This study was supported by National Natural Science Foundation for Young Scientists of China (No.81902281); General Guidance Project of Guangzhou Health and Family Planning Commission (No.20191A0011091 and 20201A011108), Guangdong Provincial Department of Education (No. 2019KQNCX119) and Guangzhou Key Laboratory Fund (No.201905010004). This study also thanks Lixin Zhang, Peilin Ruan, Kaihang Ji, and Gulifeiya Tuerxun from Guangzhou Medical University for data collection.

The clinical project was approved by the Medical Ethics Association of the Fifth Affiliated Hospital of Guangzhou Medical University (No. KY01-2020-06-06) and has been registered at the China Clinical Trial Registration Center (No. ChiCTR2000033449) and entitled &#34;The effects of masks on cardiopulmonary and lower limb function&#34;.
1. Participant recruitment
<ol>
	<li>Include subjects between 18 and 26 years old: who can pass the PAR-Q test6; are physically healthy; without professional sports training experience; and able to understand the experiment and voluntarily cooperate with the whole test process.</li>
	<li>Exclude subjects: with cardiovascular diseases and respiratory diseases; with lower limb motor dysfunction caused by other diseases; who cannot cooperate with the experiment; and smokers7.</li>
	<li>Obtain written informed consent from each subject before their participation.</li>
	<li>Inform the subject that strenuous activities are prohibited 48 h before the test and during the test, and that food and beverages (except water) are not allowed 2 h before the test.</li>
	<li>Collect the subjects&#39; basic information (name, gender, date of birth, height, weight).</li>
	<li>Randomly allocate the subjects into two groups by SPSS generated digit table. Group 1 first received CPET in the mask-on condition followed by 48 h of washout, and then received CPET in the mask-off condition. Group 2 first received CPET in the mask-off condition followed by 48 h of washout, then received CPET in the mask-on condition.</li>
</ol>
2. Laboratory settings and equipment preparation
<ol>
	<li>Set the laboratory temperature to 25 &#176;C and equip with first aid equipment.</li>
	<li>Calibrate the cardiopulmonary function analyzer to ensure the accuracy of the CPET test, including flow sensor calibration, indoor air calibration, gas analysis calibration, and respiratory rate calibration. 
	&#8203;NOTE: For gas analysis calibration, use 5% CO2 and 16% O2 concentrations and N2 for balance.</li>
</ol>
3. Spirometry
<ol>
	<li>Ask the subject to sit upright without leaning on the back of the chair, with their feet on the ground, but without tilting their feet. Ask them to keep their head at a natural level or slightly tilted upwards, but not to bend their head down or bend over.</li>
	<li>Forced Vital Capacity (FVC) test: Ask the subject to breathe calmly for 5 s, inhale strongly, and then exhale strongly for 6 s. Finally, inhale back and keep breathing calmly. Perform the whole procedure under the guidance of a doctor or a formally trained exercise physiologist.</li>
	<li>Maximum Voluntary Ventilation (MVV) test: Ask the subject to breathe calmly four or five times. Then repeat the breath continuously for 12 s or 15 s at the maximum breathing amplitude and the fastest breathing speed after the baseline with expiratory volume is stable (Figure 1). 
	&#8203;NOTE: If the subject does not perform well during static lung function test, the subject will be asked to perform the tests one more time after a 3-min rest. If the subject fails the test twice, exclude the subject.</li>
</ol>
4. Cardiopulmonary exercise test (CPET)
<ol>
	<li>Subject preparation for CPET
	<ol>
		<li>Briefly introduce the process to the subject.</li>
		<li>Scrape the body hair at the position of the electrocardiograph (ECG) electrodes (V1 to V6), and then use 75% alcohol to remove extra dander and grease. 
		&#8203;NOTE: V1 is the 4th intercostal space to the right of the sternum. V2 is the 4th intercostal space, to the left of the sternum, V3 is between V2 and V4 electrodes, V4 is the 5th intercostal space on the midclavicular line, V5 is the 5th intercostal space, on the anterior axillary line, and V6 is the 5th intercostal space on the left midaxillary line. Place limb electrodes for the arms in the sub-clavicular areas, and place limb electrodes for the legs placed on the trunk at the level of the bottom rib. The electrode placement should be lateral to avoid excessive movement artifact during cycling.</li>
		<li>Place the ECG electrodes and attach them to the 12-lead ECG wires.</li>
		<li>Fix the ECG machine to the chest using a strap (Figure 2).</li>
		<li>Choose a mask that fits the size of the subject&#39;s face and attach it firmly to the face to ensure that there is no gap between the mask and the face (Figure 3). 
		NOTE: The tester could use their hand to press gently on the vest and lightly exhale to ensure that there is no gap.</li>
		<li>Fix the flow meter on the vent and then fix the K4 device onto the vest (Figure 4).</li>
		<li>Sit on the seat and adjust the height of the handlebars to a comfortable position for the subject.</li>
		<li>Grab the handlebar with both hands and step on the pedals with bilateral feet to ensure that the right knee joint bends with flexion at 30&#176;.</li>
		<li>Place a blood pressure cuff on the upper-right arm for dynamic blood pressure recording. Place a finger pulse oxygen on the left index finger for dynamic recording of blood oxygen.</li>
		<li>Calculate the subject&#39;s exercise resistance/increased incremental per min (W) parameters and set the progressive resistance plan for the exercise phase8. 
		NOTE: Exercise resistance (male) = [(height - age) * 20 - (150 + 6 * weight)] / 100 
		Exercise resistance (female) = [(height - age) * 14 - (150 + 6 * weight)] / 100</li>
	</ol>
	</li>
	<li>CPET executing phase 
	&#8203;NOTE: Ask the subject not to speak during the whole procedure to prevent extra exhalation and inhalation during speaking, which might affect the accuracy of the cardiopulmonary data. Ask the subject to please raise their hand to indicate if there is any questions or discomfort that results in the test interruption.
	<ol>
		<li>Click on the Start button to activate cycle ergometer by tester.</li>
		<li>Keep a static sitting posture for 2 min (Rest stage).</li>
		<li>Start cycling for 2 min (Warm-up stage: resistance to 0 W, speed to 60 rpm).</li>
		<li>Continue cycling until the time point when the subject could not maintain or show the ending signs (Ramp exercise stage: Incremental resistance, X watt resistance per min, 60 rpm). 
		&#8203;NOTE: X watt resistance per min is based on the formulas in step 4.1.10.</li>
		<li>Ask the subject to cycle for 3 min (cool-down stage: resistance to 0 W, speed to 40 rpm).</li>
		<li>Keep the static sitting posture for 3 min for observation of vital signs (observation stage). 
		&#8203;NOTE: Criteria for discontinuing are as follows: Subjects are encouraged to exercise to their maximum endurance or until the practitioners end the exercise due to symptoms such as ischemic ECG changes, complex ectopy, second or third degree heart block, fall in systolic pressure &#62;20 mm Hg from the highest value during the test, hypertension (&#62;250 mm Hg systolic; &#62;120 mm Hg diastolic), severe desaturation (oxyhemoglobin saturation (SpO2) &#8804; 80%), symptoms and signs of severe hypoxemia (sudden pallor, loss of coordination, mental confusion, dizziness, faintness), signs of respiratory failure, or exhaustion (Borg &#8805; 17-18 points) failed maintaining the cycling speed (lower than 40 rpm). The test will be terminated immediately if the subjects show extreme verbal or physical fatigue7, which is lower than 40 rpm.</li>
		<li>Remove data acquisition equipment, face mask, vest, and ECG electrodes.</li>
	</ol>
	</li>
</ol>
5. CPET post testing
<ol>
	<li>Use the Rating of Perceived Exertion (RPE) scale to measure physical activity intensity levels that are apparently related to the heart rate (HR) during exercise9,10.</li>
	<li>Use the Borg&#39;s scale (6-20 scale) to evaluate exertion of resistance training 11. A score of 6 represents resting activity with no effort and a score of 20 represents exhaustive exercise.</li>
</ol>
6. Statistical analysis
<ol>
	<li>Analyze the data using SPSS software (version 25) and the methodology referenced in the previous study12.</li>
	<li>Present the parametric data as mean and standard deviation (SD) if normally distributed or median if not.</li>
	<li>Allocate the subjects into male or female groups for statistical analysis, respectively.</li>
	<li>Use the paired t-test to compare the differences of CPET parameters between subjects in the mask-on condition and mask-off condition. Statistical significance is P &#60; 0.05.</li>
</ol>

<ol>
	<li>Davies, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testing+the+Efficacy+of+Homemade+Masks:+Would+They+Protect+in+an+Influenza+Pandemic.">Testing the Efficacy of Homemade Masks: Would They Protect in an Influenza Pandemic.</a> Disaster Medicine and Public Health Preparedness. 7 (4), 413-418 (2013).</li><li>Fikenzer, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+surgical+and+FFP2/N95+face+masks+on+cardiopulmonary+exercise+capacity.">Effects of surgical and FFP2/N95 face masks on cardiopulmonary exercise capacity.</a> Clinical Research in Cardiology. , (2020).</li><li>MacIntyre, C. R., Chughtai, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+rapid+systematic+review+of+the+efficacy+of+face+masks+and+respirators+against+coronaviruses+and+other+respiratory+transmissible+viruses+for+the+community,+healthcare+workers+and+sick+patients.">A rapid systematic review of the efficacy of face masks and respirators against coronaviruses and other respiratory transmissible viruses for the community, healthcare workers and sick patients.</a> International Journal of Nursing Studies. 108, 103629 (2020).</li><li>Esposito, S., Principi, N., Leung, C. C., Migliori, G. 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The authors have nothing to disclose.

CPET provides valuable insights into the comprehensive functions of cardiovascular, ventilation, and skeletal muscle systems13. We proposed a CPET protocol on mask-on and mask-off conditions to explore the effect of the surgical mask on the cardiopulmonary function in healthy young subjects.
The design of this protocol was based on three main points. First, we recruited young healthy college students as the subjects for the study due to relatively high intensityof CPET ...

Wearing a face mask in public areas might impede the spread of an infectious disease by preventing both the inhalation of infectious droplets and their subsequent exhalation and dissemination1. Although the effect of reducing the risk of transmission of respiratory viruses remains controversial, wearing masks remains one of the major ways people in the community have chosen to prevent the spread of droplets among individuals in daily life2,3,4.
Different types of masks have different effects on increasing expiratory resistance and inspiratory resistance5. Meanwhile, during a respiratory disease pandemic, people (including healthy people and patients with cardiopulmonary diseases) might need to wear masks for a long time to perform daily activities. However, there are few studies on the effect of wearing a mask on cardiopulmonary function.
Cardiopulmonary exercise testing (CPET) is an important means of cardiovascular rehabilitation risk assessment by reflecting various parameters of the body&#39;s cardiopulmonary function during exercise with increasing load and is considered to be the gold standard for cardiopulmonary reserve testing2. We use CPET under different conditions (mask-on and mask-off) to study the changes in cardiopulmonary function parameters of healthy young subjects, to evaluate the interference of masks objectively and quantitatively on cardiorespiratory reserve and exercise endurance from a novel methodological perspective to guide the application of masks in particular respiratory infectious disease pandemic. Although FFP2/N95 has been suggested to be more efficacious than surgical masks at reducing exposure to viral infections, medical-surgical masks are more convenient and common to obtain and use than FFP2/N95 face masks. Thus, this study focuses only on the effects of medical surgical masks on cardiopulmonary function.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Cardiopulmonary test system</td>
			<td>COSMED Srl - Italy</td>
			<td>K4b2</td>
			<td>Pulmonary Function Equipment</td>
		</tr>
		<tr>
			<td>Cycle for CPET</td>
			<td>COSMED Srl - Italy</td>
			<td>ergoline 100P</td>
			<td>cycle ergometer 100 P w/BP</td>
		</tr>
		<tr>
			<td>Eectrocardiograph&#160;</td>
			<td>COSMED Srl - Italy</td>
			<td>Quark T12x</td>
			<td>12-Channel ECG Street Test Unit</td>
		</tr>
		<tr>
			<td>Mask</td>
			<td>COSMED Srl - Italy</td>
			<td>Small,Medium,Large</td>
			<td>V2 Mask</td>
		</tr>
		<tr>
			<td>Software</td>
			<td>COSMED Srl - Italy</td>
			<td>PFT SUITE</td>
			<td>PC Software</td>
		</tr>
		<tr>
			<td>Surgical masks</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

effects of surgical masks on cardiopulmonary function in healthy subjects

We study the effect of surgical masks on cardiopulmonary function based on a cardiopulmonary exercise test (CPET). This study shows that surgical masks reduce cardiopulmonary exercise capacity and ventilation in healthy young subjects and wearing masks might affect aerobic exercise capacity more in female subjects than in male subjects.

Ten subjects (five males and five females) from the Department of Rehabilitation Medicine at Guangzhou Medical University were recruited in this pilot study. The participants had similar baseline characteristics, such as age (mean age: male 21.00 &#177; 1.58 years; female 21.20 &#177; 0.45 years) and physical fitness [sports activity and body mass index (BMI)]. There were no significant differences in age, height, or BMI between the male and female groups. Moreover, for the spirometry, th...

Watch this Scientific Journal Video about Effects of Surgical Masks on Cardiopulmonary Function in Healthy Subjects at JoVE.com

Effects of Surgical Masks on Cardiopulmonary Function in Healthy Subjects

We study the effect of surgical masks on cardiopulmonary function based on a cardiopulmonary exercise test (CPET). This study shows that surgical masks reduce cardiopulmonary exercise capacity and ventilation in healthy young subjects and wearing masks might affect aerobic exercise capacity more in female subjects than in male subjects.

We study the effect of surgical masks on cardiopulmonary function based on a cardiopulmonary exercise test (CPET). This study shows that surgical masks ...

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3.1K Views.  The Fifth Affiliated Hospital of Guangzhou Medical University. We study the effect of surgical masks on cardiopulmonary function based on a cardiopulmonary exercise test (CPET). This study shows that surgical masks reduce cardiopulmonary exercise capacity and ventilation in healthy young subjects and wearing masks might affect aerobic exercise capacity more in female subjects than in male subjects.

Video: Effects of Surgical Masks on Cardiopulmonary Function in Healthy Subjects

Performing Behavioral Tasks in Subjects with Intracranial Electrodes

Patients having stereo-electroencephalography (SEEG) electrode, subdural grid or depth electrode implants have a multitude of electrodes implanted in different areas of their brain for the localization of their seizure focus and eloquent areas. After implantation, the patient must remain in the hospital until the pathological area of brain is found and possibly resected. During this time, these patients offer a unique opportunity to the research community because any number of behavioral paradigms can be performed to uncover the neural correlates that guide behavior. Here we present a method for recording brain activity from intracranial implants as subjects perform a behavioral task designed to assess decision-making and reward encoding. All electrophysiological data from the intracranial electrodes are recorded during the behavioral task, allowing for the examination of the many brain areas involved in a single function at time scales relevant to behavior. Moreover, and unlike animal studies, human patients can learn a wide variety of behavioral tasks quickly, allowing for the ability to perform more than one task in the same subject or for performing controls. Despite the many advantages of this technique for understanding human brain function, there are also methodological limitations that we discuss, including environmental factors, analgesic effects, time constraints and recordings from diseased tissue. This method may be easily implemented by any institution that performs intracranial assessments; providing the opportunity to directly examine human brain function during behavior.

Patients implanted with intracranial electrodes provide a unique opportunity to record neurological data from multiple areas of the brain while the patient performs behavioral tasks. Here, we present a method of recording from implanted patients that can be reproducible at other institutions with access to this patient population.

Patients having stereo-electroencephalography (SEEG) electrode, subdural grid or depth electrode implants have a multitude of electrodes implanted in ...

Investigating the Effects of Antipsychotics and Schizotypy on the N400 Using Event-Related Potentials and Semantic Categorization

Within the field of cognitive neuroscience, functional magnetic resonance imaging (fMRI) is a popular method of visualizing brain function. This is in part because of its excellent spatial resolution, which allows researchers to identify brain areas associated with specific cognitive processes. However, in the quest to localize brain functions, it is relevant to note that many cognitive, sensory, and motor processes have temporal distinctions that are imperative to capture, an aspect that is left unfulfilled by fMRI&#8217;s suboptimal temporal resolution. To better understand cognitive processes, it is thus advantageous to utilize event-related potential (ERP) recording as a method of gathering information about the brain. Some of its advantages include its fantastic temporal resolution, which gives researchers the ability to follow the activity of the brain down to the millisecond. It also directly indexes both excitatory and inhibitory post-synaptic potentials by which most brain computations are performed. This sits in contrast to fMRI, which captures an index of metabolic activity. Further, the non-invasive ERP method does not require a contrast condition: raw ERPs can be examined for just one experimental condition, a distinction from fMRI where control conditions must be subtracted from the experimental condition, leading to uncertainty in associating observations with experimental or contrast conditions. While it is limited by its poor spatial and subcortical activity resolution, ERP recordings&#8217; utility, relative cost-effectiveness, and associated advantages offer strong rationale for its use in cognitive neuroscience to track rapid temporal changes in neural activity. In an effort to foster increase in its use as a research imaging method, and to ensure proper and accurate data collection, the present article will outline &#8211; in the framework of a paradigm using semantic categorization to examine the effects of antipsychotics and schizotypy on the N400 &#8211; the procedure and key aspects associated with ERP data acquisition.

Using event-related EEG potentials (ERPs), we investigate the effects of antipsychotic medications on abnormal semantic brain activations in healthy individuals with schizotypal traits. We use ERPs to track distinct changes in brain activity, shedding insight into the cognitive processes associated with semantic categorization.

Within the field of cognitive neuroscience, functional magnetic resonance imaging (fMRI) is a popular method of visualizing brain function. This is in ...

How to Study Placebo Responses in Motion Sickness with a Rotation Chair Paradigm in Healthy Participants

Placebo responses occur in every medical intervention when patients or participants expect to receive an effective treatment to relieve symptoms. However, underlying mechanisms of placebo responses are not fully understood. It has repeatedly been shown that placebo responses are associated with changes in neural activity but for many conditions it is unclear whether they also affect the target organ, such as the stomach in motion sickness. Therefore, we present a methodology for the multivariate assessment of placebo responses by subjective, behavioral and objective measures in motion sickness with a rotation chair paradigm. The physiological correlate of motion sickness is a shift in gastric myoelectrical activity towards tachygastria that can be recorded with electrogastrography. The presented study applied the so-called balanced placebo design (BPD) to investigate the effects of ginger compared to placebo and the effects of expectations by verbal information. However, the study revealed no significant main or interactional effects of ginger (as a drug) or information on outcome measures but showed interactions when sex of participants and experimenters are taken into considerations. We discuss limitations of the presented study and report modifications that were used in subsequent studies demonstrating placebo responses when rotation speed was lowered. In general, future placebo studies have to identify the appropriate target organ for the studied placebo responses and to apply the specific methods to assess the physiological correlates.

An experimental rotation chair paradigm is used to investigate whether a placebo intervention on motion sickness affects subjective outcome measures only or also affects behavioral and objective measures in a balanced placebo design.

Placebo responses occur in every medical intervention when patients or participants expect to receive an effective treatment to relieve symptoms. However, ...

Applying Stereotactic Injection Technique to Study Genetic Effects on Animal Behaviors

Stereotactic injection is a useful technique to deliver high titer lentiviruses to targeted brain areas in mice. Lentiviruses can either overexpress or knockdown gene expression in a relatively focused region without significant damage to the brain tissue. After recovery, the injected mouse can be tested on various behavioral tasks such as the Open Field Test (OFT) and the Forced Swim Test (FST). The OFT is designed to assess locomotion and the anxious phenotype in mice by measuring the amount of time that a mouse spends in the center of a novel open field. A more anxious mouse will spend significantly less time in the center of the novel field compared to controls. The FST assesses the anti-depressive phenotype by quantifying the amount of time that mice spend immobile when placed into a bucket of water. A mouse with an anti-depressive phenotype will spend significantly less time immobile compared to control animals. The goal of this protocol is to use the stereotactic injection of a lentivirus in conjunction with behavioral tests to assess how genetic factors modulate animal behaviors.

Stereotactic injection of lentiviruses expressing cDNAs or shRNAs can modulate gene expression in specific brain areas of mice. Here, we present a protocol to combine stereotactic injections with behavioral tasks, such as the Open Field Test (OFT) and the Forced Swim Test (FST).

Stereotactic injection is a useful technique to deliver high titer lentiviruses to targeted brain areas in mice. Lentiviruses can either overexpress or ...

Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects

Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about mechanosensory function that are relevant for clinical diagnosis as well as for basic research. Here, we describe two psychophysical tests designed to determine the vibration detection threshold (automated system) and tactile spatial acuity (handheld device). Both procedures implement a two-interval forced-choice and a transformed-rule up and down experimental paradigm. These tests have been used to obtain mechanosensory profiles for individuals from distinct human cohorts such as twins or people with sensorineural deafness.

Here, we present protocols to determine vibration detection thresholds and tactile acuity using psychophysical methods in man.

Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about ...

A General Method for Evaluating Deep Brain Stimulation Effects on Intravenous Methamphetamine Self-Administration

Substance use disorders, particularly to methamphetamine, are devastating, relapsing diseases that disproportionally affect young people. There is a need for novel, effective and practical treatment strategies that are validated in animal models. Neuromodulation, including deep brain stimulation (DBS) therapy, refers to the use of electricity to influence pathological neuronal activity and has shown promise for psychiatric disorders, including drug dependence. DBS in clinical practice involves the continuous delivery of stimulation into brain structures using an implantable pacemaker-like system that is programmed externally by a physician to alleviate symptoms. This treatment will be limited in methamphetamine users due to challenging psychosocial situations. Electrical treatments that can be delivered intermittently, non-invasively and remotely from the drug-use setting will be more realistic. This article describes the delivery of intracranial electrical stimulation that is temporally and spatially separate from the drug-use environment for the treatment of IV methamphetamine dependence. Methamphetamine dependence is rapidly developed in rodents using an operant paradigm of intravenous (IV) self-administration that incorporates a period of extended access to drug and demonstrates both escalation of use and high motivation to obtain drug.

This article describes the delivery of intracranial electrical stimulation that is temporally and spatially separate from the drug-use environment for the treatment of IV methamphetamine dependence.

Substance use disorders, particularly to methamphetamine, are devastating, relapsing diseases that disproportionally affect young people.  There is a need ...

Behavioral Disturbances: An Innovative Approach to Monitor the Modulatory Effects of a Nutraceutical Diet

In dogs, diets are often used to modulate behavioral disturbances related to chronic anxiety and stress caused by intense and restless activity. However, the traditional ways to monitor behavioral changes in dogs are complicated and not efficient. In the current clinical evaluation, a new, simple monitoring system was used to assess the effectiveness of a specific diet in positively modulating the intense and restless activity of 24 dogs of different ages and breeds. This protocol describes how to easily and rapidly evaluate improvement in a set of symptoms related to generalized anxiety by using a specific sensor, a mobile phone app, a wireless router, and a computer. The results showed that dogs treated with specific diets showed significant improvement in the times spent active and at rest after 10 days (p &lt; 0.01 and p &lt; 0.05, respectively). These dogs also showed an overall significant improvement in clinical and behavioral symptoms. A specific sensor, along with its related hardware, was demonstrated to successfully monitor behavioral changes relating to movement in dogs.

We report a simple approach to evaluate the effectiveness of a specific diet in positively modulating the daily activity and clinical and behavioral symptoms of dogs with evident behavioral disturbances.

In dogs, diets are often used to modulate behavioral disturbances related to chronic anxiety and stress caused by intense and restless activity. However, ...

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.

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 ...

A Within-subjects Experimental Protocol to Assess the Effects of Social Input on Infant EEG

Despite the importance of social interactions for infant brain development, little research has assessed functional neural activation while infants socially interact. Electroencephalography (EEG) power is an advantageous technique to assess infant functional neural activation. However, many studies record infant EEG only during one baseline condition. This protocol describes a paradigm that is designed to comprehensively assess infant EEG activity in both social and nonsocial contexts as well as tease apart how different types of social inputs differentially relate to infant EEG. The within-subjects paradigm includes four controlled conditions. In the nonsocial condition, infants view objects on computer screens. The joint attention condition involves an experimenter directing the infant's attention to pictures. The joint attention condition includes three types of social input: language, face-to-face interaction, and the presence of joint attention. Differences in infant EEG between the nonsocial and joint attention conditions could be due to any of these three types of input. Therefore, two additional conditions (one with language input while the experimenter is hidden behind a screen and one with face-to-face interaction) were included to assess the driving contextual factors in patterns of infant neural activation. Representative results demonstrate that infant EEG power varied by condition, both overall and differentially by brain region, supporting the functional nature of infant EEG power. This technique is advantageous in that it includes conditions that are clearly social or nonsocial and allows for examination of how specific types of social input relate to EEG power. This paradigm can be used to assess how individual differences in age, affect, socioeconomic status, and parent-infant interaction quality relate to the development of the social brain. Based on the demonstrated functional nature of infant EEG power, future studies should consider the role of EEG recording context and design conditions that are clearly social or nonsocial.

This novel protocol is designed to assess the neural bases of social interaction in infants. The paradigm is designed to tease apart how various social inputs such as language, joint attention, and face-to-face interaction relate to infant neural activation. Infant EEG power is recorded during both social and nonsocial conditions.

Despite the importance of social interactions for infant brain development, little research has assessed functional neural activation while infants ...

Noninvasive, High-throughput Determination of Sleep Duration in Rodents

Traditionally, sleep is monitored by an electroencephalogram (EEG). EEG studies in rodents require surgical implantation of the electrodes followed by a long recovery period. To perform an EEG recording, the animal is connected to a receiver, creating an unnatural tether to the head-mount. EEG monitoring is time consuming, carries risk to the animal, and is not a completely natural setting for the measurement of sleep. Alternative methods to detect sleep, particularly in a high-throughput fashion, would greatly advance the field of sleep research. Here, we describe a validated method for detecting sleep via activity-based home-cage monitoring. Previous studies have shown that sleep assessed via this method has a high degree of agreement with sleep defined by traditional EEG-based measures. Whereas this method is validated for total sleep time, it is important to note that sleep bout duration should be assessed by an EEG which has better temporal resolution. The EEG can also differentiate rapid eye movement (REM) and non-REM sleep, giving more detail about the exact nature of sleep. Nevertheless, activity-based sleep determination can be used to analyze multiple days of undisturbed sleep and to assess sleep as a response to an acute event (like stress). Here, we show the power of this system to detect the response of mice to daily intraperitoneal injections.

We describe a high-throughput method of measuring sleep by means of activity-based home-cage monitoring. This method offers advantages over traditional EEG-based methods. It is well validated for the determination of total sleep duration and can be a powerful tool to monitor sleep in rodent models of human disease.

Traditionally, sleep is monitored by an electroencephalogram (EEG). EEG studies in rodents require surgical implantation of the electrodes followed by a ...