Gauging the effectiveness of music and yoga for reducing stress among engineering students: An investigation based on Galvanic Skin Response

Abstract

BACKGROUND:

The purpose of this research is to examine the influence of music and yogic breathing for the management and control of stress.

OBJECTIVE:

To discover the most effective stimuli to handle stress by measuring the effect of types of musical drills and yogic breathing on engineering students using the Galvanic Skin Response Sensor Meter (GSRSM).

METHODS:

The present study attempts to study the effectiveness of music and yoga drills for relieving and managing stress. The study used a stratified random sampling method selecting engineering students from four streams. The GSRSM was used as a tool to record the responses after 300 seconds for the experimental and the control groups of 200 students each. Each group was comprised of 52 females (26%) and 148 males (74%).

RESULTS:

The experimental group reported reduction in mean value in Galvanic Skin Response (GSR) when they underwent deep yogic breathing, listened to religious hymns and listened to flute music.

CONCLUSION:

On the basis of the results, the researchers suggest that all three techniques i.e practicing yogic breathing, listening to religious hymns and listening to flute music were effective in reducing the stress level of engineering students. Listening to flute music emerged from these three drills, as the most effective stimulus for stress management.

Keywords

Yogic breathing managing stress GSR sensor meter skin conductivity

1 Introduction

Stress is defined as “pressure or worry caused by problems in somebody’s life” [1]. Stress is experienced in different phases of life. Stress induces change in a variety of physiological responses [2]. Severe stress can harm the cell communication in the brain’s learning and memory section [3]. Sarkamo Teppo (2008) reported that stress leads to cognitive disorders [4]. Mizoguchi et al. (2000) opined that stress affects memory [5]. Stress and stress management have attracted attention of researchers across the globe. The new advancements in our society, workload, peer pressure, high-end goals, and unlimited human desires have created a sense of conflict and constant fury in our minds. This has led to increasing levels of stress. Focus on productivity and increased competitiveness have further aggravated the situation.

1.1 Music

Historical evidence supports that a combination of music and medicine can help cure certain diseases and disorders [6]. The classical music was recognized around the 11^th century and gained popularity due to the systematic notation system. Music is a dominant mood enhancer. Classical music greatly affects brain activity. It has a positive influence on the hormone system and is recognized for its relaxing effect. Trappe (2010) found patients with anxiety, pain, stress, depressive syndromes, and sleeplessness experienced relief while listening to classical music. Exposure to music reduced blood pressure and heart rate [7]. This study also suggests that hip-hop and rap music which are associated with fast tempos increased blood pressure and heart rate, causing negative influence on patients. Iwanaga and Youko (1999) showed listening to music reduced patients’ pre-surgery anxiety, measured by systolic blood pressure and heart rate [8]. Different types of music with fast or slow tempo have different effects on physiological measurements. The researchers in the present study used flute music as a music audio stimulus. The other two drills for comparisons are listening to religious hymns and yogic breathing.

Music and yoga play vital roles as stress coping strategies. Listening to music triggers development of cognitive and emotional components. The calming effect of music is well-established. College life is a stressful time for many students as they adapt to new educational and social environments. The educational system is mechanical and fails to nurture an all-round development of the personality of the students. Misra et al. (2004) found important differences in perceptions of academic stressors and reactions to these stressors amongst student participants [9]. The belief in the power of music is universal. Music is identified with recreational beliefs and has been used for prayers. Shamans, philosophers, and mystics have recognized music for its balancing, unifying and healing effects. Neuroscientists have considered the interaction of music with cognition, emotion, and physical phenomena. Zatorre and McGill (2005) examined the ways in which music may affect brain structure configuration [10]. Using medical data and equipment, Gaser and Schlaug (2003) demonstrated physical differences in the structure of the brains of musicians and non-musicians [11]. Researchers have suggested that music can have a profound effect on both the emotions and the body. Music can relax the muscles, making a person feel soothed while releasing the stress. Thus, music is effective for relaxation and stress management. Researchers have suggested yogic exercises can be used to reduce stress.

1.2 Yogic breathing

It is done by contracting the diaphragm (a muscle located horizontally between the chest cavity and stomach cavity). Air enters the lungs and the belly expands during deep breathing. Yogic breathing, also known as abdominal breathing or deep breathing, is marked by expansion of the abdomen rather than the chest during breathing. It is considered as a healthier way to breathe and is a useful form of complementary and alternative treatment. Yogic Breathing is a natural painkiller, improves blood flow, increases energy level, improves posture, reduces inflammation and improves digestion [12, 13].

2 Methods

2.1 Galvanic Skin Response (GSR) methods

Galvanic Skin Response (GSR) is a psycho-physiological phenomenon exhibited by skin containing sweat glands [14, 15]. GSR is the change in the electrical properties of the skin. The signal can be used for capturing the autonomic nerve responses as a parameter of the sweat gland function. The behavior of the autonomic nervous system (ANS) can be gauged from the signal. The measurement is relatively simple; therefore, the GSR measurement was considered for examination of the autonomous nervous system function, and especially, the peripheral sympathetic system. GSR feedback has been used in the treatment of excessive sweating (Hyperhidrosis) and related dermatological conditions. Researchers have used it for relaxation and desensitization training. The activity of the sweat glands to sympathetic nervous stimulation (increased sympathetic activation) results in boosting the level of GSR [16]. Das & Anand (2012) demonstrated a significant effect on GSR values through meditation [17]. The GSR value reduced with meditation reflecting a decreased level of stress among individuals. In the current study, GSR is used to measure stress levels before and after the drills.

2.2 Selection of population

Engineering students were selected as the study population because many earlier studies suggest they experience high academic and personal stress.

The study used a private institute and a government institute. The students were chosen from electrical engineering, civil engineering, mechanical engineering, and computer engineering. The study was executed in two phases (explained in detail in the subsequent section).

2.3 Participants

Four-hundred engineering students were selected from “private institute and a government institute.” The students were chosen from electrical engineering, civil engineering, mechanical engineering, and computer engineering.” Of these, 74% were male and 26% female. The mean age was 20.4 (SD = 1.21). Seventy-five per cent were from nuclear families (single), with 72.75% being of Hindu Religion, 27% Sikh and 0.25% of other religions. The initial screening for selecting candidates was done on the basis of a structured questionnaire. The questionnaire had questions about academic stress, financial stress, and personal stress. The students were screened and short-listed on the basis of self-observation of reporting stress.

2.4 Sample size determination

The present study covered four engineering streams from two different universities. The present study used the following formula to arrive at appropriate sample size (Scott, 2013): [18] $n = (z^{2} * σ^{2}) / (ME)^{2}$

Where n = sample size, z = standard normal random variate (z score), σ= variance

M.E. = margin of error

At 95% level of confidence n is found to be 246, taking this formula into consideration, a sample of 471 responses was targeted. The final sample size comprised of 400 valid responses (after rejecting the unfilled/impure responses).

3 Procedure

The students were interviewed. From the initial 471 students, 400 were selected for the study. They were classified into two groups, Control Group (200 students) and Experimental Group (200 students).

3.1 Instrumentation

The experimental group expressed a willingness to undertake the drills and they were willing to have GSR level monitored through a GSR sensor meter. Consent for getting testing done with a GSR meter was on the personal data form. The institutes’ ethics committees gave permission for conducting this experimental study. The respondents signed a consent form for participating in drills and for GSR measurement. Physiological parameter GSR was monitored through a digital electronic GSR Sensor Meter for experimental recordings manufactured by Psychometric Research, London (U.K.). The meter was used for non-destructive testing on the participants [19].

3.2 Intervention

The experimental subjects (#200) were exposed to listening to drills of yogic breathing, religious hymns and flute music for 300 seconds and the GSR meter responses were noted after the 300 seconds. Experimental group was exposed to all above 3 drills separately not simultaneously.

The control group was not exposed to any drill and they were simply made to sit on chair.

The following steps were followed for both the control group and the experimental group:

The subject sat on a comfortable, relaxing chair. The hand portion was made fully moisture free.

The meter electrodes were attached to forefinger and first finger of the hand. The initial reading of the GSR (micro siemen) was recorded using GSR meter at t = zero second. The manual instructions for use of the meter were followed [19].

The time frame for carrying out each drill of entire experiment was 40 days. The whole process was repeated for each of the subjects.

Musical religious hymns and yogic breathing were used separately by engineering students to find out whether or not they were effective in reducing stress. Both of these strategies were effective in reducing stress [12, 13]. The research was extended to try another strategy, i.e. listening to flute music. The current study compares the effect of these three drills to identify the most effective strategy for relieving stress among young technical graduate students. In this study, listening to flute music and yogic breathing are used as stimuli and their effects are observed on physiological parameters through use of the GSR Sensor Meter.

The study used the following three drills for experimental group to identify the most effective strategy for reducing stress.

undergoing yogic deep breathing

listening to religious hymns

listening to flute

Control Group (No Drill)

Subject sat on chair

GSR attached to hand fingers

GSR Reading noted at t = o second

No drill given

GSR Reading noted at t = 300 seconds

Experimental Group (undergoing yogic deep breathing)

Subject sat on chair

GSR attached to hand fingers

Eyes Closed

GSR Reading noted at t = o second

Inhale into abdomen with ease

Exhale with ease

Keep repeating inhaling and exhaling in above way up to 300 seconds

GSR Reading noted at t = 300 seconds

Experimental Group (listening to religious hymns)

Subject sat on chair

GSR attached to hand fingers

Eyes Closed

GSR Reading noted at t = o second

Subject is made to listen to religious hymn up to 300 seconds

GSR Reading noted at t = 300 seconds

Experimental Group (listening to flute music)

Subject sat on chair

GSR attached to hand fingers

Eyes Closed

GSR Reading noted at t = o second

Subject is made to listen to flute music up to 300 seconds

GSR Reading noted at t = 300 seconds

The study hypotheses are:

There is a significant difference in the GSR value for the control group not exposed to any drill (before i.e. t = zero second and after i.e. t = 300 seconds).

There is a significant difference in the GSR value of the experimental group being exposed to yogic breathing (before i.e. t = zero second and after i.e. t = 300 seconds).

There is a significant difference in the GSR value of the experimental group being exposed to religious hymns (before i.e. t = zero second and after i.e. t = 300 seconds).

There is a significant difference in the GSR value of the experimental group being exposed to flute music (before i.e. t = zero second and after i.e. t = 300 seconds).

4 Results

The present study uses t-test for analysis of the difference in GSR readings amongst the engineering students on the basis of type of drill and time lapsed. The 200 participants of the control group were not exposed to any drill. As shown on Table 1, the mean value of control group not exposed to music for pre: t = 0 second is 63.58 and post: t = 300 seconds is 68.69. The variance is 199.41 and 208.99 respectively. As the t-Stat (11.97) is greater than value of t Critical two-tail (2.60) and p-value is significant (p < 0.01), hence H₁ is accepted. Thus, there is a significant difference in the GSR for students not exposed to any drill for pre-test and post-test. The mean value increased from 63.58 (t = zero second) to 68.69 (t = 300 second). This signifies that GSR increased for the control group.

Table 1
Statistical analysis (Pre & Post) GSR (micro siemen) Values

t-Test: Paired two sample for means Control group (no treatment)

t = 0 second (Pre) t = 300 seconds (Post)

Mean 63.58 68.69

Variance 199.41 208.99

Observations 199 199

t Stat –11.97

df 198

p value ≤0.001 ≤0.001

t Critical two-tail 2.60 2.60

t-Test: Paired two sample for means	Control group (no treatment)
Mean	63.58	68.69
Variance	199.41	208.99
Observations	199	199
t Stat	–11.97
df	198
p value	≤0.001	≤0.001
t Critical two-tail	2.60	2.60

The Experimental Group (Table 2) showed mean value of skin conductivity in students undergoing deep breathing as 71.14 at t = 0 sec (pre), 63.95 at t = 300 secs (post) and a variance of 237.29 and 286.90 respectively. The mean value of pre (71.14) > mean value of post (63.95) at t Stat = 17.18 > t Critical two-tail (2.60). The p value (two-tail) < 0.01, was significant. So, Hypothesis H_2a was accepted. Thus, there was a significant difference in the skin conductivity between pre and post participants undergoing deep breathing. However, mean value decreased from 71.14 (t = 0 sec) to 63.95 (t = 300 secs) which showed that skin conductivity decreased for the experimental group.

Table 2

Statistical analysis (Pre & Post) GSR (micro siemen) Values

t-Test: Paired two sample for means	Experimental group (Undergoing deep yogic breathing)
	t = 0 sec (Pre)	t = 300 sec (Post)
Mean	71.14	63.95
Variance	237.29	286.90
Observations	199	199
t Stat	17.18
df	198
p value	≤0.001
t Critical two-tail	2.60

As reflected through Table 3 the mean value of GSR is 69.39 at t = 0 second. The subjects were made to listen to hymns and the mean value of GSR is 62.61 at t = 300 seconds. The variance recorded is 250.27 and 299.54 respectively for pre and post. The value of t-Statistics is 19.35, which is greater than t Critical two-tail (2.60), and p value ≤0.01.

Table 3

Statistical analysis (Pre & Post) GSR (micro siemen) Values

t-Test: paired two sample for means	Experimental group (Listening to Hymns)
	t = 0 second (Pre)	t = 300 seconds (Post)
Mean	69.39	62.61
Variance	250.27	299.54
t Stat	19.35	–
df	198
p value	≤0.001	–
t Critical two-tail	2.60	–

Thus, hypothesis H2b: there is a significant difference in mean GSR value of experimental group at t = zero second and t = 300 seconds has also been accepted. Thus, it can be inferred that there is a significant reduction in the mean GSR after listening to hymns.

The experimental group was exposed to flute music. As shown in Table 4, the mean value of GSR was 70.23 before listening to flute music and the mean value of GSR after exposure decreased to 62.49. The mean value pre exposure (70.23) is greater than mean value post exposure (62.49). Value of t-Stat (18.47) is greater than value of t-Critical two-tail (2.60) and is significant with p < .01. Thus, H_2c is accepted. There is a significant difference in the GSR (pre-test and post-test) for students listening to flute music. The decrease in mean value signifies a positive influence of music on the experimental group. The study compared the results of three drills, viz. undertaking yogic breathing and listening to musical religious hymns and listening to flute. The results are shown in Table 5. The results clearly indicate that although all three drills were effective in reducing stress, exposure to flute music emerged as the most effective stimulus. Flute music emerges as the most effective strategy for reducing stress in comparison to yogic breathing and religious musical hymns. The results highlight the effectiveness of flute music as a form of slow soothing music on stress reduction.

Table 4

Statistical analysis (Pre & Post) GSR (micro siemen) Values

t-Test: Paired two sample for means	Experimental group (listening to flute music)
	t = 0 second (Pre)	t = 300 seconds (Post)
Mean	70.23	62.49
Variance	209.43	276.59
t Stat	18.47	–
df	198
p value	≤0.001	–
t Critical two-tail	2.60	–

Table 5

Mean GSR Value (Pre and Post) for Control and Experimental Groups for all stimuli at 0.001 significance level

S No.	Type of stimulus	t = 0 second (Pre value)	t = 300 seconds (Post value)	Difference in Mean GSR values
1.	No Drill: Control Group (n = 200)	63.58	68.69	+5.11
2.	Undergoing Yogic Breathing (n = 200)	71.14	63.95	–7.19
3.	Listening to Musical Hymns (n = 200)	69.39	62.61	–6.78
4.	Listening to Flute Music (n = 200)	70.23	62.49	–7.74

5 Discussion

High stress can lead to depression. High stress can reflect poor grades and dismal placement records. Stress should be monitored. There is a need to focus on stress management strategies. High stress levels of engineering students have attracted the attention of researchers. Rao (2015) focused on the increased number of suicides at IIT-Bombay due to high stress level of the students [20]. Joshi et al. (2011) proposed the development of a stress management laboratory in Indian educational institutions to be equipped with modern electronic instruments. After specialized training, faculty and staff can assist in reducing stress of students by monitoring physiological parameters leading to mental stressors [21].

The authors believe that our present educational system has too much focus on academic performance and fails to nurture personality development of the students. The relationships among life stress, social support, and academic stressors have been investigated earlier [22]. Listening to music, especially slow, quiet classical music can have a relaxing effect on the mind and body [23]. The present study demonstrated flute music can help reduce stress of engineering students.

The GSR meter measures the responses due to the different frequencies stimulated by the flute. In an earlier study [24], it was shown that blood pressure and the stress level of engineering students can be controlled by deep breathing techniques. The present study extends this protocol to listening to flute music as a strategy for relieving stress. Our study lends further support to using flute music for reducing stress. It has been proved that the GSR meter records the autonomic nervous system [25]. Eminent researchers like Salam (2013), Wiech & Tracey (2009), Obrist (1963), Villarejo et al. (2012), Thomas et al. (2013) have supported the use of a GSR meter for measuring stress [5 , 26–30]. The researchers have investigated physical and psychological issues of work and job stress in various types of industries [31]. The present research reinforces the application of GSR technology as a bio feedback sensor [32].

Experimental analyses to monitor and manage stress among engineering students using other techniques like musical hymns and breathing were tried successfully [12, 13]. This study compares the effect of three drills on stress, viz. undertaking yogic breathing, listening to musical hymns, and listening to flute. The comparison helps to determine the most effective strategy for coping with stress. Table 5 shows the related data. The difference in the mean values of the experimental group is highest for listening to flute (–7.74). This was followed by undertaking yogic breathing (–7.19) and listening to musical hymns (–6.78). The difference in the mean values of the control group was +5.11. That shows that for the control group stress. increased. The control group not exposed to any drill reported higher values for GSR. The graphical representation shown in Fig. 1 highlights that the most effective stimulus for managing stress of engineering students was listening to flute music. This was followed by yogic breathing and listening to musical religious hymns. All three strategies, undertaking yogic breathing, listening to religious musical hymns, and listening to flute, helped reduce stress levels among engineering students but listening to flute music emerged as the most effective strategy.

Fig. 1

Pre and post mean GSR comparison for control group and experimental group for various drills. X axis: 1: Control group; 2: Experimental group yogic breathing; 3: Experimental group musical religious hymns; 4: Experimental group flute.

6 Conclusion

It can be affirmed that flute music, yogic breathing, and musical religious hymns were effective in managing stress among engineering students. This study results suggest problems related to stress amongst youth can be effectively reduced through the use of these strategies. These strategies for managing stress can be extremely effective in reducing stress of engineering students. Listening to flute music is the most effective in comparison to the other strategies.

7 Limitations

Similar to other studies based on primary data, the current study also has some limitations. The study is based on assumption that data provided by subjects reflected their actual perception. For future studies, the sample size can be increased. This is an initial endeavour but the results are encouraging. For deeper understanding of the issues, the study could utilize various other stress management techniques including listening to a variety of musical instruments and measuring not only GSR but other physiological parameters like pulse rate and blood pressure. Managing and controlling stress is an immediate need for further study because high stress levels among engineering students can hinder not only productivity but also make it difficult to succeed and thrive in the globally competitive workforce. After leaving the institutes, engineering students may find it extremely challenging to cope with the numerous pressures of work. It has become imperative to manage stress through simple and cost-effective strategies.

8 Recommendations

Based on these findings, it is proposed that educational institutes introduce these simple and cost-effective strategies to manage stress. Flute music emerged as the most effective strategy for reducing stress in comparison to yogic breathing and religious musical hymns.

In addition, the biofeedback practise of monitoring stress levels with a GSR meter could be adopted by institutes for learning. These, strategies can help to mitigate the prevailing high levels of stress experienced by engineering students. Not only can stress levels be reduced but these strategies can lead to enhanced performance, helping students lead a happy life.

9 Future studies

The study used a recommended GSR technology and advocated its usage to examine the levels of stress in engineering students. The study can be extended to use various other stress management techniques and measuring GSR to understand for deeper analysis. The other physiological parameters like respiration rate, pulse rate and blood pressure can also be tested in addition to GSR. It is time to think intensely about managing and controlling stress as it is deep-rooted malaise and tackling it, is the immediate concern.

Conflict of interest

None to report.

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