Effects of music on depression in older people: a randomised controlled trial

Use of Music Therapy as an Audiological Rehabilitation Tool in the Elderly Population: A Mini-Review

It is well known and documented that sensory perception decreases with age. In the elderly population, hearing loss and reduced vestibular function are among the most prevalently affected senses. Two important side effects of sensory deprivation are cognitive decline and decrease in social participation. Hearing loss, vestibular function impairment, and cognitive decline all lead to a decrease in social participation. Altogether, these problems have a great impact on the quality of life of the elderly. This is why a rehabilitation program covering all of these aspects would therefore be useful for clinicians. It is well known that long-term music training can lead to cortical plasticity. Behavioral improvements have been measured for cognitive abilities and sensory modalities (auditory, motor, tactile, and visual) in healthy young adults. Based on these findings, it is possible to wonder if this kind of multisensory training would be an interesting therapy to not only improve communication but also help with posture and balance, cognitive abilities, and social participation. The aim of this review is to assess and validate the impact of music therapy in the context of hearing rehabilitation in older adults. Musical therapy seems to have a positive impact on auditory perception, posture and balance, social integration, and cognition. While the benefits seem obvious, the evidence in the literature is scarce. However, there is no reason not to recommend the use of music therapy as an adjunct to audiological rehabilitation in the elderly when possible. Further investigations are needed to conclude on the extent of the benefits that music therapy could bring to older adults. More data are needed to confirm which hearing abilities can be improved based on the many characteristics of hearing loss. There is also a need to provide a clear protocol for clinicians on how this therapy should be administered to offer the greatest possible benefits.

Non-pharmacological interventions for older adults with depressive symptoms: a network meta-analysis of 35 randomized controlled trials

Objective: To assess the effectiveness of non-pharmacological interventions for seniors with depressive symptoms.Methods: A comprehensive literature search was performed. We conducted network meta-analysis in two ways, intervention classes (psychosocial, psychotherapy, physical activity, combined, treatment as usual) and individual intervention (11 categories). Whenever included studies used different scales, the different instruments were converted to the units of the scale most frequently used (the Geriatric Depression Scale), such that the effect size was reported as a mean difference (MD) with 95% confidence interval (CI). The risk of bias of RCTs included in this review was assessed according to the Cochrane Handbook. Bayesian NMA was conducted using R-3.4.0 software.Results: A total of 35 RCTs with 3,797 enrolled patients were included. Compared to conventional treatment, physical activity and psychotherapy resulted in significant improvements in depressive symptoms (MD: 2.25, 95%CrI: 0.99-3.56; SUCRA = 86.07%; MD: 1.75, 95% CrI: 0.90-2.64; SUCRA = 66.44%, respectively). Similar results were obtained for music (MD: 2.6; 95% CrI: 0.84-4.35;SUCRA = 80.53%), life review (MD:1.92; 95% CrI:0.71-3.14; SUCRA = 65.62%), cognitive behavioral therapy (MD: 1.27; 95% CrI: 0.23-2.38; SUCRA = 45.4%), aerobic (MD: 1.84; 95% CrI: 0.39-3.36; SUCRA = 63%) and resistance training (MD: 1.72; 95% CrI: 0.06-3.42; SUCRA = 59.24%). Network meta-regression showed that there were no statistically significant subgroup effects.Conclusions: Physical activity and psychotherapy demonstrated statistically significant superiority over conventional treatment. Music and life review therapy proved the most promising individual interventions. However, conclusions are limited by the lack of sufficient sample size and consensus regarding intervention categories and so an adequately powered study is necessary to consolidate these findings.

Incorporating a Usual Care Comparator into a Study of Meditation and Music Listening for Older Adults with Subjective Cognitive Decline: A Randomized Feasibility Trial

BACKGROUND

Recent studies suggest meditation and music listening (ML) may improve cognitive and psychosocial outcomes in adults with subjective cognitive decline (SCD). However, lack of a usual care group has limited conclusions.

OBJECTIVE

To assess the: 1) feasibility of incorporating an enhanced usual care (EUC) comparator in a trial of Kirtan Kriya meditation (KK) and ML for adults experiencing SCD; and 2) preliminary effects of active treatment (KK/ML) versus an EUC program.

METHODS

Forty participants with SCD were randomized 1:1:2 to a 12-week KK, ML, or EUC program. KK and ML participants were asked to practice 12 minutes/day; EUC participants were given a comprehensive educational packet regarding healthy aging and strategies for improving/maintaining brain health and asked to record any activities or strategies used. Feasibility was assessed using measures of retention, adherence, treatment expectancies, and participant satisfaction, as well as information from exit questionnaires and daily practice/activity logs. Cognitive functioning, stress, mood, sleep-quality, and health-related quality of life (QOL) were measured pre- and post-intervention using well-validated instruments.

RESULTS

Thirty-two participants (80%) completed the 3-month study, with retention highest in the EUC group (p < 0.05). Active treatment participants averaged 6.0±0.4 practice sessions/week, and EUC participants, 7.5±0.6 brain health activities/week. Treatment expectancies were similar across groups. EUC participants indicated high satisfaction with the program and study. Despite limited study power, the active treatment group showed significantly greater gains in subjective memory functioning (ps≤0.025) and nonsignificant improvements in cognitive performance (TMT-B), perceived stress, QOL, and mood (ps≤0.08) compared to the EUC group.

CONCLUSION

Findings of this pilot feasibility trial suggest incorporation of an EUC program is feasible, and that participation in a simple 12-week relaxation program may be helpful for adults with SCD versus engagement in an EUC program.

Effects of music therapy on depression: A meta-analysis of randomized controlled trials

Background

We aimed to determine and compare the effects of music therapy and music medicine on depression, and explore the potential factors associated with the effect.

Methods

PubMed (MEDLINE), Ovid-Embase, the Cochrane Central Register of Controlled Trials, EMBASE, Web of Science, and Clinical Evidence were searched to identify studies evaluating the effectiveness of music-based intervention on depression from inception to May 2020. Standardized mean differences (SMDs) were estimated with random-effect model and fixed-effect model.

Results

A total of 55 RCTs were included in our meta-analysis. Music therapy exhibited a significant reduction in depressive symptom (SMD = −0.66; 95% CI = -0.86 to -0.46; P<0.001) compared with the control group; while, music medicine exhibited a stronger effect in reducing depressive symptom (SMD = −1.33; 95% CI = -1.96 to -0.70; P<0.001). Among the specific music therapy methods, recreative music therapy (SMD = -1.41; 95% CI = -2.63 to -0.20; P<0.001), guided imagery and music (SMD = -1.08; 95% CI = -1.72 to -0.43; P<0.001), music-assisted relaxation (SMD = -0.81; 95% CI = -1.24 to -0.38; P<0.001), music and imagery (SMD = -0.38; 95% CI = -0.81 to 0.06; P = 0.312), improvisational music therapy (SMD = -0.27; 95% CI = -0.49 to -0.05; P = 0.001), music and discuss (SMD = -0.26; 95% CI = -1.12 to 0.60; P = 0.225) exhibited a different effect respectively. Music therapy and music medicine both exhibited a stronger effects of short and medium length compared with long intervention periods.

Conclusions

A different effect of music therapy and music medicine on depression was observed in our present meta-analysis, and the effect might be affected by the therapy process.

Testing a Musical Game Activity for Community-Dwelling Older Adults

Leisure programs that combine music with active leisure activities are more common than music combined with passive activities. The latter offers alternatives for older adults with health declines. The purpose of this pilot study was to determine the effect of an innovative song bingo game on mood, satisfaction, and acceptability in community-residing older adults. The design was quasi-experimental. A convenience sample of 13 older adults (mean age = 74.4; 53.8% female, 38.5% black) were recruited from a community senior center. The intervention was an innovative song bingo program offered one time with staff assistance. A song list was created from age-appropriate music. Measures included a demographic survey, mood scale, and satisfaction and acceptability items. Data analysis was performed to compute descriptive items and compare mean mood scores before and after the program. Before the program, 33.4% of the participants reported their mood as “very happy” or “happy.” Afterwards, 61.5% reported their mood was either “very happy” or “happy.” When comparing the preprogram and postprogram mean mood scores, mean values increased from 5.0 (standard deviation [ SD] = 1.0) to 5.7 ( SD = 1.4), although the difference was not statistically significant ( t = −1.8, p = .09). Overall participants were satisfied and would play again. This program was cost-effective and improved mood in community-dwelling older adults. Replicating this study in a larger sample and different settings is recommended.

Detection of Music Preferences using Cerebral Blood Flow Signals

Music has been used for entertainment as well as for medical treatments that remedies physical conditions or psychiatric disorders. It is reported that better outcome can be expected when the music was selected along with personal preferences for these therapies. However it is difficult to find out personalized favorite music if the patient has difficulty in verbal communication due to ageing or developmental disorders. Therefore, this study aimed to develop an objective classification method of music preference based on cortical hemodynamic activities upon listening to the music clips. Fifteen healthy young adults listened their favorite and non-favorite music with their cortical activity measured with 38-channel functional near infrared spectroscopy (fNIRS). Eleven features were extracted from the time-courses of fNIRS signals from the left primary auditory area, the superior temporal gyrus, and the subcentral area. One- to four- dimensional features were individually selected using a leave-one-out cross-validation with two classification algorithms of Fisher linear discriminant analysis (LDA) and support vector machine. The best mean accuracy rate of 92.2 ± 1.7% was obtained when an LDA classifier with four features derived from oxy-hemoglobin signals were adopted showing that our proposed method is valid to classify individual music preference.

Effectiveness of integrative medicine program for dementia prevention on cognitive function and depression of elderly in a public health center

Background

This study investigated the effectiveness of an integrative medicine program (IMP) for dementia prevention on cognitive function, depression and quality of life (QOL) of elderly in a public health center.

Methods

This study employed a before-after study design to assess effectiveness of the IMP for dementia prevention for community dwelling elderly over 60 without diagnosis of dementia. Cognitive function was measured using the Mini Mental State Examination for Dementia screening (MMSE-DS), digit span test (DST) and trail making test (TMT). The Geriatric Depression Scale Short Form- Korean version (GDSSF-K) and EQ-5D were used to evaluate depression and health-related quality of life. The IMP composed of acupuncture, moxibustion, physical activities, meditation, laughter therapy and music therapy was held once a week over 8 weeks. A paired t-test was used to compare the pre and post-test results.

Results

After screening 93 people, a total of 48 were included in the analysis. Evaluation of the cognitive function revealed that TMT-A (p = 0.028) and TMT-B (p = 0.0013) were significantly reduced, but MMSE-DS (p = 0.309) and DST (DSF: p = 0.855, DSB: p = 0.176) were not statistically significant. Depression (p < 0.01) and preventive behavior for dementia (p < 0.0001) of the participants were improved after the IMP.

Conclusion

The IMP for dementia prevention may have beneficial effects on cognitive function and depression of elderly. However, a well-designed follow-up study is needed to confirm this conclusion.

Decreased risk of falls in patients attending music sessions on an acute geriatric ward: results from a retrospective cohort study

Background

Music has been shown to improve health and quality of life. It was suggested that music may also have an impact on gait stability and fall risk. Yet, few studies have exploited music in the hospital setting, and even less so in the geriatric population. Our objective was to examine the influence of music listening on the risk of falls by comparing the Morse Fall Scale score in patients admitted to a Geriatric Assessment Unit (GAU) who attended music listening sessions and in patients who did not attend music sessions.

Methods

This was a retrospective cohort study (mean follow-up 13.3 ± 6.8 days) which took place in a GAU, St. Mary’s Hospital Center, Montreal. A total of 152 charts of participants, with a mean age of 85.7 ± 6.4 years and 88.2% female were reviewed and included. There were 61 participants exposed to the music listening sessions group and 91 in the non-exposed group matched for age, sex, cause and season of admission, and living situation. One-hour music sessions were provided to the patients by volunteer musicians. The Morse Fall Scale score upon admission and discharge as well as its variation (change from before to after exposure) were used as outcomes. Age, sex, living situation, reason for admission, season of admission, Mini Mental Status Examination score, number of therapeutic classes taken daily upon admission, use of psychoactive drugs upon admission and length of stay were used as covariates.

Results

The Morse Fall Scale score decreased significantly in the exposed group compared to the non-exposed group (p = 0.025) and represented a small to medium-sized effect, d = 0.395. The multiple linear regression model showed a significant association between the decrease of the Morse Fall Scale score and music exposure (B = − 17.1, p = 0.043).

Conclusion

Participating in music listening sessions was associated with a decreased risk of falls in patients admitted to a GAU. Further controlled research is necessary to confirm these findings and to determine the mechanisms by which music listening impacts fall risk.

Trial registration

Clinical trial registry: ClinicalTrials.gov. Registration number: NCT03348657 (November 17th, 2017). Retrospectively registered.

Individuals with more severe depression fail to sustain nucleus accumbens activity to preferred music over time

We investigated the ability of preferred classical music to activate the nucleus accumbens in patients with Major depressive disorder (MDD). Twelve males with MDD and 10 never mentally ill male healthy controls (HC) completed measures of anhedonia and depression severity, and listened to 90-second segments of preferred classical music during fMRI. Compared to HCs, individuals with MDD showed less activation of the left nucleus accumbens (NAcc). Individuals with MDD showed attenuation of the left NAcc response in later compared to earlier parts of the experiment, supporting theories that MDD involves an inability to sustain reward network activation. Counter intuitively, we found that NAcc activity during early music listening was associated with greater depression severity. In whole-brain analyses, anhedonia scores predicted activity in regions within the default mode network, supporting previous findings. Our results support theories that MDD involves an inability to sustain reward network activation. It also highlights that pleasant classical music can engage critical neural reward circuitry in MDD.

The Impact of Combined Music and Tai Chi on Depressive Symptoms Among Community-Dwelling Older Persons: A Cluster Randomized Controlled Trial

BACKGROUND

The effectiveness of pharmacological treatment may be limited in older persons. Several studies using Tai Chi or music therapy separately confirmed positive effects in the reduction of depressive symptoms. We conducted a cluster randomized controlled trial to evaluate the possible synergistic effect of combined music and Tai Chi on depressive symptoms.

METHODS

One hundred and seven older adults with mild to moderate depressive symptoms were recruited from Ya'an city. Fifty-five participants were cluster randomized to combined music and Tai Chi group for three months, while the other fifty-two individuals were randomized to the control group that entailed routine health education delivered monthly by community nurses. The primary outcome of depressive symptoms was measured with the Geriatric Depression Scale (GDS) at baseline and monthly for three months.

RESULTS

At three-month follow-up, a statistically significant improvement in depressive symptoms was found in the intervention group compared with control group (F(3,315) = 69.661, P < 0.001). Following adjustments for socio-demographic data, the true effect of intervention on depressive symptoms was significant (F = 41.725, P < 0.01, η_p² = 0.574).

CONCLUSIONS

Combined music and Tai Chi reduced depressive symptoms among community-dwelling older persons. This represents an economically viable solution to the management of depression in highly populous developing nations.

The effect of music therapy on depression and physiological parameters in elderly people living in a Turkish nursing home: a randomized-controlled trial

OBJECTIVE

This study was carried out in an effort to determine the effect of music therapy on depression and physiological parameters in elderly people who were living in a nursing home.

METHOD

The study was a randomized controlled trial. The study sample consisted of 64 elderly people who complied with the criteria of inclusion for the study. The data were collected using the 'Elderly Information Form' and 'Geriatric Depression Scale'. The music group listened to music three days in a week during 8 weeks. The depression levels were assessed at baseline (week 0) and follow-up in the eight week.

RESULTS

It was found that the difference between post-test depression scores of the two groups was found to be statistically significant (t = -2.86, p <.01). The mean scores of post-test systolic blood pressure in the music group were found to be significantly lower than those of the control group (t = -3.11, p < .05).

CONCLUSION

It was concluded that music therapy decreased the depression level and systolic blood pressure in elderly people. The study results implies that music therapy can be an effective practice for public health and home care nurses attempting to reduce depression and control physiological parameters of elderly people.

What works for wellbeing? A systematic review of wellbeing outcomes for music and singing in adults

Aims:

The role of arts and music in supporting subjective wellbeing (SWB) is increasingly recognised. Robust evidence is needed to support policy and practice. This article reports on the first of four reviews of Culture, Sport and Wellbeing (CSW) commissioned by the Economic and Social Research Council (ESRC)-funded What Works Centre for Wellbeing (https://whatworkswellbeing.org/).

Objective:

To identify SWB outcomes for music and singing in adults.

Methods:

Comprehensive literature searches were conducted in PsychInfo, Medline, ERIC, Arts and Humanities, Social Science and Science Citation Indexes, Scopus, PILOTS and CINAHL databases. From 5,397 records identified, 61 relevant records were assessed using GRADE and CERQual schema.

Results:

A wide range of wellbeing measures was used, with no consistency in how SWB was measured across the studies. A wide range of activities was reported, most commonly music listening and regular group singing. Music has been associated with reduced anxiety in young adults, enhanced mood and purpose in adults and mental wellbeing, quality of life, self-awareness and coping in people with diagnosed health conditions. Music and singing have been shown to be effective in enhancing morale and reducing risk of depression in older people. Few studies address SWB in people with dementia. While there are a few studies of music with marginalised communities, participants in community choirs tend to be female, white and relatively well educated. Research challenges include recruiting participants with baseline wellbeing scores that are low enough to record any significant or noteworthy change following a music or singing intervention.

Conclusions:

There is reliable evidence for positive effects of music and singing on wellbeing in adults. There remains a need for research with sub-groups who are at greater risk of lower levels of wellbeing, and on the processes by which wellbeing outcomes are, or are not, achieved.

Reviewing the Effectiveness of Music Interventions in Treating Depression

Depression is a very common mood disorder, resulting in a loss of social function, reduced quality of life and increased mortality. Music interventions have been shown to be a potential alternative for depression therapy but the number of up-to-date research literature is quite limited. We present a review of original research trials which utilize music or music therapy as intervention to treat participants with depressive symptoms. Our goal was to differentiate the impact of certain therapeutic uses of music used in the various experiments. Randomized controlled study designs were preferred but also longitudinal studies were chosen to be included. 28 studies with a total number of 1,810 participants met our inclusion criteria and were finally selected. We distinguished between passive listening to music (record from a CD or live music) (79%), and active singing, playing, or improvising with instruments (46%). Within certain boundaries of variance an analysis of similar studies was attempted. Critical parameters were for example length of trial, number of sessions, participants' age, kind of music, active or passive participation and single- or group setting. In 26 studies, a statistically significant reduction in depression levels was found over time in the experimental (music intervention) group compared to a control (n = 25) or comparison group (n = 2). In particular, elderly participants showed impressive improvements when they listened to music or participated in music therapy projects. Researchers used group settings more often than individual sessions and our results indicated a slightly better outcome for those cases. Additional questionnaires about participants confidence, self-esteem or motivation, confirmed further improvements after music treatment. Consequently, the present review offers an extensive set of comparable data, observations about the range of treatment options these papers addressed, and thus might represent a valuable aid for future projects for the use of music-based interventions to improve symptoms of depression.

Dancing for Parkinson Disease: A Randomized Trial of Irish Set Dancing Compared With Usual Care

OBJECTIVE

To examine the feasibility of a randomized controlled study design and to explore the benefits of a set dancing intervention compared with usual care.

DESIGN

Randomized controlled design, with participants randomized to Irish set dance classes or a usual care group.

SETTING

Community based.

PARTICIPANTS

Individuals with idiopathic Parkinson disease (PD) (N=90).

INTERVENTIONS

The dance group attended a 1.5-hour dancing class each week for 10 weeks and undertook a home dance program for 20 minutes, 3 times per week. The usual care group continued with their usual care and daily activities.

MAIN OUTCOME MEASURES

The primary outcome was feasibility, determined by recruitment rates, success of randomization and allocation procedures, attrition, adherence, safety, willingness of participants to be randomized, resource availability, and cost. Secondary outcomes were motor function (motor section of the Unified Parkinson's Disease Rating Scale), quality of life (Parkinson's Disease Questionnaire-39), functional endurance (6-min walk test), and balance (mini-BESTest).

RESULTS

Ninety participants were randomized (45 per group). There were no adverse effects or resource constraints. Although adherence to the dancing program was 93.5%, there was >40% attrition in each group. Postintervention, the dance group had greater nonsignificant gains in quality of life than the usual care group. There was a meaningful deterioration in endurance in the usual care group. There were no meaningful changes in other outcomes. The exit questionnaire showed participants enjoyed the classes and would like to continue participation.

CONCLUSIONS

For people with mild to moderately severe PD, set dancing is feasible and enjoyable and may improve quality of life.

Effects of Meditation versus Music Listening on Perceived Stress, Mood, Sleep, and Quality of Life in Adults with Early Memory Loss: A Pilot Randomized Controlled Trial

BACKGROUND

Older adults with subjective cognitive decline (SCD) are at increased risk not only for Alzheimer's disease, but for poor mental health, impaired sleep, and diminished quality of life (QOL), which in turn, contribute to further cognitive decline, highlighting the need for early intervention.

OBJECTIVE

In this randomized controlled trial, we assessed the effects of two 12-week relaxation programs, Kirtan Kriya Meditation (KK) and music listening (ML), on perceived stress, sleep, mood, and health-related QOL in older adults with SCD.

METHODS

Sixty community-dwelling older adults with SCD were randomized to a KK or ML program and asked to practice 12 minutes daily for 12 weeks, then at their discretion for the following 3 months. At baseline, 12 weeks, and 26 weeks, perceived stress, mood, psychological well-being, sleep quality, and health-related QOL were measured using well-validated instruments.

RESULTS

Fifty-three participants (88%) completed the 6-month study. Participants in both groups showed significant improvement at 12 weeks in psychological well-being and in multiple domains of mood and sleep quality (p's≤0.05). Relative to ML, those assigned to KK showed greater gains in perceived stress, mood, psychological well-being, and QOL-Mental Health (p's≤0.09). Observed gains were sustained or improved at 6 months, with both groups showing marked and significant improvement in all outcomes. Changes were unrelated to treatment expectancies.

CONCLUSIONS

Findings suggest that practice of a simple meditation or ML program may improve stress, mood, well-being, sleep, and QOL in adults with SCD, with benefits sustained at 6 months and gains that were particularly pronounced in the KK group.

Effects of relaxation interventions on depression and anxiety among older adults: a systematic review

OBJECTIVES

This systematic review examined empirical evidence of the effects of relaxation interventions on anxiety and depression among older adults.

METHOD

A comprehensive literature search identified studies that satisfied the pre-set inclusion and exclusion criteria. We focused on 15 published and non-published studies - 12 randomised controlled trials and three non-randomised controlled trials - undertaken in the past 20 years (1994-2014). Three reviewers selected studies, extracted data, and appraised the methodological quality. We then computed Hedges' effect sizes and used these to represent the effects of intervention.

RESULTS

Our findings suggested that older adults who received relaxation interventions experienced greater reductions in depression and anxiety than controls in most studies. Progressive muscle relaxation training, music intervention, and yoga had the strongest intervention effects on depression. Music intervention, yoga, and combined relaxation training most effectively reduced anxiety symptoms among older adults. Furthermore, the impact of some relaxation interventions remained in effect for between 14 and 24 weeks after the interventions.

CONCLUSION

This systematic review supported the positive effects of relaxation interventions on depression and anxiety among older adults. Health care providers may integrate relaxation interventions into standard care for older adults in community and hospital settings, taking into consideration the participant's preference and health care policy.

[Cognitive stimulation and music intervention for people with dementia in nursing homes: A pilot study, problems and perspectives]

BACKGROUND

Nonpharmacological interventions in people with dementia are becoming an increasingly important addition to pharmacological therapy. However, the current state of research in this field is limited.

OBJECTIVES

The aim of this pilot study was to evaluate the effects of a cognitive stimulation program and a music intervention program on cognitive function, quality of life and activities of daily living in persons with dementia residing in nursing homes. In addition, specific challenges of randomized controlled trials in nursing homes should be identified to define recommendations for further studies.

METHODS

Over a period of 6 weeks, 24 individuals with mild to moderate dementia were randomly allocated to participation in a cognitive stimulation program or in a music intervention. Each program consisted of twelve group-sessions of 90 min with two sessions per week. A neuropsychological test battery was performed before and after the training period.

RESULTS

There were no significant improvements on the group level. In fact, performance declined in some domains. Nonetheless, heterogeneous results were evident in both groups after analysis on a single-case approach and some persons significantly improved their performance.

CONCLUSION

At least on a single-case approach, the study provides additional support for the potential of nonpharmacological interventions. Future studies should target logistical aspects in nursing homes, realistic planning of sample size, formulating adequate inclusion and exclusion criteria, and choosing suitable neuropsychological tests.

Variability in prefrontal hemodynamic response during exposure to repeated self-selected music excerpts, a near-infrared spectroscopy study

Music-induced brain activity modulations in areas involved in emotion regulation may be useful in achieving therapeutic outcomes. Clinical applications of music may involve prolonged or repeated exposures to music. However, the variability of the observed brain activity patterns in repeated exposures to music is not well understood. We hypothesized that multiple exposures to the same music would elicit more consistent activity patterns than exposure to different music. In this study, the temporal and spatial variability of cerebral prefrontal hemodynamic response was investigated across multiple exposures to self-selected musical excerpts in 10 healthy adults. The hemodynamic changes were measured using prefrontal cortex near infrared spectroscopy and represented by instantaneous phase values. Based on spatial and temporal characteristics of these observed hemodynamic changes, we defined a consistency index to represent variability across these domains. The consistency index across repeated exposures to the same piece of music was compared to the consistency index corresponding to prefrontal activity from randomly matched non-identical musical excerpts. Consistency indexes were significantly different for identical versus non-identical musical excerpts when comparing a subset of repetitions. When all four exposures were compared, no significant difference was observed between the consistency indexes of randomly matched non-identical musical excerpts and the consistency index corresponding to repetitions of the same musical excerpts. This observation suggests the existence of only partial consistency between repeated exposures to the same musical excerpt, which may stem from the role of the prefrontal cortex in regulating other cognitive and emotional processes.

Mozart, music and medicine

According to the first publication in 1993 by Rauscher et al. [Nature 1993;365:611], the Mozart effect implies the enhancement of reasoning skills solving spatial problems in normal subjects after listening to Mozart's piano sonata K 448. A further evaluation of this effect has raised the question whether there is a link between music-generated emotions and a higher level of cognitive abilities by mere listening. Positron emission tomography and functional magnetic resonance imaging have revealed that listening to pleasurable music activates cortical and subcortical cerebral areas where emotions are processed. These neurobiological effects of music suggest that auditory stimulation evokes emotions linked to heightened arousal and result in temporarily enhanced performance in many cognitive domains. Music therapy applies this arousal in a clinical setting as it may offer benefits to patients by diverting their attention from unpleasant experiences and future interventions. It has been applied in the context of various important clinical conditions such as cardiovascular disorders, cancer pain, epilepsy, depression and dementia. Furthermore, music may modulate the immune response, among other things, evidenced by increasing the activity of natural killer cells, lymphocytes and interferon-γ, which is an interesting feature as many diseases are related to a misbalanced immune system. Many of these clinical studies, however, suffer from methodological inadequacies. Nevertheless, at present, there is moderate but not altogether convincing evidence that listening to known and liked music helps to decrease the burden of a disease and enhances the immune system by modifying stress.