Auditory stimulation to reduce procedure pain in neonates: A scoping review

Abstract

Introduction

The application of auditory system stimulation, either through music or vocals, to reduce pain in neonates as a vulnerable group is very beneficial. However, some researchers have indicated that this auditory stimulation does not yield positive results in reducing pain in neonates. The standard for applying this auditory stimulation intervention to reduce pain in neonates during painful procedures is still unclear.

Aim

To identify and map the literature on auditory stimulation using music or vocals as a non-pharmacological analgesia method for neonates undergoing painful procedures during their hospital care.

Method

A scoping review. We followed the JBI methodology for scoping reviews. Keywords were directed at five key concepts: auditory, pain, music, neonates, and stimulation. Information retrieval was focused on MEDLINE (PubMed), CINAHL (EBSCO), Embase, and Scopus (Elsevier) from the period of 2015 to 2024.

Results

Twenty-eight studies were identified as meeting the criteria for this review. Four were quasi-experiment studies, and the remaining were randomized control trials. There were six elements of auditory stimulation to reduce pain, which were the type of auditory stimulation, content, time, delivery methods, sound intensity, and combination with other methods. We highlighted the promising role of music as an adjunctive pain management strategy for neonates undergoing painful procedures.

Conclusion

The incorporation of additional sensory modalities to reinforce auditory input should be considered; we found that multisensory stimulation yielded more favorable analgesic outcomes.

What is already known about the topic.

• •Sensory stimulation can effectively reduce pain in neonates, whether applied as a unisensory or multisensory intervention.
• •Auditory stimulation for neonatal pain relief may include instrumental music, music with lyrics, or the mother’s voice.
• •Clear distinctions exist between the terms music therapy and music medicine, although they are often misused in literature.

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What this paper adds.

• •Auditory stimulation through music should follow standardized protocols that include core components grounded in evidence-based practice.
• •Combining auditory stimulation with other sensory modalities may enhance pain relief, highlighting the need for further studies using rigorous research designs.
• •We emphasized accurate use of the terms music therapy and music medicine, addressing common terminological inconsistencies in published research.

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1. Introduction

The pain experience among hospitalized neonates remains high, with approximately 11.6 % experiencing painful conditions and 84.1 % being exposed to at least one potentially-painful procedure in Sweden (Graham et al., 2025). Various analgesia methods have been developed, both pharmacologically and non-pharmacologically (Shen et al., 2022). Infant sensory stimulation, whether single or a combination of several senses, is an approach widely used as non-pharmacological analgesia (Mangat et al., 2018). This is likely related to the principle of the pain modulation pathway, which is sensitive to sensory stimulation. Three mechanisms by which the pain response may be modulated have been identified: gate control, the descending modulatory system, and neuromodulators (Liu & Kelliher, 2022).

Various studies have been conducted to develop analgesic methods for neonates using this auditory sensory system stimulation approach (Jain et al., 2019; Papatzikis et al., 2024). Auditory stimulation can take the form of music or human vocal sounds, either live or recorded, which are defined as music therapy or music medicine (Haslbeck et al., 2023). The role of music is believed to reduce pain intensity and physiological functions in neonates (Shah, Kadage and Sinn, 2017; Maitre and Arnon, 2020). However, some researchers have shown that music has no effect in reducing pain in neonates (Ramli et al., 2021a). This difference of opinion may be caused by varying intervention standards. The implementation of auditory stimulation shows a wide range of methods, and, technically, only a few are implemented formally and standardized. Auditory stimulation, in its various forms, is recognized as a recommended non-pharmacological intervention to reduce pain intensity in neonates; however, existing evidence predominantly focuses on studies evaluating music-based stimulation.

Intervention standards are needed in the application of music or vocal sounds with their variations to achieve positive effects in reducing pain in neonates. To establish an accurate intervention standard, it is necessary to map the concepts and identify the components involved in the application of music or vocal interventions. We aimed to map the available evidence on auditory stimulation to reduce pain in neonates undergoing painful procedures. The objective of this scoping review was to explore and describe what was reported about auditory stimulation in reducing pain in neonates who underwent painful procedures in the hospital.

2. Methods

For this scoping review, we followed the JBI methodology (Aromataris, 2024).

2.1. Inclusion criteria

Concept

We emphasized the concept of auditory stimulation used for analgesic purposes, including both music and vocal sounds.

Context

We considered studies that cover settings in hospitals, specifically in neonatal care units at various levels. Neonatal care levels range from Level I (basic care for healthy newborns) to Level III (complex care in neonatal intensive care unit). Participants of the studies were neonates of all gestational ages who experienced invasive procedures.

2.2. Types of sources and search strategy

The types of studies were quantitative, including experimental designs and observational designs, and English-language sources published between 2015 – 2024. Based on the recommendation by JBI (Aromataris, 2024), a search strategy consists of three stages. Stage 1 consisted of a limited initial search conducted in two online databases (Medline/PubMed and Scopus) using keywords aligned with the inclusion criteria (neonates, pain, auditory stimulation, and music), including analysis of article titles and abstracts to identify relevant topics. A second stage comprises a search that uses all identified keywords, and index terms should then be undertaken across all included databases. As the third stage, the reference list of identified reports and articles is searched for additional sources.

2.3. Study selection

Following the search, studies were independently selected according to the inclusion criteria based on their title and abstract by WR and SH. In the case of discordance, SYRF was consulted. Studies that might meet the inclusion criteria were retrieved in full, and their details were imported into the EndNote Web library database. See Fig. 1 for the PRISMA 2020 flow diagram.

Fig. 1.

PRISMA 2020 flow chart.

2.4. Data extraction

Data charting was conducted using a structured data extraction form developed by the authors. The form was used to systematically extract information on population, concept, context, study methods, and key finding relevant to the review objectives.

3. Results

3.1. Characteristics of included sources

All the sources included in this review (N = 28) were interventional; of these, four articles were quasi-experiments, and the remaining were randomized controlled trials.

3.2. Procedures performed

The painful procedures performed on 2628 full-term and preterm infants included: venipuncture, tracheal aspiration, nasal aspiration, removal of intravenous lines, removal of adhesives, peripherally inserted central catheter, continuous positive airway pressure, aspiration after intubation, heel stick, injection, endotracheal suction, circumcision, blood sampling, and retinopathy of prematurity examination

3.3. Key findings identified from the data

Based on the data mapping process, six elements of auditory stimulation were identified as non-pharmacological analgesia for neonates undergoing painful procedures. These are described in detail below:

3.3.1. Type of auditory stimulation

Auditory stimulation in this review refers to the optimization of hearing, focused as an analgesic function for neonates undergoing painful procedures. Generally, the types of auditory interventions used were music (both instrumental music and music with lyrics), as well as recordings of the mother's voice (in the form of singing, rhymes, poetry, or storytelling)

3.3.2. Content or substance or rhythm of auditory type

The content depended on the type of auditory stimulation used. Music with lyrics: The lyrics in the music used as analgesia included those from popular song titles in the location where the research was conducted, which were generally lullaby songs. See Table 1 for song titles.

Table 1.

Data extraction (Listed chronologically).

No	Study, country	Purpose	Sample	Auditory type	Time	Outcome measures	Title of music or vocal	Combination intervention	Painful intervention	Methods	Results
1	Azarmnejad, et al. (2015), Iran	To determine the effect of familiar auditory stimuli on the arterial blood sampling (ABS) induced pain in term neonates.	30 newborns	The recorded mothers' voices.	10 min before, during and 10 min after the intervention (immediately after completion of the sound).	NIPS	The recorded mothers' voices played for the neonate by two small loudspeakers (200 V Sony) on both sides of the head at a distance of 20 cm from the neonate’s ear, and it was set at 50–60 dB	None	Blood sampling	Randomly controlled group	The mother's voice reduces ABS induced pain.
2	Zhu, et al. (2015), China	To test the effectiveness of BF, MT, and combined BFMT on pain relief during heel lance.	288 healthy term neonates	Music	5 min before heel lance and maintained during blood sampling	NIPS	Three classical music pieces – Souvenirs D'enfance, A Comme Amour, and Ballade Pour Adeline played by Richard Clayderman	Breastfeeding + music	Heel lance.	Prospective, randomised, controlled	Music therapy cannot enhance the effectiveness of breast feeding on pain relief and there is no need for the additional input of classical music in clinics where breast 3feeding is u4sed to relieve procedural pain.
3	Alemdar & Özdemir, (2017), Turkey	To identify the effect of covering the eyes and playing the intrauterine ambient sounds on premature infants' pain and physiological parameters during venipuncture.	94 preterm infants	Heart beat sound in form of The Sleeping Baby CD, through speaker system and MP3	15 min before, during, and 15 min after the venipuncture.	NIPS	The Sleeping Baby CD: specific relaxing music similar to real heartbeat sounds, converted technologically to intrauterine sounds familiar to the infant. Volume intensity set to 45 dB	None	Venipuncture	Randomized controlled trial	Significant difference between the NIPS scores of the intervention and control groups
4	Azarmnejad, et al. (2017), Iran	This study sought to examine the effects of the familiar auditory stimulus on the physiologic responses to pain of venipuncture among neonates	60 full‐term neonates	Recorded maternal voice	10 min before to 10 min after the venipuncture procedure	Physiologic parameters: HR, RR, systolic blood pressures, diastolic blood pressures, and Sa O2	Recorded maternal voice Each speaker was placed 20 cm away from neonate’s ears and outside the incubator. The intensity of maternal sound was set at 50 to 60 dB	None	Venipuncture	Quasi-experimental	Maternal voice is effective in reducing some physiologic parameters
5	Chirico, et al. (2017), Italy	To evaluated effects of recorded maternal voices in limiting pain in preterm infants undergoing heel lance procedures	40 pre term infants in NICU	Recording of mother voice	10 min, twice a day for three consecutive days	PIPP	Maternal voice (lullaby, nursery rhymes)	None	Heel lance procedures	Prospective, randomised, case control study	Using recorded maternal voices to limit pain in preterm infants undergoing heel lance procedures appeared safe and effective.
6	Shah, et al. (2017), Australia	To compare the effectiveness of music, oral sucrose, and combination therapy for pain relief in neonates undergoing a heel prick procedure.	35 term neonates have been crossed over to all 3 interventions	Recorded instrumental music	Starting 20 min before the heel prick, continuing for 7 min after the procedure.	PIPP-R	Recorded instrumental music: “Deep Sleep” track from “Bedtime Mozart: Classical Lullabies for Babies”	Music + Sucrose	Heel prick	Randomized, controlled, blinded crossover clinical trial	The combination of music therapy with sucrose provided better pain relief
7	Qiu, et al. (2017) China	To examine the impact and mechanism of CMT intervention on the pain response in premature infants.	62 preterm neonates	Music from compact disc player was placed 15 – 20 cm above the infant’s head	Music was played 5 min before the experimental procedure until 30 min after the procedure.	PIPP	Lullaby and nursery rhymes (simple song) with lower pitch and slower tempo, with intensity 55 – 65 dB	Touch	Tracheal aspiration, nasal aspiration, removal of intravenous lines, and removal of adhesives	Randomized controlled trial	Combined Music and Touch might decrease the pain response
8	Alemdar and Tüfekçi (2018) Turkey	To evaluate the effects of providing prerecorded maternal heart sounds on the level of pain and comfort that are experienced by preterm infants during aspiration.	62 preterm infants	Recording of mother’s heart sound	15 min before, during and continued for 15 min after the aspiration	PIPP, PICS and physiological parameters	A hand Doppler and a MP3 players were used to record the heart sounds of the infants’ mothers that it then played through a speaker that was set to 45 db	None	Aspiration after the intubation process.	Randomized controlled trial.	Intervention with maternal heart sounds effectively reduced pain
9	Rossi, et al.(2018), Italy	To assess the effects of three different musical interventions compared to no music on the physiological responses (including pain perception, heart rate, and oxygen saturation) of healthy newborns undergoing painful medical procedures.	80 full-term newborns aged 1 – 3 days	Music tracks and recoded heartbeat	40 min	NIPS	The three interventions included Mozart's Sonata for two pianos, Beethoven's Moonlight Sonata and heartbeat sound recordings, (70 bpm).	None	Guthrie test and intramuscular antibiotic injections	Prospective, randomized controlled trial	Music interventions can reduce stress and pain
10	Tang, et al. (2018), China	To investigate the application of a MI during PICC placement procedures in premature infants.	60 premature infants	Music from MP4-player with small mobile speaker	10 min before PICC puncture and continued until 10 min after opera- tion completion	PIPP Cortisol levels	Lullabies and nursery rhymes, and more than 10 pieces of children's music with slower tempo was selected from “Chinese children music library” and the volume was adjusted to 50–60 dB.	None	PICC	Randomized, data-analysts-blinded, controlled trial	Music intervention significantly reduced stress hormone levels, physiological parameters and behavioral response of pain.
11	Jain, et al. (2019), India	To evaluate vocal and music in preventing pain in newborn babies	50 full term newborns	Music instrument and music with lyric (vocal music)	Not clearly stated Music was started after collecting baseline values and was continued during the procedure	NIPS	Piano music (instrumental music) and Rockabye baby music (vocal music) was played at 60dB	None	BCG Vaccination	Interventional study	Vocal music can reduce the pain
12	Tekgündüz, et al. (2019), Turkey	To investigate whether oral glucose and listening to lullabies could reduce pain during the removal and reinsertion of the tracheal tube and oronasopharyngeal suctioning to whom nasal continuous positive airway pressure was applied	106 premature infants	Music	During intervention until the intervention completed	NIPS, and PIPP	Listened to lullabies through a portable speaker located around 30 cm away from their heads in the incubator with 50 – 60 dB sound level	Oral sucrose/glucose + music	Removal and reinsertion of the tracheal tube and oronasopharyngeal suctioning	A double-blind, randomized controlled trial.	The findings suggest that pain could be reduced significantly after the suggested intervention (glucose and lullaby music), although further studies are required to identify the benefits of lullabies or glucose in infants during other painful procedures.
13	Barandouzi, et al. (2020), Iran	To compare the analgesic effects of sucrose, music, and their combination on venipuncture’s pain in preterm neonates.	120 preterm	Music instrumental was played via headphone	10 min	PIPP	Brahms’s lullaby music with 40−50 dB was played for 10 min via a headphone.	Sucrose + music	Venipuncture	Double-blinded clinical trial	Music could relieve pain 30 s after the venipuncture completion but not during the venipuncture.
14	Kahraman, et al. (2020), Turkey	To investigate the effects of three auditory interventions; white noise, recorded mother’s voice, and MiniMuffs, applied during a heel lance on pain and comfort in premature infants in the neonatal intensive care units.	64 premature infants with gestational ages of 31–36 weeks.	White noise Recorded mother’s voice	5 min before and during the heel lance.	NIPS and the COMFORTneoscale. .	White noise: intra uterine sounds from Dr. Harvery Karp’s ‘‘The Happiest Baby”. Recorded mothers’ voice (whatever mothers want to say to their infants) was placed on the tip of the foot at about 30 cm from the ear of the neonate and sound level was set to 50 dB. MiniMuffs: placed on their ears five minutes before the procedure to reduce the environmental noise.	None	Heel lance	Parallel, randomized controlled	The interventions reduce the pain and increase the comfort of the premature infants.
15	Ravikumar, et al. (2020), India	To determine whether vestibular stimulation offered by Indian hammock and music interventions are useful in reducing the occurrence of infantile colic in term infants	465 term neonates weighing more than 1500 g	Music recording	4 h a day with one stretch of at least 1 h	N/A Prevalence of infantile colic episode as defined by ROME IV criteria.	Lullabies and songs (of the south Indian culture) in the vernacular language were sung and recorded for duration of 30 min used CD player with speaker or cell phone, tablet or laptop with 30 cm away from baby. This recorded music based on guidelines by Schwartz	None	Infantile colic	Open-labelled, prospective randomized controlled trial	Vestibular stimulation by Indian hammock and music intervention individually reduced the occurrence of infantile colic.
16	Barcellos, et al. (2021)	To evaluate the effects of music therapy on the PTNBs on non-invasive ventilation	30 preterm newborns	Instrumental music from earphone connected to DVD	20 min	HR, RF, AT, SaO2, and NIPS	Instrumental music developed by a musician for using it specifically with hospitalized newborns. The sound was not to exceed 60 db	None	Non-invasive ventilation on the CPAP mode	Quasi-experimental study	Music therapy interferes positively with the PTNBs
17	Chen, et al. (2021), China	To evaluate the effect of maternal voice on pain caused by venipuncture (including peripheral venipuncture and femoral venipuncture) in neonates hospitalized in the NICU.	116 neonates	Recording of maternal voice	A recording of 10 min duration. Maternal voice was played for 2 min before the procedure and until the neonate's heart rate and oxygen saturation returned to baseline (all phases completed)	NIAPAS	Singing or reading nursery rhymes	None	Venipuncture	Experimental, randomized controlled study.	Recorded maternal voice can improve pain
18	Lakhkar & Patil, (2021), India	To observe the effects of music therapy on pain relief in neonates and compare the effects of instrumental music and vocal music during IV cannulation in the NICU	66 term neonates	Music recorded	3–6 min; music was played 3 min before the procedure until a minimum of 3 min after the procedure.	NIPS	The vocal music used recorded lullaby in the Marathi language. The instrumental music was a recorded sitar tune. The recorder was kept 1 m away from the neonate, and, using a sound meter, the volume was kept below 55 dB	None	Intra Vena cannulation	Prospective, interventional study	The mean post-procedure pain score in the vocal music group was higher than that in the instrumental music group
19	Ramli, et al. (2021), Indonesia	To evaluate the effects of music intervention on physiological parameters and pain perception in healthy newborns undergoing a painful medical procedure	51 newborns	Music instrument	10 min (total duration): 5 min and continued for 5 min after the injection	NIPS	The instrumental lullaby "Nina Bobo".	None	Injection for hepatitis B vaccination	Double-blind, randomized control trial study	Music intervention did not significantly affect pain perception or oxygen saturation in newborns during hepatitis B vaccination.
20	Sarhangi, et al. (2021), Iran	To examine the effect of the mother’s heartbeat sound on physiological parameters and pain intensity after blood sampling in neonates in the intensive care unit.	60 full-term neonates	The mother’s heartbeat sound	10 min before up to 10 min after taking arterial blood samples	NIPS	The mother’s heartbeat sound for each neonate was recorded by the Cool Edit2000 software using the Summit Doppler Sonicade Series L350 (Summit Doppler Company®, USA)	None	The arterial blood sampling procedure	Randomized controlled clinical trial	Listening to the mother’s heartbeat sound did not influence on mean arterial pressure in the intervention group. However, it had significant medium to large effects on oxygen saturation and respiratory rate.
21	Taplak & Bayat, (2021), Turkey	To determine the effect of the breastmilk smell, white noise and facilitated tucking during ES on pain and physiological findings	80 preterm infants	White noise	started 5 min before the procedure and continued up to 5 min after the procedure	PIPP-R	The white noise composed of the mother's womb environment and real heartbeat sound and relaxing music. The infant listened to the piece through two mini loud speakers of an MP3 player that was placed to the right and left of the infant's feet	None	Endotracheal suctioning	Randomized, controlled experimental trial	White noise and facilitated tucking were effective in relieving pain
22	Melo et al. (2022), Brazil	To evaluate the effect of music combined to swaddling on the behavioural (facial action) and physiological (heart rate) response of pain full-term newborns, before and during venous puncture for blood collection.	52 infants	Music instrumental from headset	10 min and 15 min	NFCS	Instrumental of lullabies from the baby music collection (Bone Nuit) with 40 dB intensity using headset Group 1: music 10 min + swaddling Group 2: music 15 min + swaddling	Swaddling + music	Venipuncture	Randomized, triple blind, factorial clinical trial.	The intervention showed a greater absence of facial pain actions.
23	Sharara-Chami, et al. (2022), Lebanon	To assess the potential adjunct analgesic effect of music during neonatal circumcision	103 healthy newborn males	Music medicine	Started 5 min before the procedure until the end of the procedure.	NIPS	Auditory stimulation was provided by playing the “Baby Go to Sleep” playlist which contains nursery rhymes, all songs were played via iPad at 50 dB	None	The circumcision	Double blind randomized controlled trial comparing EMLA + Sucrose + RB + Music (Intervention) to EMLA + Sucrose + RB (Control)	The addition of music to the effective analgesia established for neonatal circumcision did not improve NIPS scores
24	Yu et al., (2022), Taiwan	This study aimed to examine the effectiveness of maternal voice in alleviating premature infants' pain during the heel sticks and facilitating mother–infant bonding during hospitalization	64 pre- mature infant–mother dyads	Recording of mother’s voice (reading a children book)	13 min in total (3 min before and lasting until the heel stick procedure completion)	NIPS	Voice recordings of the mother reading a children's book were created The intensity was between 50 and 60 dB.	None	Heel stick	Randomized controlled trial	The maternal voice intervention slowed the heart rate and alleviated the pain response
25	Apaydin Cirik, et al. (2023), Turkey	To measure the outcome of five various non-pharmacologic pain relief groups; maternal voice, white noise, holding, maternal voice + holding, and white noise + holding.	178 newborns (postnatal age between 1 and 5 days)	The maternal voice The white noise group: “The Happiest Baby,” was used in the white noise group.	5 min before, during, and 5 min after the heel stick.	NIPS, and PIPP	Recording of maternal voice of telling their babies whatever they wanted. The speaker was placed approximately 30 cm away from the infant's ear, and it set to 50–60 dB on average	Maternal voice + holding White noise + holding	The heel stick sampling	Open label, randomized controlled trial.	There was no significant difference between the groups in terms of oxygen saturation score. The white noise + holding applied to newborns during heel stick sampling were effective in pain reduction.
26	Belpınar & Yayan, (2023), Turkey	To evaluate the effects of Yakson touch and mother’s voice on pain and comfort levels of preterm infants during nasal CPAP application.	124 premature infants	Recording of Mother voice (voice of singing) from smartphones (The Mother’s Voice Play Device)	20 min (5 min before, during, and 15 min after the application)	NIPS, and PICS	Lullabies sung by mothers. The mother’s voice recording was placed in the baby’s incubator, about 10–15 cm from the infant’s head, the phone noise to below 50 dB.	Yakson touch + mother’s voice	CPAP	Randomized experimental study	Yakson touch and mother’s voice+Yakson touch methods are effective in neonatal pain and comfort
27	Patel, et al. (2023), India	To determine the effectiveness of music therapy on pain reduction during painful procedures among preterm neonates.	60 preterm neonates	pre-recorded music	5 min received music therapy during and after painful procedure	NPASS	Lullaby with instrumental music (pre-recorded music)	None	painful procedures	Quasi-experimental study	Music therapy was effective in the reduction of pain
28	Çuhacı, et al. (2024), Turkey	To determine the effect of music applied during the ROP examination on pain, comfort, and physiological parameters in preterm infants.	28 preterm infants.	Music instrumental	3 min before the ROP examination procedure, played throughout the procedure, and terminated 3 min after the procedure.	PIPP-R, and PICS.	Music of Acem Aşiran Maqam by the TÜMATA was played at volume 45–60 dB.	None	The retinopathy of prematurity examination	Prospective randomized controlled double-blind experimental study	The intervention decreased the pain scores, had a positive effect on the PICS scores after the procedure, but did not affect the physiological parameters positively.

Abbreviation: AT-Axillary Temperature, BCG-Bacillus Calmette-Guérin, BF- Breast Feeding, BFMT- Breast Feeding and Music Therapy, CD-Compact Disc, CMT-Combined Music and Touch, CPAP- Continuous Positive Airway Pressure, dB-Decibel, DVD-Digital Versatile Disc, HR- Heart Rate, MT-Music Therapy, NFCS- Neonatal Facial Coding System, NIAPS-Neonatal Infant Acute Pain Assessment Scale, NICU-Neonatal Intensive Care Unit, NIPS- Neonatal Infant Pain Scale, NPAS- The Neonatal Pain Agitation and Sedation Scale, PICC-Peripherally Inserted Central Catheter, PICS- Premature Infant Comfort Scale, PIPP- Premature Infant Pain Profile, PIPP-R- Revised-Premature Infant Pain Profile, PTNBs- Pre Term Newborns, RF-Respiratory Frequency, ROP-Retinopathy of Prematurity, RR-Respiratory Rate, SaO₂ - Saturation oxygen

Instrumental music (without lyrics): For music using instruments only, the rhythm was based on classical music. See Table 1 for specifics.

For recordings of the mother’s voice, the content includes singing songs, the mother reading a book, reciting poetry/rhymes, or telling any stories she wanted to convey to her baby

3.3.3. Time

The timing of providing music or the mother's vocalization varied in both duration and sequence. The duration of the intervention ranged from 3 min to 40 min. The intervention was administered before, during, and after the procedure.

3.3.4. Delivery methods

The music and vocalizations given to the baby were delivered using various assistive devices. See Table 1 for the specific type. For music played through speakers, the distance between the speaker and the baby was set between 20 to 30 cm from the head or feet.

3.3.5. Sound intensity

The sound intensity of the music or the mother's recorded voice ranged from 40 to 65 dB.

3.3.6. Combination with the other method of analgesia

Some studies combined music with other analgesic methods, such as sucrose, touch, swaddling, breastfeeding, and holding.

In general, most researchers showed the effect of music in reducing pain, with only one group of researchers reporting a non-significant reduction in pain levels (Ramli et al., 2021b). The pain-reducing effect of music was observed in various conditions or characteristics. Music medicine was generally administered using a variety of devices. Some were applied directly, such as headphones, while others were utilized indirectly—placed at a certain distance from the infant—such as cellphones or external speakers from MP3 and MP4 players. These indirectly-used devices were typically positioned approximately 20–30 cm from the infant’s body. The anatomical reference point for measuring this distance varied, with some studies referring to the ears, head, or feet.

4. Discussion

Based on the type of music provided for health purposes, all these types are part of music medicine. Music medicine is a non-pharmacological intervention in which the patient listens to pre-recorded music pre-selected by medical staff or selected by the patient from available programs (Dileo, 1999). However, in the articles in this study, the primary term used was music therapy, even though music therapy refers to a therapeutic process, including a music therapist and a relationship developed through the music experience and that therapeutic process (Dileo, 1999). Therefore, in future research, the use of this term needs to be aligned with the way the type of music is presented.

To date, there is no universally accepted standard regarding the ideal distance between the infant and the device serving as the music source. Nonetheless, concerns regarding electromagnetic radiation emitted from these devices warrant careful consideration. Generally recommended safe distance between electronic devices, such as headphones or cellphones, and the human body is at least 20 cm (The Maryland Children’s Environmental Health and Protection Advisory Council, 2022).

Electromagnetic radiation arises from electronic devices due to the emission of electromagnetic fields, particularly in wireless or Bluetooth-enabled systems. These fields are a byproduct of the device’s operating mechanisms. Given the heightened sensitivity of infants to environmental exposures, the use of electronic devices near their bodies may carry potential radiation-related risks (Moon, 2020). Consequently, the direct application of such devices on infants should be approached with caution, and efforts should be made to minimize potential exposure.

Music inherently contributes to pain reduction in neonates through auditory stimulation; however, the involvement of additional sensory modalities appears to enhance the analgesic effects of music. Previous researchers have shown that multisensory stimulation is more effective in alleviating pain compared to stimulation of a single sensory pathway (Bellieni et al., 2002; Fitri et al., 2020). In relation to the ongoing discourse between music therapy and music medicine, it is important to note that music medicine typically involves passive auditory stimulation, whereas music therapy is generally delivered through active engagement and personal interaction between the therapist and the infant. Therefore, the analgesic effects of music may be more optimally achieved through music therapy. Nevertheless, if music medicine is to be employed, its effectiveness is likely to be enhanced when combined with other non-pharmacological analgesic methods that engage additional sensory modalities beyond auditory input—such as tactile, gustatory, olfactory, or visual stimulation. The method of delivering music or sound also requires careful consideration.

The use of safe media is essential to ensure neonatal safety. While the primary goal of using headphones, earphones, or speakers is to reduce pain, these devices should not introduce other risks related to electromagnetic radiation. Further research is needed to address this issue, as no studies have specifically examined the impact of using such electronic devices on neonatal safety. In addition to safety considerations, future researchers should further investigate the function of music by employing auditory stimulation intervention protocols that are precise and well-defined in all components—such as the type of music or voice used, rhythm, harmonic structure, duration and intensity of exposure, patient characteristics, and environmental conditions. Moreover, clinical trials utilizing standardized and methodologically rigorous research designs are essential to establish evidence-based practices in this field.

4.1. Limitations

The study quality and risk of bias were not appraised. Considerable heterogeneity existed in auditory interventions, pain assessment tools, neonatal characteristics, and clinical settings which limited comparability. The restriction to selected databases and English-language publications may have resulted in the exclusion of relevant studies.

5. Conclusion

Auditory stimulation requires further empirical investigation within rigorously controlled settings. The incorporation of additional sensory modalities to reinforce auditory input should be considered, as evidence suggests that multisensory stimulation yields more favorable analgesic outcomes. Furthermore, the conceptual distinctions between music therapy and music medicine must be clearly understood and accurately applied in both clinical implementation and research design. Future research can be conducted to test the clinical protocol developed based on this review, which can then serve as a foundation for developing policies related to pain management in neonates.

CRediT authorship contribution statement

Siti Yuyun Rahayu Fitri: Supervision, Funding acquisition, Formal analysis, Conceptualization. Windy Rakhmawati: Writing – review & editing, Investigation, Formal analysis. Sri Hendrawati: Writing – review & editing, Investigation.

Declaration of competing interest

The authors declare that they have no known competing financial interest or personal relationships that could have appeared to influence the work reported in this manuscript.