Thoracic bioelectrical impedance assessment of the hemodynamic reactions to recorded road-traffic noise in young adults

Methods and evaluation of physiological measurements with acoustic stimuli-a systematic review

Objective. The detection of psychological loads, such as stress reactions, is receiving greater attention and social interest, as stress can have long-term effects on health O'Connor, Thayer and Vedhara (2021Ann. Rev. Psychol.72, 663-688). Acoustic stimuli, especially noise, are investigated as triggering factors. The application of physiological measurements in the detection of psychological loads enables the recording of a further quantitative dimension that goes beyond purely perceptive questionnaires. Thus, unconscious reactions to acoustic stimuli can also be captured. The numerous physiological signals and possible experimental designs with acoustic stimuli may quickly lead to a challenging implementation of the study and an increased difficulty in reproduction or comparison between studies. An unsuitable experimental design or processing of the physiological data may result in conclusions about psychological loads that are not valid anymore.Approach. The systematic review according to the preferred reporting items for systematic reviews and meta-analysis standard presented here is therefore intended to provide guidance and a basis for further studies in this field. For this purpose, studies were identified in which the participants' short-term physiological responses to acoustic stimuli were investigated in the context of a listening test in a laboratory study.Main Results. A total of 37 studies met these criteria and data items were analysed in terms of the experimental design (studied psychological load, independent variables/acoustic stimuli, participants, playback, scenario/context, duration of test phases, questionnaires for perceptual comparison) and the physiological signals (measures, calculated features, systems, data processing methods, data analysis methods, results). The overviews show that stress is the most studied psychological load in response to acoustic stimuli. An ECG/PPG system and the measurement of skin conductance were most frequently used for the detection of psychological loads. A critical aspect is the numerous different methods of experimental design, which prevent comparability of the results. In the future, more standardized methods are needed to achieve more valid analyses of the effects of acoustic stimuli.

Dampened autonomic nervous system responses to stress and substance use in adolescence

We investigated whether parasympathetic and sympathetic nervous system (SNS) responses to social-evaluative threat at age 14 were related to the number of substances used between ages 14 and 16 among Mexican-origin adolescents (N = 243; 70.4% had never used substances by 14). Participants completed the Trier Social Stress Test, while cardiac measures of parasympathetic and SNS activity were measured continuously using respiratory sinus arrhythmia (RSA) and pre-ejection period (PEP), respectively. Participants reported whether they had ever used alcohol, marijuana, and cigarettes, and had ever vaped nicotine in their lifetime at ages 14 and 16. Multilevel models were used to test associations between RSA and PEP responses at age 14 and substance use at 16. Among youth who had not used substances by 14, dampened RSA and PEP responses, and profiles of greater coinhibition and lower reciprocal SNS activation between RSA and PEP, at age 14 were associated with using substances by 16. Among youth who used by 14, exaggerated PEP responses were associated with using more substances by age 16. Taken together, dampened autonomic responses to social-evaluative threat predicted initiation of substance use over two years, and difficulties with coordination of physiological responses may confer risk for substance use in adolescence.

Impact of the Soundscape on the Physical Health and the Perception of Senior Adults in Senior Care Facilities

Purpose:

To explore the impact of different acoustic stimuli of varying sound pressure levels on physical responses and the perception of senior adults.

Background:

Noise-related health problems have been gaining increased attention as studies have shown an association with negative impacts on physiological parameters resulting in cardiovascular morbidity and mortality. However, a gap in knowledge exists in exploring the impact of exposure to sound recordings in the actual environment on physiological measurements.

Methods:

Five acoustic stimuli were recorded in real life and 120 senior adults listened to them in a sound treated room to analyze the impacts of low-, middle-, and high-decibel sounds on their heart rate, blood pressure, and perception. The physical responses, heart rate, and blood pressure were measured during the sound exposure, and questionnaires were administered afterward.

Results:

Exposure to different sounds resulted in fluctuations and an inconsistent trend in heart rate, systolic pressure, and diastolic pressure. According to the physical measures and subjective evaluations, sport sounds and traffic noise were given the lowest rating for preference, while music was perceived as the most comfortable.

Conclusions:

A sound pressure level below 55–65 dB(A) correlates with increased comfort and less increase in heart rate and blood pressure. Senior adults with normal hearing preferred and were most comfortable with music, while those with severe hearing impairment preferred entertainment sounds the most.

Influence of the Acoustic Environment in Hospital Wards on Patient Physiological and Psychological Indices

Patients in general wards are often exposed to excessive levels of noise and activity, and high levels of noise have been associated with depression and anxiety. Previous studies have found that an appropriate acoustic environment is beneficial to the patient's therapeutic and treatment process; however, the soundscape is rarely intentionally designed or operated to improve patient recovery, especially for psychological rehabilitation. To gain the most accurate, and least variable, estimate of acoustic environmental stimuli/properties, virtual reality (VR) technology should be used to ensure that other environmental factors are stable and uniform in order to reduce the stimulation of other environmental factors. Therefore, this study aims to discuss the influence of the acoustic environment on patient physiological/psychological indicators and the mechanism of the effect on recovery using VR technology. A digital three-dimensional (3D) model of a hospital room was constructed, and experimental subjects wore VR glasses to visualize a real ward scene. Four typical sound categories were selected to analyze the effect of the acoustic environment on recovery; physiological indicators were monitored, and psychological factors were subjectively evaluated. The results show that music plays an important role in reducing stress as it can aid in a patient's physiological (skin conduction levels) and psychological stress recovery. Furthermore, mechanical and anthropogenic sounds exert negative effects on a patient's stress recovery. However, the effect is only limited to psychological stress indicators. The interaction effects of demographic characteristics and the acoustic environment are not significant, and future studies could consider the social-economic characteristics of patients. Based on these findings, we provide evidence that indicates that a hospital's acoustic environment is an important influencing factor on the stress recovery of patients and can serve as a reference for healthcare architects and policy makers.

Short-term exposure to noise on stroke volume and left ventricular contractility: A repeated-measure study

Prolonged exposure to noise has been associated with cardiovascular disease, but the possible mechanism for its influence on cardiac activity is unknown. This study investigated the acute effects of noise exposure on 24-h ambulatory cardiac parameters among male workers. We recruited 75 volunteers in an aviation-industry cohort in 2009. Personal noise-exposure levels and individual cardiac parameters, including stroke volume (SV) and left ventricular contractility (LVC), were measured simultaneously over 24 h on working and nonworking days. Linear mixed-effects regression models were used to estimate transient and sustained effects on ambulatory SV and LVC among high-noise-exposure (≥80 A-weighted decibels [dBA]), low-noise-exposure (<80 dBA) and office workers. Every 1-dBA increase in noise exposure was significantly associated with transient changes of -1.50 (95% confidence interval [CI]: -2.18, -1.03) ml/beat in SV and -1.76 (-2.99, -1.03) L/sec in LVC at work on working days only among high-exposure workers. The 1-dBA increase in nocturnal noise exposure was also significantly associated with transiently decreased SV among high-exposure (-1.62 [-2.15, -1.22] ml/beat), low-exposure (-1.27 [-1.57, -1.03] ml/beat) and office workers (-1.09 [-1.18, -1.00] ml/beat), but only the high-exposure group had the transiently reduced LVC (-1.70, [-2.37, -1.22] L/sec) after the current noise exposure on nonworking days. Such decreasing effects persisted to become sustained decreases in 24-h ambulatory SV in high-exposure (-1.10 [-1.20, -1.01] ml/beat) and office workers (-1.13 [-1.22, -1.05] ml/beat) on working days and in all three groups (-1.19 [-1.36, -1.04]; -1.15 [-1.31, -1.02]; -1.08 [-1.13, -1.02] ml/beat, respectively) on nonworking days. No significant effect on 24-h ambulatory LVC was found in any group on working or nonworking days. Occupational and nocturnal noise exposure may have acute effects on 24-h ambulatory SV among male workers, directly influencing the cardiac function related to cardiovascular disease.

A Wrapper Feature Selection Algorithm: An Emotional Assessment Using Physiological Recordings from Wearable Sensors

Assessing emotional state is an emerging application field boosting research activities on the topic of analysis of non-invasive biosignals to find effective markers to accurately determine the emotional state in real-time. Nowadays using wearable sensors, electrocardiogram and thoracic impedance measurements can be recorded, facilitating analyzing cardiac and respiratory functions directly and autonomic nervous system function indirectly. Such analysis allows distinguishing between different emotional states: neutral, sadness, and disgust. This work was specifically focused on the proposal of a k-fold approach for selecting features while training the classifier that reduces the loss of generalization. The performance of the proposed algorithm used as the selection criterion was compared to the commonly used standard error function. The proposed k-fold approach outperforms the conventional method with 4% hit success rate improvement, reaching an accuracy near to 78%. Moreover, the proposed selection criterion method allows the classifier to produce the best performance using a lower number of features at lower computational cost. A reduced number of features reduces the risk of overfitting while a lower computational cost contributes to implementing real-time systems using wearable electronics.

Glucocorticoid metabolites in newborns: A marker for traffic noise related stress?

BACKGROUND

Traffic noise has been associated with an increased risk for several non-auditory health effects, which may be explained by a noise-induced release of stress hormones (e.g. glucocorticoids). Although several studies in children and adults have indicated an increased secretion of glucocorticoids after exposure to noise, information regarding newborns is scarce.

OBJECTIVES

To investigate the association between residential exposure to road traffic noise and postnatal stress response, as assessed by the concentration of glucocorticoids at five weeks of age.

METHODS

Residential noise exposure was estimated for each infant based on spatially detailed modeled data. Adjusted multivariable linear regression models were used to estimate the association between noise exposure and the concentration of nine glucocorticoid metabolites measured in urine of 165 infants from a prospective birth cohort in Bern, Switzerland. Noise exposure (Lden, dB) was categorized into tertiles: low (reference), medium and high.

RESULTS

Indications of a positive association were found between high road traffic noise and cortisol (% change relative to the reference: 12.1% [95% confidence interval: -10.3, 40.1%]) and cortisone (22.6% [-1.8, 53.0%]), but just the latter was borderline significant. Borderline significant associations were also found between downstream metabolites and higher road traffic noise levels; associations were found to be both positive (i.e. for β-cortolone (51.5% [-0.9, 131.5%])) and negative (i.e. for α-cortolone (-18.3% [-33.6, 0.6%]) and tetrahydrocortisol (-23.7% [-42.8, 1.9%])).

CONCLUSIONS

Our findings suggest a potential association between exposure to higher road traffic noise levels and changes in glucocorticoid metabolism in early postnatal life. A possible physiological relevance and associations with short- and long-term adverse health effects in a larger study population need to be further investigated.

The timeline of blood pressure changes and hemodynamic responses during an experimental noise exposure

BACKGROUND

Noise exposure increases blood pressure and peripheral vascular resistance in both genders in an experimental setting, as previously reported by the authors.

OBJECTIVES

The aim of this re-analysis was to present the minute-by-minute timeline of blood pressure changes and hemodynamic events provoked by traffic noise in the young and healthy adults.

METHODS

The experiment consisted of three 10-min phases: rest in quiet conditions before noise (Leq = 40 dBA), exposure to recorded road-traffic noise (Leq = 89 dBA), and rest in quiet conditions after noise (Leq = 40 dBA). Participants' blood pressure, heart rate, and hemodynamic parameters (cardiac index and total peripheral resistance index) were concurrently measured with a thoracic bioimpedance device. The raw beat-to-beat data were collected from 112 participants, i.e., 82 women and 30 men, aged 19-32 years. The timeline of events was created by splitting each experimental phase into ten one-minute intervals (30 intervals in total). Four statistical models were fitted to answer the six study questions what is happening from one minute to another during the experiment.

RESULTS

Blood pressure decreased during quiet phase before noise, increased in the first minute of noise exposure and then decreased gradually toward the end of noise exposure, and continued to decline to baseline values after noise exposure. The cardiac index showed a gradual decrease throughout the experiment, whereas total vascular resistance increased steadily during and after noise exposure.

CONCLUSIONS

The timeline of events in this 30-min experiment provides insight into the hemodynamic processes underlying the changes of blood pressure before, during and after noise exposure.

Road traffic noise effects on cardiovascular, respiratory, and metabolic health: An integrative model of biological mechanisms

BACKGROUND

Road traffic noise is a major public health issue, given the documented association with several diseases and the growing number of exposed persons all over the world. The effects widely investigated pertain to cardiovascular health, and to a lesser extent to respiratory and metabolic health. The epidemiological design of most studies has made it possible to ascertain long-term associations of urban noise with a number of cardiovascular, respiratory, and metabolic disorders and diseases; additionally, time series studies have reported short-term associations.

OBJECTIVES

To review the various biological mechanisms that may account for all long-term as well as short-term associations between road traffic noise and cardiovascular, respiratory, and metabolic health. We also aimed to review the neuroendocrine processes triggered by noise as a stressor and the role of the central nervous system in noise-induced autonomic responses.

METHODS

Review of the literature on road traffic noise, environmental noise in general, psychosomatics, and diseases of the cardiovascular, respiratory, and metabolic systems. The search was done using PubMed databases.

DISCUSSION

We present a comprehensive, integrative stress model with all known connections between the body systems, states, and processes at both the physiological and psychological levels, which allows to establish a variety of biological pathways linking environmental noise exposure with health outcomes.

CONCLUSIONS

The long- and short-term associations between road traffic noise and health outcomes found in latest noise research may be understood in the light of the integrative model proposed here.

ICBEN review of research on the biological effects of noise 2011-2014

The mandate of the International Commission on Biological Effects of Noise (ICBEN) is to promote a high level of scientific research concerning all aspects of noise-induced effects on human beings and animals. In this review, ICBEN team chairs and co-chairs summarize relevant findings, publications, developments, and policies related to the biological effects of noise, with a focus on the period 2011-2014 and for the following topics: Noise-induced hearing loss; nonauditory effects of noise; effects of noise on performance and behavior; effects of noise on sleep; community response to noise; and interactions with other agents and contextual factors. Occupational settings and transport have been identified as the most prominent sources of noise that affect health. These reviews demonstrate that noise is a prevalent and often underestimated threat for both auditory and nonauditory health and that strategies for the prevention of noise and its associated negative health consequences are needed to promote public health.