications are discussed, as are the possible cardiorespiratory processes responsible for mediating breathing-induced analgesia.