Musical agency reduces perceived exertion during strenuous physical performance

Sensorimotor synchronization to music reduces pain

Pain-reducing effects of music listening are well-established, but the effects are small and their clinical relevance questionable. Recent theoretical advances, however, have proposed that synchronizing to music, such as clapping, tapping or dancing, has evolutionarily important social effects that are associated with activation of the endogenous opioid system (which supports both analgesia and social bonding). Thus, active sensorimotor synchronization to music could have stronger analgesic effects than simply listening to music. In this study, we show that sensorimotor synchronization to music significantly amplifies the pain-reducing effects of music listening. Using pressure algometry to the fingernails, pain stimuli were delivered to n = 59 healthy adults either during music listening or silence, while either performing an active tapping task or a passive control task. Compared to silence without tapping, music with tapping (but not simply listening to music) reduced pain with a large, clinically significant, effect size (d = 0.93). Simply tapping without music did not elicit such an effect. Our analyses indicate that both attentional and emotional mechanisms drive the pain-reducing effects of sensorimotor synchronization to music, and that tapping to music in addition to merely listening to music may enhance pain-reducing effects in both clinical contexts and everyday life. The study was registered as a clinical trial at ClinicalTrials.gov (registration number NCT05267795), and the trial was first posted on 04/03/2022.

Auditory Personalization of EMDR Treatment to Relieve Trauma Effects: A Feasibility Study [EMDR+]

According to the WHO (World Health Organization), Eye Movement Desensitization and Reprocessing (EMDR) is an elective therapy to treat people with post-traumatic stress disorders (PTSD). In line with the personalization of therapeutic strategies, through this pilot study, we assessed in people suffering from the effects of trauma the feasibility, safety, acceptance, and efficacy of EMDR enriched with sound stimulation (by administering neutral sounds synchronized with the guided bilateral alternating stimulation of the gaze) and musical reward (musical listening based on the patients' predisposition and personal tastes). Feasibility, quantified by the number of patients who completed the treatment, was excellent as this was the case in 12 out of the 12 enrolled people with psychological trauma. Safety and acceptance, assessed by self-compiled questionnaires, were excellent, with an absence of side effects and high satisfaction. Efficacy, quantified by the number of EMDR treatment sessions required to reach the optimal scores on the Subjective Units of Disturbance (SUD) and Validity of Cognition (VOC) scales typical of EMDR protocols, revealed an average duration of 8.5 (SD 1.2) sessions, which is well below the 12 sessions considered a standard EMDR treatment duration. EMDR+ appears to be a relevant personalization of EMDR, particularly in music-sensitive people, consolidating the therapeutic alliance through a multisensory communicative bond for trauma treatment.

Effects of active musical engagement during physical exercise on anxiety, pain and motivation in patients with chronic pain

The experience of anxiety is central to the development of chronic pain. Music listening has been previously shown to exert analgesic effects. Here we tested if an active engagement in music making is more beneficial than music listening in terms of anxiety and pain levels during physical activity that is often avoided in patients with chronic pain. We applied a music feedback paradigm that combines music making and sports exercise, and which has been previously shown to enhance mood. We explored this method as an intervention to potentially reduce anxiety in a group of patients with chronic pain (N = 24, 20 female and 4 men; age range 34–64, M = 51.67, SD = 6.84) and with various anxiety levels. All participants performed two conditions: one condition, Jymmin, where exercise equipment was modified with music feedback so that it could be played like musical instruments by groups of three. Second, a conventional workout condition where groups of three performed exercise on the same devices but where they listened to the same type of music passively. Participants' levels of anxiety, mood, pain and self-efficacy were assessed with standardized psychological questionnaires before the experiment and after each condition. Results demonstrate that exercise with musical feedback reduced anxiety values in patients with chronic pain significantly as compared to conventional workout with passive music listening. There were no significant overall changes in pain, but patients with greater anxiety levels compared to those with moderate anxiety levels were observed to potentially benefit more from the music feedback intervention in terms of alleviation of pain. Furthermore, it was observed that patients during Jymmin more strongly perceived motivation through others. The observed diminishing effects of Jymmin on anxiety have a high clinical relevance, and in a longer term the therapeutic application could help to break the Anxiety Loop of Pain, reducing chronic pain. The intervention method, however, also has immediate benefits to chronic pain rehabilitation, increasing the motivation to work out, and facilitating social bonding.

Enhanced Short-Term Memory Function in Older Adults with Dementia Following Music-Feedback Physical Training: A Pilot Study

Prior research demonstrates that music making, physical exercise, and social activity have unique, positive effects on cognition and mood. One intervention, “Jymmin^®”, was developed incorporating these approaches and found effective for decreased pain perception and increased endurance, self-efficacy, mood, and muscle efficiency. Previously, Jymmin was not piloted with older adults with dementia. The current study is a randomized pilot study of the Jymmin^® with an older adult population in a long-term care facility (n = 38), evaluated across dementia levels (mild, moderate, or severe). Results found significant improvements in scores on a confrontation naming task across all conditions (p = 0.047) and a significant interaction effect for short-term memory scores (p = 0.046), suggesting higher scores at Time 2 for the experimental group and at Time 3 for the control group. There were no significant changes in mood ratings. Findings are discussed in the context of neural activity and musical agency.

Musical feedback system Jymmin® leads to enhanced physical endurance in the elderly—A feasibility study

Background and objectives

Active music-making in combination with physical exercise has evoked several positive effects in users of different age groups. These include enhanced mood, muscular effectivity, pain threshold, and decreased perceived exertion. The present study tested the applicability of this musical feedback system, called Jymmin^®, in combination with strength-endurance exercises in a population of healthy older adults.

Research design and methods

Sixteen healthy, physically inactive older adults (5 males, 11 females) at the mean age of 70 years performed physical exercise in two conditions: A conventional work-out while listening passively music and a Jymmin^® work-out, where musical sounds were created with one's work-out movements. According to the hypothesis that strength-endurance is increased during musical feedback exercise, parameters relating to strength-endurance were assessed, including exercise duration, number of repetitions, perceived exertion (RPE), and participants' mental state (Multidimensional Mood State Questionnaire; MDMQ).

Results

Results show that participants exercised significantly longer while doing Jymmin^® (Mdn = 248.75 s) as compared to the conventional work-out (Mdn = 182.73 s), (Z = 3.408, p = 0.001). The RPE did not differ between conventional work-out and the Jymmin^® condition, even though participants worked out significantly longer during the Jymmin^® condition (Mdn = 14.50; Z = −0.905; p = 0.366). The results of the MDMQ showed no significant differences between both conditions (Z = −1.037; p = 0.300).

Discussion and implications

Results show that participants could work out longer while showing the same perceived exertion, relating to increased physical endurance. Music feedback work-out encouraged a greater degree of isometric contractions (muscle actively held at fixed length) and, therefore, less repetitions in this condition. In addition to the previously described effect on muscle effectivity, this non-stereotypic contraction pattern during music feedback training may have enhanced endurance in participants supporting them to better proportion energetic reserves during training (pacing).

Clinical trial registration

Identifier: DRKS00023645.

Am I (Deep) Blue? Music-Making AI and Emotional Awareness

Artificial Intelligence has shown paradigmatic success in defeating world champions in strategy games. However, the same programming tactics are not a reasonable approach to creative and ostensibly emotional artistic endeavors such as music composition. Here we review key examples of current creative music generating AIs, noting both their progress and limitations. We propose that these limitations are rooted in current AIs lack of thoroughly embodied, interoceptive processes associated with the emotional component of music perception and production. We examine some current music-generating machines that appear to be minimally addressing this issue by appealing to something akin to interoceptive processes. To conclude, we argue that a successful music-making AI requires both the generative capacities at which current AIs are constantly progressing, and thoroughly embodied, interoceptive processes which more closely resemble the processes underlying human emotions.

Components of Active Music Interventions in Therapeutic Settings-Present and Future Applications

Musical interventions in therapy have become increasingly relevant for rehabilitation in many clinics. What was long known for physiotherapy training-that the agency of the participant is crucial and moving is much more efficient for rehabilitation success than being moved-has over recent years also been shown to be true for music therapy. Accumulating evidence suggests that active musical interventions are especially efficient at helping rehabilitation success. Here, we review various approaches to active music therapy. Furthermore, we present several components that allow for manipulating musical expressiveness and physical engagement during active musical interventions, applying a technology-based music feedback paradigm. This paper will allow for a transfer of insights to other domains of music-based therapeutic interventions.

The Effects of Preferred Music and Its Timing on Performance, Pacing, and Psychophysiological Responses During the 6‐min Test

The aim of this study was to investigate the effects of listening to preferred music during a warm up or exercise, on performance during a 6-min all-out exercise test (6-MT) in young adult males. Twenty-five healthy males volunteered to participate in this study. Following a within subject design, participants performed three test conditions (MDT: music during the test; MDW: music during the warm-up; WM: without music) in random order. Outcomes included mean running speed over the 6-min test (MRS6), total distance covered (TDC), heart rate responses (HR_peak, HR_mean), blood lactate (3-min after the test), and the rating of perceived exertion (RPE); additionally, feeling scale scores were recorded. Listening to preferred music during running resulted in significant TDC (Δ↑10%, p=0.006, ES=0.80) and MRS6 (Δ↑14%, p=0.012, ES=1.02) improvement during the 6-MT, improvement was also noted for the warm-up with music condition (TDC:Δ↑8%, p=0.028, ES=0.63; MRS6:Δ↑8%, p=0.032, ES=0.61). A similar reverse “J-shaped” pacing profile was detected during the three conditions. Blood lactate was lower in the MDT condition by 8% (p=0.01, ES=1.10), but not the MDW condition, compared to MW. In addition, no statistically significant differences were found between the test sessions for the HR, RPE, and feeling scale scores. In conclusion, listening to music during exercise testing would be more beneficial for optimal TDC and MRS6 performances compared to MDW and WM.

The Feasibility and Acceptability of Neurologic Music Therapy in Subacute Neurorehabilitation and Effects on Patient Mood

Music interventions support functional outcomes, improve mood, and reduce symptoms of depression in neurorehabilitation. Neurologic music therapy (NMT) has been reported as feasible and helpful in stroke rehabilitation but is not commonly part of multidisciplinary services in acute or subacute settings. This study assessed the feasibility and acceptability of delivering NMT one-day-per-week in a subacute neurorehabilitation centre over 15 months. Data were collected on the number of referrals, who referred, sessions offered, attended, and declined, and reasons why. Staff, patients, and their relatives completed questionnaires rating the interventions. Patients completed the Visual Analog Mood Scales (VAMS) pre and post a single session. Forty-nine patients received 318 NMT sessions (83% of sessions offered). NMT was rated as helpful or very helpful as part of the multidisciplinary team (n = 36). The highest ratings were for concentration, arm and hand rehabilitation, and motivation and mood. VAMS scores (n = 24) showed a reduction in ‘confused’ (−8.6, p = 0.035, effect size 0.49) and an increase in ‘happy’ (6.5, p = 0.021, effect size = 0.12) post NMT. The data suggest that a one-day-per-week NMT post in subacute neurorehabilitation was feasible, acceptable, and helpful, supporting patient engagement in rehabilitation exercises, mood, and motivation.

Collectively playable wearable music: Practice-situated approaches to participatory relational inquiry

We present two practice-situated participatory investigations using networked wearable sensors to develop movement-responsive collectively playable musical instruments: a series of four collocated workshops for expert dancers and a distance learning course in which students use wearable technology to enhance embodied learning and feelings of connectedness telematically. We reflect on our exploration of techniques for structuring ensemble improvisations augmented with bespoke digital musical instruments using aggregate statistical measures, such as variance of participants' physical orientation as an index of group intention. Participatory design exchanges top-down design methodologies with bottom-up approaches consulting actors' interests. We follow this approach by evolving our instruments through abductive experiments and trial-and-error tinkering, without strong theories, methods, or models, using elementary signal processing techniques that are meaningfully understood and modified by participants. Our experiences suggest useful scaffolding techniques for educational transdisciplinary research-creation communities seeking to explore relational ensemble dynamics in telematic and/or physically collocated settings using accessible wearable technologies. Through creative inquiry and participation, technical objects can become bearers of sense and meaning rather than instating mystifying or alienating relations for the participants.

Musicality in human vocal communication: an evolutionary perspective

Studies show that specific vocal modulations, akin to those of infant-directed speech (IDS) and perhaps music, play a role in communicating intentions and mental states during human social interaction. Based on this, we propose a model for the evolution of musicality-the capacity to process musical information-in relation to human vocal communication. We suggest that a complex social environment, with strong social bonds, promoted the appearance of musicality-related abilities. These social bonds were not limited to those between offspring and mothers or other carers, although these may have been especially influential in view of altriciality of human infants. The model can be further tested in other species by comparing levels of sociality and complexity of vocal communication. By integrating several theories, our model presents a radically different view of musicality, not limited to specifically musical scenarios, but one in which this capacity originally evolved to aid parent-infant communication and bonding, and even today plays a role not only in music but also in IDS, as well as in some adult-directed speech contexts. This article is part of the theme issue 'Voice modulation: from origin and mechanism to social impact (Part II)'.

The Power of Musification: Sensor-Based Music Feedback Improves Arm Swing in Parkinson's Disease

Background

Reduction of arm swing during gait is an early and common symptom in Parkinson's disease (PD). By using the technology of a mobile phone, acceleration of arm swing can be converted into a closed‐loop musical feedback (musification) to improve gait.

Objectives

To assess arm swing in healthy subjects and the effects of musification on arm swing amplitude and other gait parameters in patients with PD.

Methods

Gait kinematics were analyzed in 30 patients during a 320 m walk in 3 different conditions comprising (1) normal walking; (2) focused swinging of the more affected arm; and (3) with musification of arm swing provided by the iPhone application CuraSwing. The acceleration of arm swing was converted into musical feedback. Arm swing range of motion and further gait kinematics were analyzed. In addition, arm swing in patients was compared to 32 healthy subjects walking at normal, slow, and fast speeds.

Results

Musification led to a large and bilateral increase of arm swing range of motion in patients. The increase was greater on the more affected side of the patient (+529.5% compared to baseline). In addition, symmetry of arm swing, sternum rotation, and stride length increased. With musical feedback patients with PD reached arm swing movements within or above the range of healthy subjects.

Conclusions

Musification has an immediate effect on arm swing and other gait kinematics in PD. The results suggest that closed‐loop musical feedback is an effective technique to improve walking in patients with PD.

Application of step and beat alignment approaches and its effect on gait in progressive multiple sclerosis with severe cerebellar ataxia: A proof of concept case study

BACKGROUND

In a case report of a progressive multiple sclerosis with cerebellar impairments, we reported that synchronisation of steps to beats was possible only at -12% of usual walking cadence during 1 minute of walking.

OBJECTIVES AND METHODS

Here, we investigate the effect of synchronisation using two different alignment approaches on the patient's gait pattern over 2 minutes of walking, compared to walking in silence.

RESULTS AND CONCLUSION

This proof of concept showed that the adaptive approach was successful resulting in an improved gait pattern compared to the other conditions, providing preliminary evidence to support a full-scale intervention study.

‘Unusual ingredients’: Developing a cross-domain model for multisensory artistic practice linking food and music

This article explores linkages between sensory experiences of food and music in light of recent research from gastrophysics, 4E cognition (i.e. embodied, embedded, extended and enactive) and ecological perception theory. Drawing on these research disciplines, this article outlines a model for multisensory artistic practice, and a taxonomy of cross-domain creative strategies, based on the identification of sensory affordances between the domains of food and music. Food objects are shown to ‘afford’ cross-domain interrelationships with sound stimuli based on our capacity to sense their material characteristics, and to make sense of them through prior experience and contextual association. We propose that multisensory artistic works can themselves afford extended forms of sensory awareness by synthesizing and mediating stimuli across the selected domains, in order to form novel, or unexpected sensory linkages. These ideas are explored with reference to an ongoing artistic research project entitled ‘Unusual ingredients’, creating new music to complement and enhance the characteristics of selected food.

Musical Interaction Reveals Music as Embodied Language

Life and social sciences often focus on the social nature of music (and language alike). In biology, for example, the three main evolutionary hypotheses about music (i.e., sexual selection, parent-infant bond, and group cohesion) stress its intrinsically social character (Honing et al., 2015). Neurobiology thereby has investigated the neuronal and hormonal underpinnings of musicality for more than two decades (Chanda and Levitin, 2013; Salimpoor et al., 2015; Mehr et al., 2019). In line with these approaches, the present paper aims to suggest that the proper way to capture the social interactive nature of music (and, before it, musicality), is to conceive of it as an embodied language, rooted in culturally adapted brain structures (Clarke et al., 2015; D'Ausilio et al., 2015). This proposal heeds Ian Cross' call for an investigation of music as an "interactive communicative process" rather than "a manifestation of patterns in sound" (Cross, 2014), with an emphasis on its embodied and predictive (coding) aspects (Clark, 2016; Leman, 2016; Koelsch et al., 2019). In the present paper our goal is: (i) to propose a framework of music as embodied language based on a review of the major concepts that define joint musical action, with a particular emphasis on embodied music cognition and predictive processing, along with some relevant neural underpinnings; (ii) to summarize three experiments conducted in our laboratories (and recently published), which provide evidence for, and can be interpreted according to, the new conceptual framework. In doing so, we draw on both cognitive musicology and neuroscience to outline a comprehensive framework of musical interaction, exploring several aspects of making music in dyads, from a very basic proto-musical action, like tapping, to more sophisticated contexts, like playing a jazz standard and singing a hocket melody. Our framework combines embodied and predictive features, revolving around the concept of joint agency (Pacherie, 2012; Keller et al., 2016; Bolt and Loehr, 2017). If social interaction is the "default mode" by which human brains communicate with their environment (Hari et al., 2015), music and musicality conceived of as an embodied language may arguably provide a route toward its navigation.

How groove in music affects gait

Rhythmic auditory stimulation (RAS) is a gait intervention in which gait-disordered patients synchronise footsteps to music or metronome cues. Musical 'groove', the tendency of music to induce movement, has previously been shown to be associated with faster gait, however, why groove affects gait remains unclear. One mechanism by which groove may affect gait is that of beat salience: music that is higher in groove has more salient musical beats, and higher beat salience might reduce the cognitive demands of perceiving the beat and synchronizing footsteps to it. If groove's effects on gait are driven primarily by the impact of beat salience on cognitive demands, then groove's effects might only be present in contexts in which it is relevant to reduce cognitive demands. Such contexts could include task parameters that increase cognitive demands (such as the requirement to synchronise to the beat), or individual differences that may make synchronisation more cognitively demanding. Here, we examined whether high beat salience can account for the effects of high-groove music on gait. First, we increased the beat salience of low-groove music to be similar to that of high-groove music by embedding metronome beats in low and high-groove music. We examined whether low-groove music with high beat salience elicited similar effects on gait as high-groove music. Second, we examined the effect of removing the requirement to synchronise footsteps to the beat (i.e., allowing participants to walk freely with the music), which is thought to remove the cognitive demand of synchronizing movements to the beat. We tested two populations thought to be sensitive to the cognitive demands of synchronisation, weak beat-perceivers and older adults. We found that increasing the beat salience of low-groove music increased stride velocity, but strides were still slower than with high-groove music. Similarly, removing the requirement to synchronise elicited faster, less variable gait, and reduced bias for stability, but high-groove music still elicited faster strides than low-groove music. These findings suggest that beat salience contributes to groove's effect on gait, but it does not fully account for it. Despite reducing task difficulty by equalizing beat salience and removing the requirement to synchronise, high-groove music still elicited faster, less variable gait. Therefore, other properties of groove also appear to play a role in groove's effect on gait.

Increasing Divergent Thinking Capabilities With Music-Feedback Exercise

Divergent thinking is an essential aspect of creativity and has been shown to be affected both by music and physical exercise. While it has been shown that making music and physical exercise can be beneficial for Divergent Thinking in isolation, it is unclear whether the effects can be combined. The present experiment investigated the relation of physical exertion and being in control of music on Divergent Thinking and the possibility of an interaction effect. Seventy-seven predominantly young, German participants were tested with measurements of Divergent Thinking collected after either (1) physical exercise with music listening, (2) making music with a knob setup without physical effort (music control only), or (3) making physical exercise with musical feedback (Jymmin™). Results showed greater increases in Divergent Thinking scores following music-feedback exercise compared to conditions of physical exercise with music listening and music control only. The data thus demonstrate that making music part of a physical exercise routine more strongly leads to the benefit of increased creative capacities, which we argue will be beneficial for athletes to prepare for certain types of competition/performance and as part of regeneration training.

Instructed versus spontaneous entrainment of running cadence to music tempo

Matching exercise behavior to musical beats has been shown to favorably affect repetitive endurance tasks. In this study, our aim was to explore the role of spontaneous versus instructed entrainment, focusing on self‐paced exercise of healthy, recreational runners. For three 4‐min running tasks, 33 recreational participants were either running in silence or with music; when running with music, either no instructions were given to entrain to the music, or participants were instructed to match their running cadence with the tempo of the music. The results indicated that less entrainment occurred when no instruction to match the exercise with the musical tempo was provided. In addition, similar to the condition without music, lower speeds and shorter step lengths were observed when runners were instructed to match their running behavior to the musical tempo when compared with the condition without such instruction. Our findings demonstrate the impact of instruction on running performance and stress the importance of intention to entrain running behavior to musical beats.

Origins of music in credible signaling

Music comprises a diverse category of cognitive phenomena that likely represent both the effects of psychological adaptations that are specific to music (e.g., rhythmic entrainment) and the effects of adaptations for non-musical functions (e.g., auditory scene analysis). How did music evolve? Here, we show that prevailing views on the evolution of music - that music is a byproduct of other evolved faculties, evolved for social bonding, or evolved to signal mate quality - are incomplete or wrong. We argue instead that music evolved as a credible signal in at least two contexts: coalitional interactions and infant care. Specifically, we propose that (1) the production and reception of coordinated, entrained rhythmic displays is a co-evolved system for credibly signaling coalition strength, size, and coordination ability; and (2) the production and reception of infant-directed song is a co-evolved system for credibly signaling parental attention to secondarily altricial infants. These proposals, supported by interdisciplinary evidence, suggest that basic features of music, such as melody and rhythm, result from adaptations in the proper domain of human music. The adaptations provide a foundation for the cultural evolution of music in its actual domain, yielding the diversity of musical forms and musical behaviors found worldwide.

Timing Markers of Interaction Quality During Semi-Hocket Singing

Music is believed to work as a bio-social tool enabling groups of people to establish joint action and group bonding experiences. However, little is known about the quality of the group members' interaction needed to bring about these effects. To investigate the role of interaction quality, and its effect on joint action and bonding experience, we asked dyads (two singers) to perform music in medieval "hocket" style, in order to engage their co-regulatory activity. The music contained three relative inter-onset-interval (IOI) classes: quarter note, dotted quarter note and eight note, marking time intervals between successive onsets (generated by both singers). We hypothesized that singers co-regulated their activity by minimizing prediction errors in view of stable IOI-classes. Prediction errors were measured using a dynamic Bayesian inference approach that allows us to identify three different types of error called fluctuation (micro-timing errors measured in milliseconds), narration (omission errors or misattribution of an IOI to a wrong IOI class), and collapse errors (macro-timing errors that cause the breakdown of a performance). These three types of errors were correlated with the singers' estimated quality of the performance and the experienced sense of joint agency. We let the singers perform either while moving or standing still, under the hypothesis that the moving condition would have reduced timing errors and increased We-agency as opposed to Shared-agency (the former portraying a condition in which the performers blend into one another, the latter portraying a joint, but distinct, control of the performance). The results show that estimated quality correlates with fluctuation and narration errors, while agency correlates (to a lesser degree) with narration errors. Somewhat unexpectedly, there was a minor effect of movement, and it was beneficial only for good performers. Joint agency resulted in a "shared," rather than a "we," sense of joint agency. The methodology and findings open up promising avenues for future research on social embodied music interaction.

Listening to Preferred Music Improved Running Performance without Changing the Pacing Pattern during a 6 Minute Run Test with Young Male Adults

Several studies have investigated the effects of music on both submaximal and maximal exercise performance at a constant work-rate. However, there is a lack of research that has examined the effects of music on the pacing strategy during self-paced exercise. The aim of this study was to examine the effects of preferred music on performance and pacing during a 6 min run test (6-MSPRT) in young male adults. Twenty healthy male participants volunteered for this study. They performed two randomly assigned trials (with or without music) of a 6-MSPRT three days apart. Mean running speed, the adopted pacing strategy, total distance covered (TDC), peak and mean heart rate (HRpeak, HRmean), blood lactate (3 min after the test), and rate of perceived exertion (RPE) were measured. Listening to preferred music during the 6-MSPRT resulted in significant TDC improvement (Δ10%; p = 0.016; effect size (ES) = 0.80). A significantly faster mean running speed was observed when listening to music compared with no music. The improvement of TDC in the present study is explained by a significant overall increase in speed (main effect for conditions) during the music trial. Music failed to modify pacing patterns as suggested by the similar reversed “J-shaped” profile during the two conditions. Blood-lactate concentrations were significantly reduced by 9% (p = 0.006, ES = 1.09) after the 6-MSPRT with music compared to those in the control condition. No statistically significant differences were found between the test conditions for HRpeak, HRmean, and RPE. Therefore, listening to preferred music can have positive effects on exercise performance during the 6-MSPRT, such as greater TDC, faster running speeds, and reduced blood lactate levels but has no effect on the pacing strategy.

The Influence of Auditory Cues on Bodily and Movement Perception

The sounds that result from our movement and that mark the outcome of our actions typically convey useful information concerning the state of our body and its movement, as well as providing pertinent information about the stimuli with which we are interacting. Here we review the rapidly growing literature investigating the influence of non-veridical auditory cues (i.e., inaccurate in terms of their context, timing, and/or spectral distribution) on multisensory body and action perception, and on motor behavior. Inaccurate auditory cues provide a unique opportunity to study cross-modal processes: the ability to detect the impact of each sense when they provide a slightly different message is greater. Additionally, given that similar cross-modal processes likely occur regardless of the accuracy or inaccuracy of sensory input, studying incongruent interactions are likely to also help us predict interactions between congruent inputs. The available research convincingly demonstrates that perceptions of the body, of movement, and of surface contact features (e.g., roughness) are influenced by the addition of non-veridical auditory cues. Moreover, auditory cues impact both motor behavior and emotional valence, the latter showing that sounds that are highly incongruent with the performed movement induce feelings of unpleasantness (perhaps associated with lower processing fluency). Such findings are relevant to the design of auditory cues associated with product interaction, and the use of auditory cues in sport performance and therapeutic situations given the impact on motor behavior.

The sonic instructor: A music-based biofeedback system for improving weightlifting technique

In this study, we assumed that correct functional movements for weightlifting can be learned with the help of a music-based biofeedback system. We compared musical feedback with verbal feedback from experienced trainers using two independent groups. The focus was on one specific movement called deadlift. Physical parameters under considerations were the spine (i.e. loss of midline stability resulting in flexion) and the forward displacement of the barbell during the repetitions relative to the mid-foot. We recruited 31 recreational weight lifters (21-42 years of age). Results revealed that both feedback types are effective in improving the movements for deadlift. No significant differences were found across the two feedback types, neither in terms of movement, nor in terms of clarity and motivation. The results suggest that the proposed feedback system is a valid tool for technology-aided training and self-training practices.

Walking to Music and Metronome at Various Tempi in Persons With Multiple Sclerosis: A Basis for Rehabilitation

Background. Mobility dysfunctions are prevalent in persons with multiple sclerosis (PwMS), thus novel rehabilitation mechanisms are needed toward functional training. The effect of auditory cueing is well-known in Parkinson's disease, yet the application of different types of auditory stimuli at different tempi has not been investigated yet. Objectives. Investigating if PwMS, compared with healthy controls (HC), can synchronize their gait to music and metronomes at different tempi during walking and the effects of the stimuli on perceived fatigue and gait. Additionally, exploring if cognitive impairment would be a factor on the results. Methods. The experimental session consisted of 2 blocks, music and metronomes. Per block, participants walked 3 minutes per tempi, with instructions to synchronize their steps to the beat. The tempi were 0%, +2%, +4% +6%, +8%, +10% of preferred walking cadence (PWC). Results. A total of 28 PwMS and 29 HC participated. On average, participants were able to synchronize at all tempi to music and metronome. Higher synchronization was obtained for metronomes compared with music. The highest synchronization for music was found between +2% and +8% of PWC yet pwMS perceived less physical and cognitive fatigue walking to music compared with metronomes. Cognitive impaired PwMS (n = 9) were not able to synchronize at tempi higher than +6%. Conclusion. Auditory-motor coupling and synchronization was feasible in HC and PwMS with motor and cognitive impairments. PwMS walked at higher tempi than their preferred walking cadence, and lower fatigue perception with music. Coupling walking to music could be a promising functional walking training strategy.

Optimizing beat synchronized running to music

The use of music and specifically tempo-matched music has been shown to affect running performance. But can we maximize the synchronization of movements to music and does maximum synchronization influence kinematics and motivation? In this study, we explore the effect of different types of music-to-movement alignment strategies on phase coherence, cadence and motivation. These strategies were compared to a control condition where the music tempo was deliberately not aligned to the running cadence. Results show that without relative phase alignment, a negative mean asynchrony (NMA) of footfall timings with respect to the beats is obtained. This means that footfalls occurred slightly before the beat and that beats were anticipated. Convergence towards this NMA or preferred relative phase angle was facilitated when the first music beat of a new song started close to the step, which means that entrainment occurred. The results also show that using tempo and phase alignment, the relative phase can be manipulated or forced in a certain angle with a high degree of accuracy. Ensuring negative angles larger than NMA (step before beat) results in increased motivation and decreasing cadence. Running in NMA or preferred relative phase angles results in a null effect on cadence. Ensuring a positive phase angle with respect to NMA results in higher motivation and higher cadence. None of the manipulations resulted in change in perceived exhaustion or a change in velocity. Results also indicate that gender plays an important role when using forced phase algorithms: effects were more pronounced for the female population than for the male population. The implementation of the proposed alignment strategies and control of beat timing while running opens possibilities optimizing the individual running cadence and motivation.

In dubio pro silentio - Even Loud Music Does Not Facilitate Strenuous Ergometer Exercise

Background: Music listening is wide-spread in amateur sports. Ergometer exercise is one such activity which is often performed with loud music.

Aim and Hypotheses: We investigated the effects of electronic music at different intensity levels on ergometer performance (physical performance, force on the pedal, pedaling frequency), perceived fatigue and heart rate in healthy adults. We assumed that higher sound intensity levels are associated with greater ergometer performance and less perceived effort, particularly for untrained individuals.

Methods: Groups of high trained and low trained healthy males (N = 40; age = 25.25 years; SD = 3.89 years) were tested individually on an ergometer while electronic dance music was played at 0, 65, 75, and 85 dB. Participants assessed their music experience during the experiment.

Results: Majorities of participants rated the music as not too loud (65%), motivating (77.50%), appropriate for this sports exercise (90%), and having the right tempo (67.50%). Participants noticed changes in the acoustical environment with increasing intensity levels, but no further effects on any of the physical or other subjective measures were found for neither of the groups. Therefore, the main hypothesis must be rejected.

Discussion: These findings suggest that high loudness levels do not positively influence ergometer performance. The high acceptance of loud music and perceived appropriateness could be based on erroneous beliefs or stereotypes. Reasons for the widespread use of loud music in fitness sports needs further investigation. Reducing loudness during fitness exercise may not compromise physical performance or perceived effort.

Musical Agency during Physical Exercise Decreases Pain

Objectives: When physical exercise is systematically coupled to music production, exercisers experience improvements in mood, reductions in perceived effort, and enhanced muscular efficiency. The physiology underlying these positive effects remains unknown. Here we approached the investigation of how such musical agency may stimulate the release of endogenous opioids indirectly with a pain threshold paradigm. Design: In a cross-over design we tested the opioid-hypothesis with an indirect measure, comparing the pain tolerance of 22 participants following exercise with or without musical agency. Method: Physical exercise was coupled to music by integrating weight-training machines with sensors that control music-synthesis in real time. Pain tolerance was measured as withdrawal time in a cold pressor test. Results: On average, participants tolerated cold pain for ~5 s longer following exercise sessions with musical agency. Musical agency explained 25% of the variance in cold pressor test withdrawal times after factoring out individual differences in general pain sensitivity. Conclusions: This result demonstrates a substantial pain reducing effect of musical agency in combination with physical exercise, probably due to stimulation of endogenous opioid mechanisms. This has implications for exercise endurance, both in sports and a multitude of rehabilitative therapies in which physical exercise is effective but painful.

The Sound of Success: Investigating Cognitive and Behavioral Effects of Motivational Music in Sports

Listening to music before, during, or after sports is a common phenomenon, yet its functions and effects on performance, cognition, and behavior remain to be investigated. In this study we present a novel approach to the role of music in sports and exercise that focuses on the notion of musical self-enhancement (Elvers, 2016). We derived the following hypotheses from this framework: listening to motivational music will (i) enhance self-evaluative cognition, (ii) improve performance in a ball game, and (iii) evoke greater risk-taking behavior. To evaluate the hypotheses, we conducted a between-groups experiment (N = 150) testing the effectiveness of both an experimenter playlist and a participant-selected playlist in comparison to a no-music control condition. All participants performed a ball-throwing task developed by Decharms and Davé (1965), consisting of two parts: First, participants threw the ball from fixed distances into a funnel basket. During this task, performance was measured. In the second part, the participants themselves chose distances from the basket, which allowed their risk-taking behavior to be assessed. The results indicate that listening to motivational music led to greater risk taking but did not improve ball-throwing performance. This effect was more pronounced in male participants and among those who listened to their own playlists. Furthermore, self-selected music enhanced state self-esteem in participants who were performing well but not in those who were performing poorly. We also discuss further implications for the notion of musical self-enhancement.

3Mo: A Model for Music-Based Biofeedback

In the domain of sports and motor rehabilitation, it is of major importance to regulate and control physiological processes and physical motion in most optimal ways. For that purpose, real-time auditory feedback of physiological and physical information based on sound signals, often termed “sonification,” has been proven particularly useful. However, the use of music in biofeedback systems has been much less explored. In the current article, we assert that the use of music, and musical principles, can have a major added value, on top of mere sound signals, to the benefit of psychological and physical optimization of sports and motor rehabilitation tasks. In this article, we present the 3Mo model to describe three main functions of music that contribute to these benefits. These functions relate the power of music to Motivate, and to Monitor and Modify physiological and physical processes. The model brings together concepts and theories related to human sensorimotor interaction with music, and specifies the underlying psychological and physiological principles. This 3Mo model is intended to provide a conceptual framework that guides future research on musical biofeedback systems in the domain of sports and motor rehabilitation.

The Band Effect-Physically Strenuous Music Making Increases Esthetic Appreciation of Music

The esthetic appreciation of music is strongly influenced by cultural background and personal taste. One would expect that this would complicate the utilizability of musical feedback in paradigms, such that music would only be perceived as a reward if it complies to personal esthetic appreciation. Here we report data where we assessed esthetic appreciation of music after 1. a physically strenuous music improvisation and 2. after passive music listening (where participants esthetically assessed similar music). Data are reported from two experiments with different patient groups: 1. Drug abuse patients, and 2. Chronic pain patients. Participants in both experiments performed Jymmin, a music feedback method where exercise equipment is modified in such a way that it can be played like musical instruments by modulating musical parameters in a composition software. This combines physical exertion with musical performance in a fashion that has previously been shown to have a number of positive psychological effects such as enhanced mood and reduced perceived exertion. In both experiments esthetic appreciation of musical presentations during Jymmin and a control condition without musical agency were compared. Data show that both patient groups perceived the musical outcome of their own performance as more esthetically pleasing than similar music they listened to passively. This suggests that the act of making music (when combined with physical exertion) is associated with a positivity bias about the perceived esthetical quality of the musical outcome. The outcome of personal musical agency thus tends to be perceived as rewarding even if it does not comply with personal esthetic appreciation. This suggests that musical feedback interventions may not always have to be highly individualized because individual taste may not always be crucial. The results also suggest that the method applied here may be efficient at encouraging music listeners to actively explore new musical styles that they might otherwise be reluctant to listen to (e.g., avant-garde music). The results also hint toward a deeper understanding of why musicians, who exert themselves physically during musical performances to generate music and regardless of the type of music they are playing, typically find the physically demanding experience esthetically satisfying.

"It Don't Mean a Thing if It Ain't Got that Swing"- an Alternative Concept for Understanding the Evolution of Dance and Music in Human Beings

The functions of dance and music in human evolution are a mystery. Current research on the evolution of music has mainly focused on its melodic attribute which would have evolved alongside (proto-)language. Instead, we propose an alternative conceptual framework which focuses on the co-evolution of rhythm and dance (R&D) as intertwined aspects of a multimodal phenomenon characterized by the unity of action and perception. Reviewing the current literature from this viewpoint we propose the hypothesis that R&D have co-evolved long before other musical attributes and (proto-)language. Our view is supported by increasing experimental evidence particularly in infants and children: beat is perceived and anticipated already by newborns and rhythm perception depends on body movement. Infants and toddlers spontaneously move to a rhythm irrespective of their cultural background. The impulse to dance may have been prepared by the susceptibility of infants to be soothed by rocking. Conceivable evolutionary functions of R&D include sexual attraction and transmission of mating signals. Social functions include bonding, synchronization of many individuals, appeasement of hostile individuals, and pre- and extra-verbal communication enabling embodied individual and collective memorizing. In many cultures R&D are used for entering trance, a base for shamanism and early religions. Individual benefits of R&D include improvement of body coordination, as well as painkilling, anti-depressive, and anti-boredom effects. Rhythm most likely paved the way for human speech as supported by studies confirming the overlaps between cognitive and neural resources recruited for language and rhythm. In addition, dance encompasses visual and gestural communication. In future studies attention should be paid to which attribute of music is focused on and that the close mutual relation between R&D is taken into account. The possible evolutionary functions of dance deserve more attention.

A benefit-cost framework of motivation for a specific activity

How can an individual be motivated to perform a target exercise or activity? This question arises in training, therapeutic, and education settings alike, yet despite-or even because of-the large range of extant motivation theories, finding a clear answer to this question can be challenging. Here we propose an application-friendly framework of motivation for a specific activity or exercise that incorporates core concepts from several well-regarded psychological and economic theories of motivation. The key assumption of this framework is that motivation for performing a given activity is determined by the expected benefits and the expected costs of (performance of) the activity. Benefits comprise positive feelings, gains, and rewards experienced during performance of the activity (intrinsic benefits) or achieved through the activity (extrinsic benefits). Costs entail effort requirements, time demands, and other expenditure (intrinsic costs) as well as unwanted associated outcomes and missing out on alternative activities (extrinsic costs). The expected benefits and costs of a given exercise are subjective and state dependent. We discuss convergence of the proposed framework with a selection of extant motivation theories and briefly outline neurobiological correlates of its main components and assumptions. One particular strength of our framework is that it allows to specify five pathways to increasing motivation for a target exercise, which we illustrate and discuss with reference to previous empirical data.

Sensori-Motor Learning with Movement Sonification: Perspectives from Recent Interdisciplinary Studies

This article reports on an interdisciplinary research project on movement sonification for sensori-motor learning. First, we describe different research fields which have contributed to movement sonification, from music technology including gesture-controlled sound synthesis, sonic interaction design, to research on sensori-motor learning with auditory-feedback. In particular, we propose to distinguish between sound-oriented tasks and movement-oriented tasks in experiments involving interactive sound feedback. We describe several research questions and recently published results on movement control, learning and perception. In particular, we studied the effect of the auditory feedback on movements considering several cases: from experiments on pointing and visuo-motor tracking to more complex tasks where interactive sound feedback can guide movements, or cases of sensory substitution where the auditory feedback can inform on object shapes. We also developed specific methodologies and technologies for designing the sonic feedback and movement sonification. We conclude with a discussion on key future research challenges in sensori-motor learning with movement sonification. We also point out toward promising applications such as rehabilitation, sport training or product design.

Increasing self-directed training in neurorehabilitation patients through competition

This proof-of-concept study aimed to test whether competition could be a useful tool to increase intensity and amount of self-directed training in neurorehabilitation. Stroke patients undergoing inpatient neurorehabilitation (n=93) conducted self-directed endurance training on a (wheelchair-compatible) bicycle trainer under three experimental conditions: a "Competition" condition and two noncompetition control conditions (repeated randomized within-subject design). Training performance and perceived exertion were recorded and statistically analyzed. Three motivational effects of competition were found. First, competition led to an increase in self-directed training. Patients exercised significantly more intensively under competition than in the two noncompetition control conditions. Second, (winning a) competition had a positive influence on performance in the subsequent training session. Third, training performance was particularly high during rematch competitions; that is to say, during second encounter competitions against an opponent that the patient had just beaten. No systematic effect of competition upon perceived exertion (controlled for training performance) was found. Together, our results demonstrate that competition is a potent motivational tool to increase self-directed training in neurorehabilitation.

Songs for the Ego: Theorizing Musical Self-Enhancement

This paper outlines a theoretical account of musical self-enhancement. I claim that listening to music serves as a resource for actively manipulating affective states so that a positive self-view is maintained and a sense of optimism is provided. Self-enhancement—the process by which individuals modify their self-worth and gain self-esteem—typically takes place in social interactions. I argue that experiencing music may serve as a unique “esthetic surrogate” for interaction, which equally enables self-enhancement. This ability relies on three main characteristics of the musical experience, namely, its capacity to (a) evoke empathetic feelings, (b) elicit social cohesion and affiliation, and (c) elicit feelings of reward. I outline how these characteristics relate to theories of music cognition and empirical findings in psychology and neuroscience research. I also explain the specifics of musical self-enhancement and how it differs from music’s other regulatory functions such as mood- and emotion regulation. My aim in introducing the notion of musical self-enhancement is to broaden our understanding of how music functions as an environmental resource entailing access to unique affective states and how musical experiences are co-constituted by both the agent and the sonic environment. This specific use of music for self-enhancement can be regarded as a form of affective niche construction, providing the external conditions in which people can experience themselves more positively and maintain high self-esteem.

The E-music box: an empirical method for exploring the universal capacity for musical production and for social interaction through music

Humans are assumed to have a natural-universal-predisposition for making music and for musical interaction. Research in this domain is, however, typically conducted with musically trained individuals, and therefore confounded with expertise. Here, we present a rediscovered and updated invention-the E-music box-that we establish as an empirical method to investigate musical production and interaction in everyone. The E-music box transforms rotatory cyclical movements into pre-programmable digital musical output, with tempo varying according to rotation speed. The user's movements are coded as continuous oscillatory data, which can be analysed using linear or nonlinear analytical tools. We conducted a proof-of-principle experiment to demonstrate that, using this method, pairs of non-musically trained individuals can interact according to conventional musical practices (leader/follower roles and lower-pitch dominance). The results suggest that the E-music box brings 'active' and 'interactive' musical capacities within everyone's reach. We discuss the potential of this method for exploring the universal predisposition for music making and interaction in developmental and cross-cultural contexts, and for neurologic musical therapy and rehabilitation.

Benefits of listening to a recording of euphoric joint music making in polydrug abusers

Background and Aims: Listening to music can have powerful physiological and therapeutic effects. Some essential features of the mental mechanism underlying beneficial effects of music are probably strong physiological and emotional associations with music created during the act of music making. Here we tested this hypothesis in a clinical population of polydrug abusers in rehabilitation listening to a previously performed act of physiologically and emotionally intense music making.

Methods: Psychological effects of listening to self-made music that was created in a previous musical feedback intervention were assessed. In this procedure, participants produced music with exercise machines (Jymmin) which modulate musical sounds.

Results: The data showed a positive effect of listening to the recording of joint music making on self-efficacy, mood, and a readiness to engage socially. Furthermore, the data showed the powerful influence of context on how the recording evoked psychological benefits. The effects of listening to the self-made music were only observable when participants listened to their own performance first; listening to a control music piece first caused effects to deteriorate. We observed a positive correlation between participants’ mood and their desire to engage in social activities with their former training partners after listening to the self-made music. This shows that the observed effects of listening to the recording of the single musical feedback intervention are influenced by participants recapitulating intense pleasant social interactions during the Jymmin intervention.

Conclusions: Listening to music that was the outcome of a previous musical feedback (Jymmin) intervention has beneficial psychological and probably social effects in patients that had suffered from polydrug addiction, increasing self-efficacy, mood, and a readiness to engage socially. These intervention effects, however, depend on the context in which the music recordings are presented.

Familiarity with music increases walking speed in rhythmic auditory cuing

Rhythmic auditory stimulation (RAS) is a gait rehabilitation method in which patients synchronize footsteps to a metronome or musical beats. Although RAS with music can ameliorate gait abnormalities, outcomes vary, possibly because music properties, such as groove or familiarity, differ across interventions. To optimize future interventions, we assessed how initially familiar and unfamiliar low-groove and high-groove music affected synchronization accuracy and gait in healthy individuals. We also experimentally increased music familiarity using repeated exposure to initially unfamiliar songs. Overall, familiar music elicited faster stride velocity and less variable strides, as well as better synchronization performance (matching of step tempo to beat tempo). High-groove music, as reported previously, led to faster stride velocity than low-groove music. We propose two mechanisms for familiarity's effects. First, familiarity with the beat structure reduces cognitive demands of synchronizing, leading to better synchronization performance and faster, less variable gait. Second, familiarity might have elicited faster gait by increasing enjoyment of the music, as enjoyment was higher after repeated exposure to initially low-enjoyment songs. Future studies are necessary to dissociate the contribution of these mechanisms to the observed RAS effects of familiar music on gait.

Synchronized personalized music audio-playlists to improve adherence to physical activity among patients participating in a structured exercise program: a proof-of-principle feasibility study

Background

Preference-based tempo-pace synchronized music has been shown to reduce perceived physical activity exertion and improve exercise performance. The extent to which such strategies can improve adherence to physical activity remains unknown. The objective of the study is to explore the feasibility and efficacy of tempo-pace synchronized preference-based music audio-playlists on adherence to physical activity among cardiovascular disease patients participating in a cardiac rehabilitation.

Methods

Thirty-four cardiac rehabilitation patients were randomly allocated to one of two strategies: (1) no music usual-care control and (2) tempo-pace synchronized audio-devices with personalized music playlists + usual-care. All songs uploaded onto audio-playlist devices took into account patient personal music genre and artist preferences. However, actual song selection was restricted to music whose tempos approximated patients’ prescribed exercise walking/running pace (steps per minute) to achieve tempo-pace synchrony. Patients allocated to audio-music playlists underwent further randomization in which half of the patients received songs that were sonically enhanced with rhythmic auditory stimulation (RAS) to accentuate tempo-pace synchrony, whereas the other half did not. RAS was achieved through blinded rhythmic sonic-enhancements undertaken manually to songs within individuals’ music playlists. The primary outcome consisted of the weekly volume of physical activity undertaken over 3 months as determined by tri-axial accelerometers. Statistical methods employed an intention to treat and repeated-measures design.

Results

Patients randomized to personalized audio-playlists with tempo-pace synchrony achieved higher weekly volumes of physical activity than did their non-music usual-care comparators (475.6 min vs. 370.2 min, P < 0.001). Improvements in weekly physical activity volumes among audio-playlist recipients were driven by those randomized to the RAS group which attained weekly exercise volumes that were nearly twofold greater than either of the two other groups (average weekly minutes of physical activity of 631.3 min vs. 320 min vs. 370.2 min, personalized audio-playlists with RAS vs. personalized audio-playlists without RAS vs. non-music usual-care controls, respectively, P < 0.001). Patients randomized to music with RAS utilized their audio-playlist devices more frequently than did non-RAS music counterparts (P < 0.001).

Conclusions

The use of tempo-pace synchronized preference-based audio-playlists was feasibly implemented into a structured exercise program and efficacious in improving adherence to physical activity beyond the evidence-based non-music usual standard of care. Larger clinical trials are required to validate these findings.

Trial registration

ClinicalTrials.gov ID (NCT01752595)

Electronic supplementary material

The online version of this article (doi:10.1186/s40798-015-0017-9) contains supplementary material, which is available to authorized users.

Encouraging spontaneous synchronisation with D-Jogger, an adaptive music player that aligns movement and music

In this study we explore how music can entrain human walkers to synchronise to the musical beat without being instructed to do so. For this, we use an interactive music player, called D-Jogger, that senses the user's walking tempo and phase. D-Jogger aligns the music by manipulating the timing difference between beats and footfalls. Experiments are reported that led to the development and optimisation of four alignment strategies. The first strategy matched the music's tempo continuously to the runner's pace. The second strategy matched the music's tempo at the beginning of a song to the runner's pace, keeping the tempo constant for the remainder of the song. The third alignment starts a song in perfect phase synchrony and continues to adjust the tempo to match the runner's pace. The fourth and last strategy additionally adjusts the phase of the music so each beat matches a footfall. The first two strategies resulted in a minor increase of steps in phase synchrony with the main beat when compared to a random playlist, the last two strategies resulted in a strong increase in synchronised steps. These results may be explained in terms of phase-error correction mechanisms and motor prediction schemes. Finding the phase-lock is difficult due to fluctuations in the interaction, whereas strategies that automatically align the phase between movement and music solve the problem of finding the phase-locking. Moreover, the data show that once the phase-lock is found, alignment can be easily maintained, suggesting that less entrainment effort is needed to keep the phase-lock, than to find the phase-lock. The different alignment strategies of D-Jogger can be applied in different domains such as sports, physical rehabilitation and assistive technologies for movement performance.

Music and social bonding: "self-other" merging and neurohormonal mechanisms

It has been suggested that a key function of music during its development and spread amongst human populations was its capacity to create and strengthen social bonds amongst interacting group members. However, the mechanisms by which this occurs have not been fully discussed. In this paper we review evidence supporting two thus far independently investigated mechanisms for this social bonding effect: self-other merging as a consequence of inter-personal synchrony, and the release of endorphins during exertive rhythmic activities including musical interaction. In general, self-other merging has been experimentally investigated using dyads, which provide limited insight into large-scale musical activities. Given that music can provide an external rhythmic framework that facilitates synchrony, explanations of social bonding during group musical activities should include reference to endorphins, which are released during synchronized exertive movements. Endorphins (and the endogenous opioid system (EOS) in general) are involved in social bonding across primate species, and are associated with a number of human social behaviors (e.g., laughter, synchronized sports), as well as musical activities (e.g., singing and dancing). Furthermore, passively listening to music engages the EOS, so here we suggest that both self-other merging and the EOS are important in the social bonding effects of music. In order to investigate possible interactions between these two mechanisms, future experiments should recreate ecologically valid examples of musical activities.