JS and UMN acknowledge funding by the Volkswagen Foundation (Az. 84905). We thank the University of Marburg for funding participant reimbursements and the Universitaetsstiftung of the University of Marburg for funding the biochemical analyses. Furthermore, we thank Johanna M. Doerr for her contribution to the study design and Nadine Skoluda for her involvement in the analysis of the saliva samples.

This protocol follows the guidelines of the local ethics committee of the University of Marburg; for all reported studies19,20,21, approval was obtained. Obtain approval from the Institutional Review Board (IRB), with special attention to potential intrusiveness of study participation on daily-life routines and with special attention to the collection of salivary biomarkers for stress.
1. Study Design: Sampling Protocol
<ol>
	<li>Decide on the number of days, as most studies involving multiple assessments typically run from 3 d&#160;to 3 weeks22. Choose multiple consecutive days (e.g., at least 7 d, to encompass both weekdays and weekend days) in order to gain representative insights into the daily life of the participants.</li>
	<li>Decide on a number of assessments per day. Distribute assessments over the day, spanning representative periods between awakening and bedtime (e.g., 6 assessments/d).</li>
	<li>Decide on the distribution of assessments per day (e.g., assessments can either be event-based, time-based, or a combination of these two designs)9. 
	NOTE: Keep in mind that current recommendations prefer event-based procedures for the sampling of rare events only, mostly for the reason of compliance and to keep up the motivation of participants. Use a combination of event-based and time-based assessments.
	<ol>
		<li>Due to the diurnal rhythm of salivary cortisol and salivary alpha-amylase, use an event-based assessment directly after waking up.</li>
		<li>Relative to this assessment, schedule one subsequent assessment 30 min after waking up and schedule further fixed assessments at 12:00 h (before lunch), 14:00 h, 18:00 h, and 21:00 h (bedtime). 
		NOTE: The study protocol described here scheduled the following assessments in each study: directly after awakening (event-based), 30 min after awakening, 10.0019,21/11.0020 (fixed), 14.00 (fixed), 18.00 (fixed), 21.00 (fixed).</li>
	</ol>
	</li>
</ol>
2. Selection of Participants
<ol>
	<li>Perform an a priori power analysis, as recommended by Bolger, Stadler, and Laurenceau23, if one has a priori knowledge on the expected effect sizes.</li>
	<li>Cautiously select the study participants and define the following inclusion criteria:
	<ol>
		<li>Ensure that the participants&#39; age range is as narrow as possible (e.g., 18 to 35 years of age) or consider it to be a confound and treat it statistically as such. Participants&#39; Body Mass Index (BMI) should be equal to or lower than 30 (see step 3.1). The participants should either be nonsmokers or should smoke less than five cigarettes per week.</li>
		<li>Make sure to only include participants who do not consume drugs (no consumption of cannabis within the last 2 weeks, no consumption of any other psychotropic substances within the last 4 weeks). Furthermore, ensure that the participant does not take any medication (except for Hormonal Contraceptives (HC) in females, which should be recorded and considered within statistical analyses).</li>
		<li>Only include participants who do not have any chronic somatic or psychiatric disease (according to self-reports based on the Patient Health Questionnaire (PHQ) 24. 
		NOTE: If interested in the effects of music listening on psychobiological stress in specific patient populations (e.g., patients with fibromyalgia syndrome), please adjust these inclusion criteria (e.g., define inclusion criteria for patients with fibromyalgia syndrome based on the research criteria25,26).</li>
	</ol>
	</li>
	<li>Assess the following covariates. 
	NOTE: Covariates should be assessed once using paper-and-pencil questionnaires.
	<ol>
		<li>Due to the assessment of biological parameters, control for BMI&#160;and gender. Either define inclusion criteria regarding BMI and gender (e.g., include only those subjects who have a BMI equal to or lower than 30, or include only men or women), or statistically control for the influence of BMI and gender.</li>
		<li>Concerning the association between music listening and stress, control for musical expertise and music preference (e.g., by means of the Music Preference Questionnaire (MPQ))27 in order to test hypotheses on differential effects concerning the association between music listening and stress based on personal music preference and expertise.</li>
		<li>Ask participants to complete the Trier Inventory for Chronic Stress28 and/or the Perceived Stress Scale29 to test hypotheses regarding the influence of overall stress levels on the association between music listening and current stress.</li>
	</ol>
	</li>
</ol>
3. Meeting with the Participants before the Assessment
<ol>
	<li>Schedule an introductory session with the participants to familiarize them with the electronic diary device, questionnaires, and saliva collection method.</li>
	<li>Provide participants with a mobile electronic diary device on which they can address the items occurring during the ambulatory assessment
	<ol>
		<li>Familiarize all participants with how to handle the electronic diary device.</li>
		<li>Provide each participant with information on how the mobile electronic diary device is used (e.g., how to turn it on and off, how to mute and unmute the alarm, how to react when an assessment is missed, how frequently to recharge it and how to start the application presenting the items).</li>
		<li>Explain and demonstrate all functions concerning the study.</li>
	</ol>
	</li>
	<li>Prepare a study manual in which the study material, the items occurring in the ambulatory assessment, and the procedure for the collection of saliva are explained in sufficient detail. In this manual, describe each item in detail by explaining each response option. 
	NOTE: Make sure to do a trial run and review the manual with each participant. Thus, provide particular instructions to the participant, both face-to-face and written in the manual, before the assessment period starts.</li>
	<li>Provide the participant with contact details in case of technical problems.</li>
	<li>Instruct the participant to start the first assessment the day following the introductory session.</li>
	<li>Set a date for the postmonitoring session after completion of data collection.</li>
</ol>
4. Items on Music Listening
NOTE: All items on music listening are presented via the electronic diary device.
<img alt="Figure 1" src="/files/ftp_upload/54920/54920fig1.jpg" /> 
Figure 1: Exemplary Screenshots from Mobile Diary Devices. Using electronic diary devices, participants can be investigated in their daily lives while they go about their daily routines. <a href="https://cloudfront-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54920/54920fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<ol>
	<li>First, use a filter question and ask whether music listening has occurred since the last assessment.</li>
	<li>Define what is meant by music listening by providing examples for music listening in daily life. Distinguish between passive music listening (e.g., background music while shopping) and active or deliberate music listening (e.g., music listening that is in the focus of attention).</li>
	<li>Ask subsequent items (e.g., valence, arousal, and reasons for music listening) that cover a more in-depth characterization of the music listening episode when participants report having listened to music.
	<ol>
		<li>Ask for the perceived valence (ranging from sad to happy on a visual analogue scale) and perceived arousal (ranging from relaxing to energizing on a visual analogue scale) of the music that was listened to.</li>
		<li>Ask the participant to define two qualitative characteristics of the music they listened to using different response scales. On the one hand, ask them to rate whether the experience is sad or happy. On the other hand, ask whether the music is relaxing or energizing. 
		NOTE: The ratings refer to the participant&#39;s subjective experience of the music.</li>
		<li>Ask the participant to try to make a rating. If this is not possible, ask the participant to choose the middle of the scale.</li>
		<li>In case the participant listens to more than one piece of music, please ask the participant to make a rating representing the majority of music listened to. That is, if the participant listens to both sad and happy music on the radio, ensure that the classification represents the predominant experience of the music.</li>
	</ol>
	</li>
	<li>Assess the reasons for music listening by asking the participant to choose the main reason for music listening (among relaxation, distraction, activation, and reducing boredom). 
	NOTE: We selected the reasons for music listening that have been reported most frequently in previous research5,6. Depending on the research question, other reasons may be chosen as well (e.g., emotion regulation, aesthetic enjoyment, and cognitive stimulation). However, please remember to keep the number of items to a minimum in order to maintain high compliance with the protocol.
	<ol>
		<li>Ask the following questions:</li>
		<li>Ask if the participant listened to music in order to relax. 
		NOTE: This can be due to some prior stressful event or to the general need to relax.</li>
		<li>Ask if the participant listened to music for activation. 
		NOTE: For example, this means that music was chosen to sing along to, to move with, or to activate oneself.</li>
		<li>Ask if the participant listened to music for distraction. 
		NOTE: Meaning, to distract from a certain topic or from certain thoughts.</li>
		<li>Ask if the participant listened to music because there were no other alternatives available for reducing boredom. 
		NOTE: In contrast to distraction as the reason for music listening, here, music is not meant to distract from a certain topic or thoughts. Rather, music is listened to in order to pass time.</li>
	</ol>
	</li>
	<li>Assess the characteristics of the listening situation.
	<ol>
		<li>Ask the participant who else was present during listening to music. 
		NOTE: In accordance to Juslin et al.6, ask the participant to choose among the following response options: &#34;I was alone while listening to music,&#34; &#34;Friends were present while listening to music,&#34; and &#34;Acquaintances were present while listening to music.&#34;</li>
		<li>Additionally, ask whether the participant was in the presence of strangers while listening to music6. 
		NOTE: If anyone is specifically interested in the role of social context factors on the stress-reducing effect of music listening, consider asking&#160;the participant whether interactions with other people occurred and how these interactions are rated (negative-positive). Furthermore, assess social support/attachment to determine whether these factors moderate the stress-reducing effect of music listening.</li>
		<li>Consult the appropriate literature on studies investigating music listening in daily life to learn more about these context variables6,18.</li>
	</ol>
	</li>
</ol>
5. Assessment of Psychobiological Stress
NOTE: Stress is a multidimensional phenomenon that is assessed via subjective self-report as well as via physiological markers of stress. At each assessment, both data on subjective stress levels and on physiological markers of stress must be collected.
<ol>
	<li>Measure subjective stress using a single-item30 indicating how stressed they feel at the moment (e.g., on a five-point Likert scale ranging from &#34;not at all&#34; to &#34;very much&#34;). 
	NOTE: This item should be presented using the electronic diary device.</li>
	<li>Immediately after having provided subjective information on music listening and stress, collect saliva samples for the later assessment of salivary cortisol and salivary alpha-amylase as neuroendocrine and autonomic stress markers, respectively, using standard procedures. 
	NOTE: There are commercially available assays for both analytes, e.g., enzyme linked immunosorbent assays.</li>
	<li>Preparation of saliva vials 
	NOTE: For the concomitant assessment of salivary cortisol and alpha-amylase, use the passive drool method, which controls for the effects of mastication, textual stimulation, or interferences of absorbent material with assay procedures31.
	<ol>
		<li>Prelabel the saliva vials. Use a simple, unique code for each vial. 
		NOTE: This code consists of the study number + participant code + day of sampling + time of day.</li>
		<li>Weigh the saliva vials both before and after study participation to determine the salivary flow rate (which is calculated by determining the saliva volume (the post- to pre-weight difference) divided by the collection time (mL/min)).&#160;</li>
		<li>Split the samples according to the day of sampling by placing all samples from one day and the corresponding numbers of straws into a small plastic bag.</li>
	</ol>
	</li>
	<li>Saliva Collection
	<ol>
		<li>Provide participants with particular instructions for the saliva collection as follows.
		<ol>
			<li>In order to avoid contamination with blood, sugar, or acidity, instruct the participants not to brush their teeth within 30 min prior to saliva sampling or to have dental treatment 24 h before saliva sampling. 
			NOTE: Major meals should not be consumed within 60 min prior to sampling; snacks and caffeinated or alcoholic beverages should not be consumed within 30 min prior to sampling.</li>
			<li>Document the intake of food, drinks, and nicotine by means of the mobile electronic diary device by asking if the participate ate/drank/smoked within the last two hours (0: &#34;no,&#34; 1: &#34;yes&#34;).</li>
			<li>Instruct the participants to rinse their mouth with tap water 10 min prior to sampling.</li>
			<li>Instruct the participants to document vigorous physical activity 2 h prior to sampling. Ask the participants if they were active. If yes, ask how active they have been during the last 2 h. Instruct the participants to respond with &#34;not at all,&#34; &#34;very little,&#34; &#34;moderately,&#34; or &#34;vigorously.&#34;</li>
			<li>Instruct the participant to store the samples at or below -20 &#176;C as soon as possible (on the evening of each day at the latest) to prevent bacterial growth. In case participants do not have immediate access to a freezer, they should be asked to store the samples in a refrigerator in the meantime.</li>
		</ol>
		</li>
		<li>Collect a saliva sample for demonstration purposes.
		<ol>
			<li>Ask the participant to swallow once. Then, ask the participant to accumulate saliva by not swallowing for the next 2 min.</li>
			<li>Set a timer (2 min are usually sufficient) on the mobile electronic diary device.</li>
			<li>Hold the vial and straw ready. After 2 min, ask the participant to transfer all accumulated saliva into the vial. 
			NOTE: Participants can either use the straw to transfer all accumulated saliva into the vial, or they can transfer all accumulated saliva without the straw into the vial.</li>
			<li>Then, ask the participant to enter the code written on&#8232;the vial as a compliance check at the end of each assessment time point.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
6. Meeting with the Participants after the Assessment
<ol>
	<li>Ask participants to return to the laboratory to hand over the study equipment after study completion (i.e.&#160;the electronic diary device and the saliva samples).</li>
	<li>Conduct a standardized post-monitoring interview asking for any problems that may have occurred during the study, interference of study participation with daily-life routines, and overall satisfaction with the study participation.</li>
</ol>
7. Statistical Handling
<ol>
	<li>Prepare the data set by excluding participants with less than 50% of the assessments completed.</li>
	<li>Check the data for a normal distribution. As salivary cortisol and salivary alpha-amylase are usually not normally distributed, transform the data (e.g., using the formula ln(x) + 10). 
	NOTE: Due to the nested structure of the data (i.e.&#160;repeatedly-assessed music listening and psychobiological stress are nested in each person), analyze the data using Hierarchical Linear Modeling (HLM)32 in accordance with the procedure described by Woltman, Feldstain, MacKay, and Rocchi33. Analyses should at least control for the time of day on level-1 and for BMI and gender on level-2. Calculate the amount of explained variance as an indicator for effect size using the formula provided by Singer and Willet34.</li>
</ol>

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N., Sloboda, J. . <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Handbook of Music and Emotion. , (2011).</li><li>Fancourt, D., Ockelford, A., Belai, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+psychoneuroimmunological+effects+of+music:+A+systematic+review+and+a+new+model.">The psychoneuroimmunological effects of music: A systematic review and a new model.</a> Brain Behav Immun. 36, 15-26 (2014).</li><li>Kreutz, G., Murcia, C. Q., Bongard, S., MacDonald, R. A. R., Kreutz, G., Mitchell, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Music, Health, &amp; Wellbeing. , (2012).</li></ol>

The authors have nothing to disclose.

Here, a study protocol is presented on how to investigate the effects of music listening on psychobiological stress in daily life. The advantage of the ambulatory assessment design is that the effects of music listening on stress can be investigated in the natural habitat of the participants while they are going about their daily routine.
As this study protocol assesses past music listening and momentary stress, short-term effects of music listening on stress can be examined. In line with experimental studies, a stress-reducing effect of music listening, depending on characteristics of the music and depending on characteristics of the situation, was found. In this regard, ambulatory assessment studies allow for further characterization of this association. As music listening in many different situations is captured, the role of characteristics of the music (e.g., valence and arousal) as well as characteristics of the situation (e.g., the reasons for music listening and the presence of others while listening to music) can be explored across various different situations.
Critical Steps within the Protocol
The descriptions provided in the manual are critical to the data quality. For example, if a proper definition for what is meant by music listening is not given by providing examples for music listening in daily life, participants might define music listening episodes differently. Therefore, it should be clearly specified whether participants are asked to report any music listening that occurs or whether participants are asked to focus on deliberate music listening only. The collection of saliva samples in daily life might be experienced unpleasant by some participants in the beginning of the study. However, these feelings vanish almost immediately. The prelabeling and preparation of the samples is essential in order to reduce participant burden and to further increase compliance with the protocol. Furthermore, oral and written instructions on how to provide a saliva sample are of the utmost importance. In this regard, participants should be equipped with a written manual containing the abovementioned precautions and instructions.
Modifications of the Design
The advantage of the items on music listening, as they are described in this protocol, is that they allow studying the temporal dynamics of the effects of past music listening on current stress. Thus, this study protocol is sound and safe for research questions addressing these intermediate effects. However, if acute effects of music listening on stress are of interest, modifications by means of event-based sampling schedules should be applied. In case event-based schedules might not be possible, both momentary music listening and momentary stress should be assessed in order to examine simultaneous effects. There are studies in which both simultaneous and past music listening are assessed15,18. Furthermore, in order to prevent reliance solely on subjective self-reports of music listening, the design can be modified by objectively assessing music listening. In this regard, Juslin et al.6 discuss the use of the electronically-activated recorder35 to objectively assess the sound environment of participants. Furthermore, music streaming platforms might be used to track the exact music titles that participants listen to.
Limitations of the Technique
The cautious interpretation of the findings gathered when using this study is warranted. First of all, conclusions regarding causality are restricted. As no random assignment to experimental conditions takes place, study results should be interpreted as associations. Nevertheless, this does not affect the quality of results, as the number of observations is high in ambulatory assessment studies. Thus, it is quite unlikely that associations are driven by other extraneous variables. Furthermore, controlling for variables associated with salivary cortisol and salivary alpha-amylase (such as smoking, drinking, eating, and physical activity) further increase the reliability and validity of the results36,37. Second, the concomitant assessment of salivary cortisol and salivary alpha-amylase deserves special attention as well. Salivary cortisol and salivary alpha-amylase underlie different diurnal rhythms13 and show distinct temporal dynamics in reaction to a stressor38. Therefore, event-based methods might be warranted when the acute effects of music listening on psychobiological markers are of interest. Then, the time-lagged collection of salivary alpha-amylase and salivary cortisol relative to music listening is necessary in order to account for the distinct temporal dynamics of salivary alpha-amylase and salivary cortisol. Third, it is important to note that subjective stress is assessed using a single-item approach, as the number of items must be cautiously balanced against the burden for participants. Therefore, a more comprehensive assessment of stress might improve the validity.
Significance of the Technique with Respect to Existing Methods
Although there are a few studies assessing the effects of music listening on daily life, they solely rely on self-reports6,18,39,40. No study so far has investigated the effects of music listening on psychobiological stress in daily life. Rather, until now, physiological effects of music listening were predominantly examined in experimental studies2,3,41,42,43. Laboratory studies allow for control over a wide range of potential confounders and, at the same time, facilitate the assessment of biological stress markers using invasive equipment (such as needles for blood collection). However, with the advancement of salivary stress markers, the assessment of psychobiological stress is not limited to the constraint of the laboratory anymore. Thus, the significance of this approach is that it provides methodological considerations on how to design studies in daily life that allow for the investigation of the effects of music listening on stress beyond the scope of subjective stress ratings.
Future Applications after Mastering the Technique
Assessing the effects of music listening on psychobiological stress in daily life will allow for important insights into mechanisms underlying the health-beneficial effect of music listening. With music listening a popular, cost-effective, and easily-applicable activity of daily life, interventions can be developed that specifically target music listening behavior in daily life. By means of ecological momentary interventions, specific populations (e.g., highly stressed individuals) can be reminded to listen to music for relaxation and stress reduction purposes. Furthermore, as smartphones allow for the assessment of physiological stress markers, participants can receive immediate biofeedback on how music listening affects their physiological stress levels. Thus, this protocol helps investigating the potential of music listening as a means of stress reduction in daily life. Knowledge gathered based on this protocol will be of great importance to the design of music interventions in daily life.
Conclusion
A study protocol for assessing the effects of music listening on psychobiological stress in daily life is presented. Studies set in daily life offer important avenues for research and, at the same time, bear some challenges. The high ecological validity and the high temporal resolution of processes that can be captured in daily life are two important advantages of ambulatory assessment studies. Beyond the scope of the constraints of experimental environments, research results with high ecological value can be gathered, allowing for the translation of research findings into daily life. At the same time, internal validity cannot be as high as in experimental studies. Therefore, diligent recruitment, diligent preparation of study materials, and cautious interpretation of the results are necessary.

Music listening is associated with stress-reducing effects1,2. However, most previous studies were conducted in experimental settings, investigating highly selective patient populations. In particular, many studies were set in surgical settings, in which music listening occurs either before, during, or after a stressful procedure3. Although some of these studies show beneficial effects of listening to music, the findings remain equivocal. This might be due to a number of methodological reasons (i.e.&#160;different study methodologies and different study designs may lead to different results). For example, the artificial setting of a laboratory-based study makes it unclear whether findings from these experimental studies can be transferred to real-life environments. As music listening is a popular activity of daily life4 that is often used for relaxation purposes5,6,7, it is of the utmost importance to study the effects of music listening on psychobiological stress (and its potential underlying mechanisms) in everyday life settings that are characterized by high ecological validity.
Studies set in daily life are often referred to as Ecological Momentary Assessments (EMA), Experience Sampling Methods (ESM), or Ambulatory Assessments (AA)8. Common to all of these approaches is the fact that data is captured repeatedly over time in the real-world environment of the participants. According to Shiffman, Stone, and Hufford9, studies set in daily life thus allow for (a) characterizing individual differences, (b) describing natural history, (c) assessing contextual associations, and (d) documenting temporal sequences. Therefore, it is possible to study dynamic relations among variables of interest with a minimum of recall bias and a maximum of ecological validity9. Although the terms EMA, ESM, and AA are often used interchangeably, certain distinctions must be made8.
Whereas EMA and ESM refer to the assessment of subjective self-reports, AA is defined as the simultaneous assessment of self-reports, behavior records, and/or physiological measurements in daily life while participants are going about their daily routine10. AA studies are characterized by repeated measures of current experiences and behaviors in conjunction with physiological data11. Furthermore, AA allows the measurement of stress in daily life from a psychobiological perspective, as self-reports and physiological markers can be assessed in the natural habitat of the participants. The Hypothalamic-Pituitary-Adrenal (HPA) axis and the Autonomic Nervous System (ANS) are two prominent stress-sensitive systems in the body. The HPA axis is responsible for the endocrine stress response. When experiencing stress, this axis is activated. This activation can be measured by the secretion of the hormone cortisol. The autonomic stress response can be measured via a range of autonomic markers, such as heart rate and skin conductance. A relatively new biomarker reflecting the activity of the ANS is the salivary enzyme alpha-amylase12. Both HPA axis and ANS activity can be noninvasively and concomitantly measured in saliva by means of salivary cortisol and salivary alpha-amylase, respectively13.
Studies set in daily life encompassing both subjective as well as physiological markers of stress are still rare, as most of the studies on music listening in daily life rely on subjective self-reports6,7,14,15,16,17. From these studies, it can be concluded that music listening is a popular activity of daily life15,17 that is associated with beneficial effects for subjective well-being6,7,18. Most interestingly, many studies find that music listening in daily life is associated with subjective feelings of relaxation6,7. Furthermore, relaxation is a common reason for music listening in daily life6. On the other hand, ambulatory assessment studies on the stress-reducing effect of music listening &#8212; particularly those encompassing both psychological as well as physiological indicators for stress &#8212; are very rare. We have previously shown in two ambulatory assessment studies that music listening is associated with a stress-reducing effect in healthy participants19,20. In contrast to these findings in healthy young adults, we were not able to find a stress-reducing effect of music listening in a patient sample21.
Thus, it is of particular importance to study the effects of music listening in daily life using ambulatory assessment, as this approach allows the examination of a broad variety of situations in which music listening occurs with high temporal resolution (in comparison to an artificial situation in an experiment) and high external validity. By means of ambulatory assessment studies, it is possible to investigate context factors influencing the effects of music listening in daily life. At the same time, the underlying mechanisms can be investigated by means of concomitantly assessing physiological parameters. This approach renders it possible to unravel the complex mechanisms underlying the stress-reducing effect of music listening in daily life.
This protocol demonstrates how to assess the effects of music listening on psychobiological stress in daily life by elaborating on (1) study design, (2) materials and methods, (3) selection of participants, and (4) statistical considerations, based upon the aforementioned studies19,20,21.

<table><tbody><tr><td>SaliCap Set</td><td>IBL International GmbH, a Tecan Group company</td><td>RE69985</td><td>Sampling tubes for collection of saliva samples to be used in the IBL Saliva Immunoassays</td></tr><tr><td>Cortisol Saliva ELISA</td><td>IBL International GmbH, a Tecan Group company</td><td>RE52611</td><td>Enzyme Immunoassay for the quantitative determination of free cortisol in human saliva</td></tr><tr><td>Calibrator f.a.s. w/o diluent</td><td>Roche Diagnostics</td><td>10759350190</td><td>Ready-for-use calibrator consisting of a buffered description aqueous solution with biological materials added as required to obtain desired component levels.</td></tr><tr><td>Precinorm U</td><td>Roche Diagnostics</td><td>10171743122</td><td>Ready-for-use control</td></tr><tr><td>Precipath U</td><td>Roche Diagnostics</td><td>10171760122</td><td>Ready-for-use control</td></tr><tr><td>AMY EPS HIT 917 liquid</td><td>Roche Diagnostics</td><td>11876473 316</td><td>R1: &amp;alpha;-glucosidase; R2: 4,6-ethylidene-(G7) p-nitrophenyl-(G1)-&amp;alpha;,D-maltoheptaoside</td></tr><tr><td colspan="4">Further materials include typical laboratory utensils, &lt;em&gt;e.g.&lt;/em&gt;, micropipettes, oribtal shaker, vortex mixer, 8-channel micropipettor, wash bottle, automated or semi-automated microtiter plate washing system, precision scale, microtiter plate reader capable of reading absorbance.</td></tr><tr><td>Apple iPod touch, 8 GB, 5&lt;sup&gt;th&lt;/sup&gt; Generation</td><td>Apple Inc.</td><td>n/a</td><td>mobile diary device</td></tr><tr><td>iDialogPad</td><td>Mutz Elektronik Entwicklung</td><td>n/a</td><td>software for programming items occuring in the ambulatory assessment</td></tr></tbody></table>

assessing the effects of music listening on psychobiological stress in daily life

Music listening is associated with stress-reducing effects. However, most of the results on music listening and stress were gathered in experimental settings. As music listening is a popular activity of daily life, it is of utmost importance to study the effects of music listening on psychobiological stress in an everyday, daily-life setting. Here, a study protocol is presented that allows the assessment of associations between music listening and psychobiological stress in daily life by noninvasively measuring salivary cortisol (as a marker of the Hypothalamic-Pituitary-Adrenal (HPA) axis) and salivary alpha-amylase (as a marker of the Autonomic Nervous System (ANS)). The protocol includes advice on the study design (e.g., sampling protocol), the materials and methods (e.g., the assessment of psychobiological stress in daily life, the assessment of music listening, and the manual), the selection of participants (e.g., the approval of the institutional review board and inclusion criteria), and the statistical analyses (e.g., the multilevel approach). The representative results provide evidence for a stress-reducing effect of music listening in daily life. Particularly, specific reasons for listening to music (especially relaxation), as well as the presence of others while doing so, increase this stress-reducing effect. At the same time, music listening in daily life differentially affects the HPA axis and ANS functioning, thus emphasizing the need for a multi-dimensional assessment of stress in daily life.

This protocol is meant to provide one example of how the effects of music listening on psychobiological stress in daily life can be examined. The procedures are designed to investigate the associations between music listening, subjective stress reports, secretion of salivary cortisol, and activity of salivary alpha-amylase.
The representative results presented are examples from three publications of our work group, published in Psychoneuroendocrinology19,20 and Frontiers in Human Neuroscience21. Please refer to these papers for a more detailed description of both theoretical background and results. In Study 119, a total of 55 healthy participants were examined for a total of 10 d. A subsample of 25 participants provided saliva samples on 4 d. In Study 220, a total of 53 healthy participants provided a saliva sample after each assessment for the duration of 7 consecutive d. In Study 3, a total of 30 female patients with fibromyalgia syndrome were examined for 14 consecutive days21.
Music Listening and Psychobiological Stress
In Study 1, deliberate music listening was associated with lower subjective stress levels. However, no effects on psychobiological markers of stress were found (see Figure 2). In Study 2 and 3, no effects of mere music listening on psychobiological stress were found20,21.
<img alt="Figure 2" src="/files/ftp_upload/54920/54920fig2.jpg" /> 
Figure 2: Music Listening and Psychobiological Stress (modified from Linnemann, Ditzen et al.19). Data from Linnemann, Ditzen et al.19 shows that music listening was associated with lower subjective stress. However, there was no effect on the secretion of cortisol or the activity of alpha-amylase. <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54920/54920fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Perceived Valence and Arousal of Music and Stress
The perceived arousal of the music was associated with salivary alpha-amylase activity in Studies 1 and 219,20. In Study 1, music that was rated as low in arousal predicted reduced salivary alpha-amylase activity (UC = 0.01, t(110) = 2.272, p = 0.025) with arousal explaining 3.55% of the variance in salivary alpha-amylase19. In Study 2, the same pattern of results emerged, with music low in arousal reducing salivary alpha-amylase activity20. In all studies, no effect of perceived valence on psychobiological stress were found19,20,21.
Reasons for Music Listening and Stress
In Studies 1 and 2, only music that was listened to for the &#8220;relaxation&#8221; reason yielded lower subjective stress ratings. In Study 1, the &#8220;relaxation&#8221; reason explained 6.50% of the variance in stress levels19 (see Figure 3A). Concerning salivary cortisol concentrations, it was shown that in accordance with the results on self-reported stress, music that was listened to for the &#8220;relaxation&#8221; reason yielded lower salivary cortisol concentrations (UC = &#8722;0.48, t(113) = &#8722;3.513, p &#8804; 0.001), explaining 12.44% of the variance in salivary cortisol19 (see Figure 3C). In Study 2, music that was listened to for the &#8220;relaxation&#8221; reason was associated with lower subjective stress levels20 (see Figure 3B). In Study 3, only music that was listened to for the &#8220;activation&#8221; reason was associated with lower subjective stress, explaining 2.42% of the variance in subjective stress21.
<img alt="Figure 3" src="/files/ftp_upload/54920/54920fig3.jpg" /> 
Figure 3: Mean Subjective Stress Level and Mean Secretion of Salivary Cortisol Depending on Reasons for Music Listening (modified from Linnemann et al.19 as well as modified from Linnemann, Strahler and Nater20). In both studies19,20, subjective stress was lowest, when music was listened to for the reason of relaxation. Furthermore, the secretion of salivary cortisol was lowest when music was listened to for the reason of relaxation19. Panels A and C refer to data from Linnemann, Ditzen et al.19, whereas panel B refers to data from Linnemann, Strahler and Nater20. <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54920/54920fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
Presence of Others during Music Listening and Stress
In Study 2, the social context of the listening situation was assessed. It was shown that listening to music in the presence of others was associated with lower subjective stress reports, lower salivary cortisol secretion, and higher salivary alpha-amylase activity20. Most interestingly, the effect of music listening in the presence of others exceeded the effect of mere music listening and of the presence of others when the assessment was triggered (Figure 4).
<img alt="Figure 2" src="/files/ftp_upload/54920/54920fig4.jpg" /> 
Figure 4: Mean Subjective Stress Level and the Presence of Others while Listening to Music (reprint from Linnemann, Strahler, and Nater20). Subjective stress was the lowest when participants listened to music in the presence of others. Furthermore, there was a significant interaction of the presence of others while listening to music and the presence of others when the assessment was triggered. Thus, subjective stress was lowest when music was listened to in the presence of others and others were present when the assessment was triggered. <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54920/54920fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

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Assessing the Effects of Music Listening on Psychobiological Stress in Daily Life

A study protocol is presented on how to assess associations between music listening and psychobiological stress (as measured by subjective stress levels, salivary cortisol, and salivary alpha-amylase) in daily life. Advice on study design, materials, methods, selection of participants, and statistical handling is provided. Representative results are presented and discussed.

Music listening is associated with stress-reducing effects. However, most of the results on music listening and stress were gathered in experimental ...

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13.2K Views.  University of Marburg. A study protocol is presented on how to assess associations between music listening and psychobiological stress (as measured by subjective stress levels, salivary cortisol, and salivary alpha-amylase) in daily life. Advice on study design, materials, methods, selection of participants, and statistical handling is provided. Representative results are presented and discussed. 

Video: Assessing the Effects of Music Listening on Psychobiological Stress in Daily Life

An Alternative to the Traditional Cold Pressor Test: The Cold Pressor Arm Wrap

Recently research on the relationship between stress and cognition, emotion, and behavior has greatly increased. These advances have yielded insights into important questions ranging from the nature of stress&#39; influence on addiction1 to the role of stress in neural changes associated with alterations in decision-making2,3. As topics being examined by the field evolve, however, so too must the methodologies involved. In this article a practical and effective alternative to a classic stress induction technique, the cold pressor test (CPT), is presented: the cold pressor arm wrap (CPAW). CPT typically involves immersion of a participant&#39;s dominant hand in ice-cold water for a period of time4. The technique is associated with robust activation of the sympatho-adrenomedullary (SAM) axis (and release of catecholamines; e.g.&#160;adrenaline and noradrenaline) and mild-to-moderate activation of the hypothalamic-pituitary-adrenal (HPA) axis with associated glucocorticoid (e.g.&#160;cortisol) release. While CPT has been used in a wide range of studies, it can be impractical to apply in some research environments. For example use of water during, rather than prior to, magnetic resonance imaging (MRI) has the potential to damage sensitive and expensive equipment or interfere with acquisition of MRI signal. The CPAW is a practical and effective alternative to the traditional CPT. Composed of a versatile list of inexpensive and easily acquired components, CPAW makes use of MRI-safe gelpacs cooled to a temperature similar to CPT rather than actual water. Importantly CPAW is associated with levels of SAM and HPA activation comparable to CPT, and can easily be applied in a variety of research contexts. While it is important to maintain specific safety protocols when using the technique, these are easy to implement if planned for. Creation and use of the CPAW will be discussed.

The cold pressor test is a classic stress induction task used in a wide range of research examining the relationship between stress and cognition, emotion, and behavior. In this article, a practical and versatile alternative to the traditional cold pressor test is presented: the cold pressor arm wrap.

Recently research on the relationship between stress and cognition, emotion, and behavior has greatly increased. These advances have yielded insights into ...

Mindfulness in Motion (MIM): An Onsite Mindfulness Based Intervention (MBI) for Chronically High Stress Work Environments to Increase Resiliency and Work Engagement

A pragmatic mindfulness intervention to benefit personnel working in chronically high-stress environments, delivered onsite during the workday, is timely and valuable to employee and employer alike. Mindfulness in Motion (MIM) is a Mindfulness Based Intervention (MBI) offered as a modified, less time intensive method (compared to Mindfulness-Based Stress Reduction), delivered onsite, during work, and intends to enable busy working adults to experience the benefits of mindfulness. It teaches mindful awareness principles, rehearses mindfulness as a group, emphasizes the use of gentle yoga stretches, and utilizes relaxing music in the background of both the group sessions and individual mindfulness practice. MIM is delivered in a group format, for 1 hr/week/8 weeks. CDs and a DVD are provided to facilitate individual practice. The yoga movement is emphasized in the protocol to facilitate a quieting of the mind. The music is included for participants to associate the relaxed state experienced in the group session with their individual practice. To determine the intervention feasibility/efficacy we conducted a randomized wait-list control group in Intensive Care Units (ICUs). ICUs represent a high-stress work environment where personnel experience chronic exposure to catastrophic situations as they care for seriously injured/ill patients. Despite high levels of work-related stress, few interventions have been developed and delivered onsite for such environments. The intervention is delivered on site in the ICU, during work hours, with participants receiving time release to attend sessions. The intervention is well received with 97% retention rate. Work engagement and resiliency increase significantly in the intervention group, compared to the wait-list control group, while participant respiration rates decrease significantly pre-post in 6/8 of the weekly sessions. Participants value institutional support, relaxing music, and the instructor as pivotal to program success. This provides evidence that MIM is feasible, well accepted, and can be effectively implemented in a chronically high-stress work environment.

Mindfulness in Motion MIM: An Onsite Mindfulness Based Intervention MBI for Chronically High Stress Work Environments to Increase Resiliency and Work Engagement

The Mindfulness in Motion (MIM) protocol offers a pragmatic Mindfulness Based Intervention (MBI) on-site, for persons working in chronically high-stress work environments that significantly increases resiliency and work engagement. The protocol has proven feasible, beneficial, and is easily adaptable to other high-stress workplaces.

A pragmatic mindfulness intervention to benefit personnel working in chronically high-stress environments, delivered onsite during the workday, is timely ...

The Trier Social Stress Test Protocol for Inducing Psychological Stress

This article demonstrates a psychological stress protocol for use in a laboratory setting. Protocols that allow researchers to study the biological pathways of the stress response in health and disease are fundamental to the progress of research in stress and anxiety.1 Although numerous protocols exist for inducing stress response in the laboratory, many neglect to provide a naturalistic context or to incorporate aspects of social and psychological stress. Of psychological stress protocols, meta-analysis suggests that the Trier Social Stress Test (TSST) is the most useful and appropriate standardized protocol for studies of stress hormone reactivity.2 In the original description of the TSST, researchers sought to design and evaluate a procedure capable of inducing a reliable stress response in the majority of healthy volunteers.3 These researchers found elevations in heart rate, blood pressure and several endocrine stress markers in response to the TSST (a psychological stressor) compared to a saline injection (a physical stressor).3 Although the TSST has been modified to meet the needs of various research groups, it generally consists of a waiting period upon arrival, anticipatory speech preparation, speech performance, and verbal arithmetic performance periods, followed by one or more recovery periods. The TSST requires participants to prepare and deliver a speech, and verbally respond to a challenging arithmetic problem in the presence of a socially evaluative audience.3 Social evaluation and uncontrollability have been identified as key components of stress induction by the TSST.4 In use for over a decade, the goal of the TSST is to systematically induce a stress response in order to measure differences in reactivity, anxiety and activation of the hypothalamic-pituitary-adrenal (HPA) or sympathetic-adrenal-medullary (SAM) axis during the task.1 Researchers generally assess changes in self-reported anxiety, physiological measures (e.g. heart rate), and/or neuroendocrine indices (e.g. the stress hormone cortisol) in response to the TSST. Many investigators have adopted salivary sampling for stress markers such as cortisol and alpha-amylase (a marker of autonomic nervous system activation) as an alternative to blood sampling to reduce the confounding stress of blood-collection techniques. In addition to changes experienced by an individual completing the TSST, researchers can compare changes between different treatment groups (e.g. clinical versus healthy control samples) or the effectiveness of stress-reducing interventions.1

This article describes a protocol for inducing psychological stress in participants, which enables researchers to measure psychological, physiological and neuroendocrine responses to stress within single participants or between groups.

This article demonstrates a psychological stress protocol for use in a laboratory setting.  Protocols that allow researchers to study the biological ...

Medicine

A Modified Trier Social Stress Test for Vulnerable Mexican American Adolescents

The Trier Social Stress Test (TSST) is a well validated and widely used social stressor that has been shown to induce a 2-4 fold increase in cortisol, the biological output produced by the Hypothalamic-Pituitary-Adrenal (HPA) axis in humans. While studies have explored how modifications to the TSST influence stress responsivity, few studies have created a modified TSST appropriate for vulnerable youth that elicits a significant cortisol stress response. Thus, the current study sought to modify or adjust the TSST in a culturally sensitive way for a vulnerable sample of 14 year-old adolescents. The present study took place within the context of a longitudinal birth cohort study of Mexican American families in California called the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS). The CHAMACOS sample was optimal to test the effectiveness of a modified culturally appropriate TSST, as it is comprised of Mexican American youth, who are often excluded from research. These youths also have experienced significant early life adversity. Example modifications included timed prompts, alternative math tasks, use of same-ethnicity peers as confederates, debriefing immediately after the conclusion of the TSST, and using an unknown youth examiner to administer the debrief. Saliva samples were collected at baseline (after a resting phase), and then again at 15, 30, and 45 min post-TSST onset to assess cortisol concentration. A pilot study of 50 participants (50% female) have been analyzed for cortisol reaction to the TSST. Results confirmed that this modified version of the TSST was successful at eliciting a significant cortisol reaction, with a wide range of variability likely due to individual differences. Goals for modifications and ethnicity considerations are discussed. This study provides the foundation for future research to utilize a modified TSST with vulnerable youth.

Here, we present a protocol that provoked cortisol reactivity in a vulnerable adolescent Mexican American sample utilizing a modified version of the Trier Social Stress Test (TSST). Saliva samples were collected at baseline, 15, 30, and 45 min post-TSST onset. Future research could utilize this modified TSST with vulnerable youth.

The Trier Social Stress Test (TSST) is a well validated and widely used social stressor that has been shown to induce a 2-4 fold increase in cortisol, the ...

Developmental Biology

Driving Under the Influence: How Music Listening Affects Driving Behaviors

Car driving is a daily activity for many individuals in modern societies. Drivers often listen to music while driving. The method presented here investigates how listening to music influences driving behaviors. A driving simulation was selected because it offers both a well-controlled environment and a good level of ecological validity. Driving behaviors were assessed through a car-following task. In practice, participants were instructed to follow a lead vehicle as they would do in real life. The lead vehicle speed changed over time requiring constant speed adjustments for the participants. The inter-vehicular time was used to assess driving behaviors. To complement the driving behaviors, the subjective mood and physiological level of arousal were also collected. As such, the results collected using this method offer insights on both the human internal state (i.e., subjective mood and physiological arousal) and driving behaviors in the car following task.

Here, we present a protocol to assess driving behaviors while following a vehicle in a simulated driving environment. The presented protocol is used to compare the impact of different auditory backgrounds on driving behaviors.

Car driving is a daily activity for many individuals in modern societies. Drivers often listen to music while driving. The method presented here ...

Measuring Biophysical and Psychological Stress Levels Following Visitation to Three Locations with Differing Levels of Nature

Visitation to natural environments has been linked to psychological stress reduction. Although most stress-related research has relied on self-report formats, a growing number of studies now incorporate biological stress-related hormones and catalysts, such as cortisol and &#945;-amylase, to measure levels of stress. Presented here is a protocol to examine the effects on levels of biophysical and psychological stress following visitation to three different locations with differing levels of nature. Biophysical and self-reported psychological stress levels are measured immediately upon entering the selected locations and just prior to the visitors leaving the site. Using a &#34;drool&#34;&#160;method, the biophysical measure consists of 1-2 mL samples of saliva provided by study subjects upon entry to one of three study locations. As prescribed by extant literature, the saliva is collected within a 45 minute time frame following the end of the visitor&#8217;s engagement at the location. Following saliva collection, the samples are labeled and transported to a biological lab. Cortisol is the biophysical variable of interest in this study and measured using an ELISA process with a TECAN plate reader. To measure self-reported stress, the Perceived Stress Questionnaire (PSQ), which reports levels of worry, tension, joy, and perceived demands. Data are collected at all three sites in the late afternoon through early evening. When compared across all three settings, stress levels, as measured by both the biological markers and self-reports, are significantly lower after visitation to the most natural setting.

The purpose of this paper is to identify changes in stress levels after visitation to three different settings and to describe the methods used in identifying stress levels based on measures of salivary cortisol, &#945;-amylase, and a psychological self-report instrument.&#160;

Visitation to natural environments has been linked to psychological stress reduction. Although most stress-related research has relied on self-report ...

Psychophysiological Stress Assessment Using Biofeedback 

In the last half century, research in biofeedback has shown the extent to which the human mind can influence the functioning of the autonomic nervous system, previously thought to be outside of conscious control. By letting people observe signals from their own bodies, biofeedback enables them to develop greater awareness of their physiological and psychological reactions, such as stress, and to learn to modify these reactions. Biofeedback practitioners can facilitate this process by assessing people s reactions to mildly stressful events and formulating a biofeedback-based treatment plan. During stress assessment the practitioner first records a baseline for physiological readings, and then presents the client with several mild stressors, such as a cognitive, physical and emotional stressor. Variety of stressors is presented in order to determine a person's stimulus-response specificity, or differences in each person's reaction to qualitatively different stimuli. This video will demonstrate the process of psychophysiological stress assessment using biofeedback and present general guidelines for treatment planning.

Psychophysiological Stress Assessment Using Biofeedback

In this video we will describe one method of assessing person's psychophysiological reaction to stress using biofeedback. We will also present general guidelines for treatment planning.

In the last half century, research in biofeedback has shown the extent to which the human mind can influence the functioning of the autonomic nervous ...

Biology

Modeling Social Stress

Stress negatively affects our quality of life. In particular, some individuals experience social stress when placed in a social environment that they are unfamiliar with or have difficulty adjusting to. Since it is hard to examine mechanisms of social stress in humans, modeling this condition in animals may help scientist in developing new therapies for treating this commonly encountered problem.
This science education video begins by discussing the known anatomy and physiology behind stress response. Then, we explain a well-established paradigm for modeling social stress in rodents, the Resident-Intruder task. In the applications section, we review some example studies in which response to stress is measured.

Physiology of Stress; Social Stress- Resident-Intruder Task

Stress negatively affects our quality of life. In particular, some individuals experience social stress when placed in a social environment that they are ...

JoVE Science Education

Psychology

Behavioral Science

Introduction to Stress and Lifestyle

Stress is a multifaceted response to events perceived as challenging or threatening, highlighting physical, emotional, cognitive, and behavioral reactions. Physically, stress can lead to fatigue, sleep disruptions, and various health issues such as frequent colds, chest pains, and nausea. Emotionally, it can manifest as anxiety, depression, irritability, and anger triggered by both minor and major life events. Cognitively, it may result in difficulty in concentration, memory, and decision-making, and individuals often lose their sense of humor. Behaviorally, it can lead to overeating or increased emotional reactivity, such as crying. A particularly severe stressor, known as a traumatic event, can have long-term psychological and health consequences.
Stress can be categorized into two types: distress and eustress. Distress arises from unpleasant stressors, such as job loss and relationship conflicts. At the same time, eustress stems from positive events that require adaptation, such as marriage, a job promotion, or the birth of a child. Even though these events are often seen as positive, they can still cause stress due to the significant lifestyle changes they demand. For example, while the birth of a baby is a joyous event, it can also lead to concerns about the child&#39;s health, contributing to stress. Research indicates that women who are highly anxious or experience negative life events during pregnancy have an increased risk of premature delivery compared to those with lower stress levels.
Researchers approach stress in three complementary ways:
<ol>
	<li>Stress as stimulus: This focuses on identifying external stressors, such as life events like job loss or illness, that cause stress.</li>
	<li>Stress as a response: This examines the psychological and physical reactions individuals have to stress, including emotional and physiological responses like anxiety or elevated heart rate.</li>
	<li>Stress as a transaction: This approach looks at the dynamic interaction between stressful events and how individuals perceive, evaluate, and cope with them, emphasizing personal interpretation and coping mechanisms.</li>
</ol>
The study of stress often involves examining the outcomes of exposure to stressful stimuli, whether in laboratory settings or real-world scenarios. Scientists measure variables such as emotional responses (e.g., depression and hostility) and physiological markers, including elevated heart rates and the release of corticosteroids. Interestingly, highly stressful events, such as natural disasters, can sometimes lead to posttraumatic growth, where individuals report personal growth and positive change following adversity. Stress responses are highly individual, with people reacting differently to the same life events depending on how they interpret and cope with them.

Stress refers to the physical, emotional, cognitive, and behavioral reactions to events perceived as threatening or challenging.
Physically, it can cause ...

KEY TERMS AND CONCEPTS

Types of Stressors

A stressor is any event, condition, or stimulus that triggers stress and causes a physical or psychological response in the body. Stressors can be categorized into three main types: catastrophes; significant life changes; and daily hassles, including social stress. Each can be detrimental to physical and mental well-being.
Catastrophes 
Catastrophes refer to large-scale, unpredictable events that create overwhelming stress and a sense of threat. Examples include natural disasters like earthquakes, tornadoes, and hurricanes, as well as human-made disasters such as wars. These events not only cause immediate physical harm but also result in long-lasting emotional and psychological damage. For individuals displaced by catastrophes, such as those forced to emigrate, the stress is compounded by the challenges of adjusting to a new cultural environment, which may involve language barriers, climate adaptation, and social integration issues.
Significant Life Changes 
Major life transitions also contribute significantly to stress. Events such as marriage, divorce, job loss, or the death of a loved one demand substantial emotional adjustment. Even positive changes can be sources of stress; graduating or moving to a new city can be sources of stress, as they often require new routines, responsibilities, and adaptations. Coping with these changes plays a central role in the stress experience, as they disrupt an individual&#39;s normal state of equilibrium.
Daily Hassles and Social Stress 
While major events contribute to long-term stress, daily hassles often have a more immediate impact. Minor frustrations &#8212; traffic jams, social media overload, or interpersonal conflicts &#8212; may seem trivial but can accumulate to affect overall health. Daily stressors are closely linked to short-term ailments such as headaches, colds, and muscle tension, reflecting their direct impact on well-being.
Likewise, social stress, arising from frequent social interactions and constant social media notifications, can amplify daily frustrations and negatively impact overall well-being. This type of stress is linked to the pressure to respond, keep up with information, and manage relationships online, which can lead to feelings of anxiety, overwhelm, and mental fatigue. Over time, this continuous exposure to social demands can contribute to stress-related issues like burnout, sleep problems, and lower emotional resilience.

Stressors refer to events that cause stress and can be grouped into three main categories: catastrophes, significant life changes, and daily hassles, ...

Assessing the Effects of Music Listening on Psychobiological Stress in Daily Life

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