Heart Rate Feedback Research Articles

Influences of heart rate feedback and autistic traits on affective mindreading

Although mindreading is an important prerequisite for successful social interactions, the underlying mechanisms are still matter of debate. It is unclear, for example, if inferring others’ and own mental states are distinct processes or are based on a common mechanism. Using an affect-induction experimental set-up with an acoustic heart rate feedback that addresses affective mindreading in self and others, we investigated if non-autistic study participants relied on similar information for self- and other-directed mindreading. We assumed that due to altered mindreading capacities in autism, mainly individuals with low autistic traits would focus on additional sensory cues, such as heart rate, to infer their own and their gambling partner’s affective states. Our analyses showed that the interpretation of a heart rate signal differed in self- and other-directed mindreading trials. This effect was modulated by autistic traits suggesting that individuals with higher autistic traits might not have interpreted the heart rate feedback for gambling partner ratings and differentiated less between self- and other-directed mindreading trials. We discuss these results in the context of a common mechanism underlying self- and other-directed mindreading and hypothesize that the weighting of internal and external sensory information might contribute to how we make sense of our and others’ mental states.

Convolutional neural networks to classify human stress that occurs during in‐field sugarcane harvesting: A case study

AbstractAssessing human stress in agriculture proves to be a complex and time‐intensive endeavor within the field of ergonomics, particularly for the development of agricultural systems. This methodology involves the utilization of instrumentation and the establishment of a dedicated laboratory setup. The complexity arises from the need to capture and analyze various physiological and psychological indicators, such as heart rate (HR), muscle activity, and subjective feedback to comprehensively assess the impact of farm operations on subjects. The instrumentation typically includes wearable devices, sensors, and monitoring equipment to gather real‐time data of subject during the performance of farm operations. Deep learning (DL) models currently achieve human performance levels on real‐world face recognition tasks. In this study, we went beyond face recognition and experimented with the recognition of human stress based on facial features during the drudgery‐prone agricultural operation of sugarcane harvesting. This is the first research study for deploying artificial intelligence‐driven DL techniques to identify human stress in agriculture instead of monitoring several ergonomic characteristics. A total of 20 (10 each for male and female) subjects comprising 4300 augmented RGB images (215 per subject) were acquired during sugarcane harvesting seasons and then these images were deployed for training (80%) and validation (20%). Human stress and nonstress states were determined based on four ergonomic physiological parameters: heart rate (ΔHR), oxygen consumption rate (OCR), energy expenditure rate (EER), and acceptable workload (AWL). Stress was defined when ΔHR, OCR, EER, and AWL reached or exceeded certain standard threshold values. Four convolutional neural network‐based DL models (1) DarkNet53, (2) InceptionV3, (3) MobileNetV2 and (4) ResNet50 were selected due to their remarkable feature extraction abilities, simple and effective implementation to edge computation devices. In all four DL models, training performance results delivered training accuracy ranging from 73.8% to 99.1% at combinations of two mini‐batch sizes and four levels of epochs. The maximum training accuracies were 99.1%, 99.0%, 97.7%, and 95.4% at the combination of mini‐batch size 16 and 25 epochs for DarkNet53, InceptionV3, ResNet50, and MobileNetV2, respectively. Due to the best performance, DarkNet53 was tested further on an independent data set of 100 images and found 89.8%–93.3% confident to classify stressed images for female subjects while 92.2%–94.5% for male subjects, though it was trained on the integrated data set. The comparative classification of the developed model and ergonomic measurements for stress classification was carried out with a net accuracy of 88% where there were few instances of wrong classifications.

The influence of false interoceptive feedback on emotional state and balance responses to height-induced postural threat

Postural threat elicits a robust emotional response (e.g., fear and anxiety about falling), with concomitant modifications in balance. Recent theoretical accounts propose that emotional responses to postural threats are manifested, in part, from the conscious monitoring and appraisal of bodily signals (‘interoception’). Here, we empirically probe the role of interoception in shaping emotional responses to a postural threat by experimentally manipulating interoceptive cardiac feedback. Sixty young adults completed a single 60-s trial under the following conditions: Ground (no threat) without heart rate (HR) feedback, followed by Threat (standing on the edge of a raised surface), during which participants received either false heart rate feedback (either slow [n = 20] or fast [n = 20] HR feedback) or no feedback (n = 20). Participants provided with false fast HR feedback during postural threat felt more fearful, reported feeling less stable, and rated the task more difficult than participants who did not receive HR feedback, or those who received false slow HR feedback (Cohen’s d effect size = 0.79 – 1.78). However, behavioural responses did not significantly differ across the three groups. When compared to the no HR feedback group, false slow HR feedback did not significantly affect emotional or behavioural responses to the postural threat. These observations provide the first experimental evidence for emerging theoretical accounts describing the role of interoception in the generation of emotional responses to postural threats.

Enhancing University Students’ Functional Fitness by Applying Health Programs Based on Individual Student Heart Rate Monitoring Data

The purpose of this work was to assess the impact on the students’ functional fitness of a one academic year student health-enhancing program based on equipping students with theoretical and methodological knowledge which allows them to analyze the dynamics of their own functional state and interpret digital feedback received from heart rate monitors. Studies have proven that receiving timely feedback of heart rate during the implementation of the training program, is a promising direction to enhance students functional fitness. The obtained research data can help to better understand how providing digital feedback during exercise can help improve student health and self-management skills that are important for students when planning independent physical activity programs.

Design and rationale of a pilot randomized clinical trial investigating the use of a mHealth app for sarcoidosis-associated fatigue

Fatigue is the most reported symptom in patients with sarcoidosis (SPs) and is a significant predictor of decreased quality of life that is strongly associated with stress and negative mood states. Few medications exist for treating fatigue in SPs, and outpatient physical rehabilitation programs are limited by availability and cost. Sarcoidosis in the US predominantly impacts minorities and underserved populations who are of working age and often have limited resources (e.g., financial, transportation, time off work) that may prevent them from attending in-person programs. The use of mobile health (mHealth) is emerging as a viable alternative to provide access to self-management resources to improve quality of life. The Sarcoidosis Patient Assessment and Resource Companion (SPARC) App is a sarcoidosis-specific mHealth App intended to improve fatigue and stress in SPs. It prompts SPs to conduct breathing awareness meditation (BAM) and contains educational modules aimed at improving self-efficacy.Herein we describe the design and methods of a 3-month randomized control trial comparing use of the SPARC App (10-min BAM twice daily) to standard care in 50 SPs with significant fatigue (FAS ≥22). A Fitbit® watch will provide immediate heartrate feedback after BAM sessions to objectively monitor adherence. The primary outcomes are feasibility and usability of the SPARC App (collected monthly). Secondary endpoints include preliminary efficacy at improving fatigue, stress, and quality of life. We expect the SPARC App to be a useable and feasible intervention that has potential to overcome barriers of more traditional in-person programs.

Auditory Feedback of False Heart Rate for Video Game Experience Improvement

Changes in emotions affect our physiological responses, and perhaps vice versa. We investigate a new game interaction system that uses false heart rate (fHR) feedback to improve the player experience (PX). The fHR feedback presents false HR information to players so that they perceive changes in the presented HR as being a result of alteration in PX. We introduced auditory fHR feedback into game interaction and investigated its effects through an experiment. Participants repeated gameplay of an action game while hearing heartbeat-like sounds and answered questionnaires regarding PX. Some participants heard the heartbeat-like sounds synchronized with their actual HR, whereas others heard the heartbeat-like sounds whose tempo became gradually faster or slower than their actual HR. The results indicated that an accelerating fHR feedback pattern with +5 bpm/min was appropriate for improving PX; participants were able to maintain their motivation to continue the game. The experiment also indicated that it is necessary for participants to perceive the presented heartbeat-like sounds as reflecting their actual HR. Participants did not maintain their motivation when they were told that the presented sounds were not correlated with their actual HR. The present work provides new principles for video game interaction design based on physiological measurements.

Impact of immediate and continuous heart rate feedback by dry electrode ECG on time to initiation of ventilation after birth: protocol for a randomised controlled trial

Introduction3%–8% of newborns need positive pressure ventilation (PPV) after birth. Heart rate (HR) is considered the most sensitive indicator of the newborns’ condition and response to resuscitative interventions. According to...

Effects of Interactive Music Tempo with Heart Rate Feedback on Physio-Psychological Responses of Basketball Players.

This paper introduces an interactive music tempo control with closed-loop heart rate feedback to yield a sportsperson with better physio-psychological states. A total of 23 participants (13 men, 10 women; 16–32 years, mean = 20.04 years) who are professionals or school team members further guide a sportsperson to amend their physical tempo to harmonize their psychological and physical states. The self-tuning mechanism between the surroundings and the human can be amplified using interactive music tempo control. The experiments showed that listening to interactive music had a significant effect on the heart rate and rating of perceived exertion (RPE) of the basketball player compared to those listening to asynchronous music or no music during exercise (p < 0.01). Synchronized interactive music allows athletes to increase their heart rate and decrease RPE during exercise and does not require a multitude of preplanned playlists. All self-selected songs can be converted into sports-oriented music using algorithms. The algorithms of synchronous and asynchronous modes in this study can be adjusted and applied to other sports fields or recovery after exercise. In the future, other musical parameters should be adjusted in real-time based on physiological signals, such as tonality, beats, chords, and orchestration.

Control Strategy Design of a Microblood Pump Based on Heart-Rate Feedback.

Based on the nonlinear relationship between heart rate and stroke volume, a flow model of left ventricular circulation was improved, and a variable-speed blood-pump control strategy based on heart-rate feedback was proposed. The control strategy was implemented on a system combining the rotary blood pump and blood circulation models of heart failure. The aortic flow of a healthy heart at different heart rates was the desired control goal. Changes in heart rate were monitored and pump speed was adjusted so that the output flow and aortic pressure of the system would match a normal heart in real time to achieve the best auxiliary state. After simulation with MATLAB, the cardiac output satisfied the ideal perfusion requirements at different heart rates, and aortic pressure demonstrated lifting and had good pulsatile performance when a variable-speed blood pump was used. The coupled model reflected the relationship between hemodynamic parameters at different heart rates with the use of the variable-speed blood pump, providing a theoretical basis for the blood-pump-assisted treatment of heart failure and the design of physiological control strategies.

Comparison of Heart Rate Feedback from Dry-Electrode ECG, 3-Lead ECG, and Pulse Oximetry during Newborn Resuscitation.

Background: Assessment of heart rate (HR) is essential during newborn resuscitation, and comparison of dry-electrode ECG technology to standard monitoring by 3-lead ECG and Pulse Oximetry (PO) is lacking. Methods: NeoBeat, ECG, and PO were applied to newborns resuscitated at birth. Resuscitations were video recorded, and HR was registered every second. Results: Device placement time from birth was median (quartiles) 6 (4, 18) seconds for NeoBeat versus 138 (97, 181) seconds for ECG and 152 (103, 216) seconds for PO. Time to first HR presentation from birth was 22 (13, 45) seconds for NeoBeat versus 171 (129, 239) seconds for ECG and 270 (185, 357) seconds for PO. Proportion of time with HR feedback from NeoBeat during resuscitation from birth was 85 (69, 93)%, from arrival at the resuscitation table 98 (85, 100)%, and during positive pressure ventilation 100 (95, 100)%. For ECG, these proportions were, 25 (0, 43)%, 28 (0, 56)%, and 33 (0, 66)% and for PO, 0 (0, 16)%, 0 (0, 16)%, and 0 (0, 18)%. All p < 0.0001. Conclusions: NeoBeat was faster to place, presented HR more rapidly, and provided feedback on HR for a larger proportion of time during ongoing resuscitation compared to 3-lead ECG and PO.

The effects of heart rate feedback on physical activity during treadmill exercise.

The effects of heart rate feedback on physical activity during treadmill exercise.

Psychophysiological Benefits of Real-Time Heart Rate Feedback in Physical Education.

School physical education (PE) has the potential to contribute to public-health promotion and well-being, but oftentimes students' lack of motivation toward PE or physical activity in general, especially during adolescence, diminishes, or eradicates the positive effects associated with PE. Therefore, practical approaches are required that help teachers to increase or awake students intrinsic motivation toward PE, for which self-determination theory may provide the conceptual framework. In that regard, the purpose of the present study was to examine whether the use of real-time, heart rate feedback (as a method to support students' need for autonomy and competence) during regular PE lessons has the potential to increase students' autonomous motivation and physical effort. To achieve this, we had forty healthy adolescents between 16 and 17 years of age run for 30 min either with (experimental group, EG) or without (control group, CG) real-time, individualized heart rate feedback during a regular PE class and compared physical and perceived exertion as well as joy of running between the two groups. Participants were randomly assigned to the groups. Our data revealed that participants in the EG enjoyed running more than participants in the CG (joy of running was 3.20 in the EG vs. 2.63 in the CG, p = 0.03) despite a higher physical (163 to 178 in EG vs. 141 to 156 beats per minute in the CG, p < 0.001) and perceived exertion (rating of perceived exertion of 13.22 in the EG vs. 10.59 in the CG, p = 0.02). That means, running with real-time, individualized heart rate feedback apparently increased participants' motivation to run and to enjoy running at higher levels of exertion. In that regard, real-time, individualized activity feedback should be implemented in regular PE classes systematically and repeatedly to create a controllable and attainable situation that allows students to actively adjust their own behavior to achieve appealing and realistic goals.

A Single Session of Heart Rate Variability Biofeedback Produced Greater Increases in Heart Rate Variability Than Autogenic Training.

Heart rate variability biofeedback (HRV-BF) has been confirmed to increase heart rate variability (HRV) and cardiac outflows by baroreflex in healthy populations and clinical patients. Autogenic training (AT) is common used in the psychological intervention. This study integrates a single-session of HRV-BF and AT into a high-technology mobile application (app), and examines the effects on HRV indices, breathing rates, and subjective relaxation scores. Healthy college students were recruited and assigned to the single-session HRV-BF group or AT group. Participants in the HRV-BF group received HRV-BF combined with paced breathing training, which gradually stepped down their breathing rates from 12, to 8, to 6 breaths/per min; and received feedback of HRV indices from the app. Participants in the AT group received autogenic training and feedback of heart rate from the app. A chest belt Zephyr BioHarness was connected through Bluetooth to a Zenfone5 mobile phone, it collected the signals of interbeat intervals and breathing rates at pre-training, mid-training, and post-training stages. The Kubios HRV software was used to analyze HRV indices. The results reveal higher HRV indices and lower breathing rates during mid-training and post-training in the HRV-BF group compared to the AT group. There were higher high-frequency of HRV at post-training than pre-training in the AT group. Participants of both groups increased their subjective relaxation scores after training. The HRV-BF protocol increased cardiac outflows by baroreflex and decreased breathing rates, and the AT protocol increased high-frequency of HRV. These high-technology wearable devices combined with psychological interventions will apply to various populations in the future.

Design and Experimental Evaluation of a Semi-Passive Upper-Limb Exoskeleton for Workers With Motorized Tuning of Assistance.

This article presents the H-PULSE, a novel semi-passive upper-limb exoskeleton for worker assistance, with motorized tuning of the assistive level. The H-PULSE presents novel design features compared to other passive industrial exoskeletons for the upper limbs, namely joint angle sensors for measuring shoulder flexion/extension and a novel active mechanism for regulating the assistance level. These features could enhance the effectiveness of the system. Along with the presentation of the exoskeleton design, this article reports on the system experimental evaluation with human subjects. The H-PULSE was assessed in prolonged static overhead tasks under different conditions of assistive support. The set of metrics to evaluate the effects of the device included shoulder muscular activity, heart rate, and subjective user feedback. Results show that the exoskeleton can reduce the users' muscular activity and the heart rate. Subjective questionnaires allowed the assessment of perceived exoskeleton effectiveness. In this study, the H-PULSE exoskeleton was found to be potentially effective in reducing the muscular strain while reducing the global fatigue level during prolonged continuous overhead activities.

Evaluating the stress-response of dental students to the dental school environment.

Introduction and ObjectiveDentists experience high amounts of professional stress beginning with their student years in dental school. This stress, given its early onset, may negatively impact the personal and professional lives of these individuals, as well as the quality of their clinical work. We sought to create an objective scale to evaluate the levels of stress in students at different stages of their education, as well as in practicing physicians.Materials and MethodsThirty dental students participated in this study, with 10 students each selected from junior, mid-senior, and senior classes. They were randomly divided into two groups in which one group was subjected to stressors while the other group was not. JINS MEME ES_R (JINS) smart glasses and Garmin Vivoactive 3 smartwatches were used to obtain data, including electrooculography (EOG), heart rate (HR), and accelerometer (ACC) and gyroscope (GYRO) feedback, while the subjects performed a dental exercise on a phantom tooth.ResultsThe heart rates of more experienced students were lower than those of the junior students. The EOG, ACC, and GYRO signals showed multiple differences in the measurement of amplitudes and frequency of episodes.ConclusionOur pilot results show that electronic tools, like smart glasses with software and sensors, are useful for monitoring the stress levels of dental students in preclinical operating conditions. We would like to further assess the stress levels in students performing dental procedures on phantom teeth and in later clinical interactions with patients.

An interoceptive illusion of effort induced by false heart-rate feedback.

Interoception, or the sense of the internal state of the body, is key to the adaptive regulation of our physiological needs. Recent theories contextualize interception within a predictive coding framework, according to which the brain both estimates and controls homeostatic and physiological variables, such as hunger, thirst, and effort levels, by orchestrating sensory, proprioceptive, and interoceptive signals from inside the body. This framework suggests that providing false interoceptive feedback may induce misperceptions of physiological variables, or "interoceptive illusions." Here we ask whether it is possible to produce an illusory perception of effort by giving participants false acoustic feedback about their heart-rate frequency during an effortful cycling task. We found that participants reported higher levels of perceived effort when their heart-rate feedback was faster compared with when they cycled at the same level of intensity with a veridical feedback. However, participants did not report lower effort when their heart-rate feedback was slower, which is reassuring, given that failing to notice one's own effort is dangerous in ecologically valid conditions. Our results demonstrate that false cardiac feedback can produce interoceptive illusions. Furthermore, our results pave the way for novel experimental manipulations that use illusions to study interoceptive processing.

Health and fitness benefits using a heart rate intensity-based group fitness exercise regimen

Inactivity leads to morbidity and mortality, while novel and engaging approaches to fitness improve health outcomes. The current study examined an 8-week commercial group exercise regimen for high intensity interval training (HIIT) in order to examine comprehensive metrics of health and fitness. Aerobic fitness, body composition, resting metabolic rate, blood cholesterol and glucose, in addition to resting blood pressure were quantified in a laboratory setting independent of the training facilities. Exercise training utilized multimodal HIIT-based exercises and work intensity was gauged by real-time heart rate feedback. All participants completed the required two sessions per week. Pre-Post analyses indicate aerobic fitness (Pre VO2max = 36.8 ml•kg-1•min-1; Post VO2max = 40.8 ml•kg-1•min-1), % fat (Pre = 28.1%; Post = 27.0%), resting metabolic rate (Pre = 1557 kcals; Post = 1664 kcals), resting blood pressure (Pre = 128.8/78.1 mmHg; Post = 116.7/75.4 mmHg), and circulating triacylglycerol (Pre = 100.0 mg/dl; Post = 78.7 mg/dl) were significantly altered. This study quantified improvements in aerobic fitness, body composition, resting metabolic rate, resting blood pressure, and triacylglycerol after an 8-week HIIT regimen. The implications of heart rate (HR) monitoring within franchised group exercise with wearable technology serves as an unexplored scientific approach to understand novel exercise prescriptions on health-fitness outcomes. Future research should investigate sociological aspects of program adherence, while biological applications should examine the adaptive stimuli of HIIT training on health and fitness improvements.

EmotionCheck:: A Wearable Device to Regulate Anxiety through False Heart Rate Feedback.

Previous studies indicate that the way we perceive our bodily signals, such as our heart rate, can influence how we feel. Inspired by these studies, we built EmotionCheck, which is a wearable device that can change users' perception of their heart rate through subtle vibrations on the wrist. The results of an experiment with 67 participants show that the EmotionCheck device can help users regulate their anxiety through false feedback of a slow heart rate.

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.

Feedback control of oxygen uptake during robotics-assisted end-effector-based stair climbing

ABSTRACTA heart rate (HR) feedback control system for end-effector gait rehabilitation robots was previously developed and successfully tested, but oxygen uptake () is thought to better characterize physiological exercise intensity. The aim of the present study was to identify and compare and HR dynamics, and to develop and test a controller for an end-effector robot operated in stair climbing mode. Six able-bodied subjects were recruited for controller testing. Command response, disturbance rejection and robustness were assessed by means of three quantitative outcome measures: root-mean-square (RMS) error of (), average control signal power () and RMS error of volitionally controlled power (). The nominal first-order linear model for had time constant s and steady-state gain k=0.0174 (l/min)/W. The mean time constant s for HR was significantly higher than for , where (p=0.048). Command responses for a target profile gave consistent and accurate tracking with l/min, W2 and W (). Disturbance rejection performance was also found to be satisfactory. The results of the controller tests confirm the feasibility of the proposed feedback control strategy. Robustness was verified as the single LTI controller was specific to only one of the subjects and no difference in outcome values was apparent across all subjects. Subject-specific variability in breath-by-breath respiratory noise is the main challenge in feedback control of.