Dementia is a broad category of persistent disease which results in deficits in memory, personality, emotional expression and reasoning.(74) Dementia is a broad category of neurodegenerative disease including Alzheimer’s disease and Creutzfeldt-Jakob Disease(75). Alzheimer’s disease results from a buildup of beta-amyloid protein(76) leading to nerve cell damage(77). As an estimate, around 670 000 people in the United Kingdom have dementia.(78)
A study of 48 dementia and Alzheimer’s disease patients found that singing 'improves mood, behaviour and cognitive functioning' in people with dementia.(79) This study’s reliability was increased by the fact that it used a control activity of cooking(80) and this is significant as on the whole, not enough music therapy trials use a comparable control activity.(81) In addition, each intervention lasted for four weeks(82) which, although not longitudinal, is a fair amount of time. Whilst no cognitive effect resulted from the study(83), it improved the ‘wellbeing’ of dementia patients and reduced ‘caregiver distress’.(84)
Another similar study found that ‘musical intervention’, especially ‘active musical intervention’ (for example playing an instrument), was beneficial in reducing stress in moderate to severe dementia patients.(85) Although this was a small sample size of 39 individuals(86), the researchers used the widely recognised ‘Behavioral Pathology in Alzheimer's Disease (BEHAVE-AD) Rating Scale’(87) and credit must be given as they assessed music therapy in patients with severe forms of dementia, whereas most studies only examine mild dementia.(88)
Researchers using a larger sample size of 89 elderly patients with early dementia found that both listening to and singing music improved ‘mood’, sense of direction and memory.(89) It also resulted in smaller positive increases in ‘attention, executive function, and general cognition'.(90) What also increased reliability in said study was that patients were assigned randomly to the music therapy group to prevent bias(91) and the researchers used a standard care control.(92) Therefore we can see that there is a fair amount of evidence to suggest music improves the quality of life of dementia patients.
In a small-scale study of 38 patients with Alzheimer-type dementia, research showed that there is a reduction in ‘depression and agitation’ in dementia patients both during and after music therapy.(93) This study, unfortunately, did not control for casual interaction with music in the patients’ everyday lives, which may have altered results.(94) However, the study included a two-week baseline ‘no music’ period before the trial, demonstrated ‘rapid and sustained’ results and lasted for a total of 12 weeks(95) so results were statistically significant.
Although the aforementioned study of 48 patients showed no cognitive results in dementia patients, two studies show the contrary. In the first study, cognitive assessment was via the ‘Mini-Mental State Examination (MMSE)’ and language ability through the ‘Western Aphasia Battery (WAB)’*.(96) These increase the reliability of the results. The results from 20 participants show that music therapy ‘significantly improves’ performance in ‘speech content and fluency’(97), which is clinically important as this could ‘enhance communication’ between caregivers and patients.(98) However, the overall Aphasia Quotient (AQ, aphasia meaning ability to speak) was not statistically significant(99), which means that further research should be done in this area. The second study showed that the language subscale of the Mini-Mental State Examination (MMSE) improved ‘significantly’.(100)
On the ‘Multidimensional Observation Scale For Elderly Subjects (MOSES)’, the ‘irritability’ scores ‘decreased significantly’.(101) ‘Salivary chromogranin A (CgA) level’, an endocrinological marker of stress, was ‘significantly decreased’ after music therapy.(102) This shows us that music therapy significantly affects the endocrine system and behaviour in positive ways. Considering this study was very small in sample size (ten) and not recent (2004)(103), more large-scale recent research needs to be conducted. However, we can see that music therapy can appreciably improve dementia patients’ quality of life.
Depression is a mental illness characterised by a lack of serotonin resulting in a persistent low mood, also affecting brain regions like the amygdala.(104) In a small-scale study of ten volunteers, researchers used ‘positron emission tomography’ (PET) scanning - a type of brain scan using radioactive tracing - to examine blood flow to the brain (cerebral blood flow, CBF).(105) They showed that music activated both limbic and paralimbic systems, complex neural networks associated with mood and instinct, including the amygdala.(106) In another small-scale study again using positron emission tomography scanning, scientists found that “chills” resulting from music activated regions associated with positive emotions.(107) Despite the fact that these are older small-scale studies, there is ‘significant’ potential for music to help with the alleviation of symptoms of disorders of amygdala dysfunction such as depression.(108)
From a more behavioural standpoint, a randomised control trial for the treatment of depression through music therapy showed improvements in depression, anxiety and ‘general functioning’ symptoms at a 3-month follow-up following prolonged music therapy.(109) The researchers found no statistical difference in the quality of life and alexithymia (inability to describe own emotions) categories, contradictory to later research - this study is from 2011. Also, the study was large with 79 patients(110), unlike the other small-scale studies. There was a greater improvement of symptoms in patients participating in both music and standard therapy than standard therapy alone(111), suggesting that a combination of music therapy and standard care is most effective in treating depression.
As we have also seen previously, music therapy can not only help reduce levels of depression in clinically depressed patients but also reduce these symptoms in patients with dementia too.(112) Similarly, a study of 15 stroke patients found that those who learned the piano by responding to delayed music tones showed fewer depression symptoms than those who learned without delay.(113) This makes sense as the anticipation present in music is associated with the activation of the amygdala and similar regions and this area has been well-researched.(114)
In addition, as depression is associated with low levels of the neurotransmitters serotonin and dopamine(115), the relationship between music and these two chemicals is of clinical interest. In a large-scale study, scientists found that levels of serotonin increased significantly whilst healthy patients listened to ‘pleasant’ music.(116) Assessing neurotransmission of serotonin may be more useful when investigating depression as this is a more objective criteria than emotional response scales. In an often-cited study, patients showed a dramatic increase in dopamine levels both before and during music listening, with distinct forms of dopamine for both criteria.(117) Whilst the exact number of participants is not detailed, the methodology was quite rigorous with controls and the use of positron emission tomography (PET) scanning(118), increasing the reliability of the data.
Many older patients do not regard depression as seriously as younger patients(119) which has led to research into music therapy for treatment of depression in older adults. One randomised-control study of 47 elderly people with controls found that there was ‘statistically significant’ decreases in depression scores, blood pressure, heart rate and respiratory rate after one month.(120) Another randomised-control study of 50 older adults (26 control) showed a ‘significant reduction in depression levels’ over the course of music therapy.(121) This demonstrates that there is substantial evidence that music therapy can be beneficial in improving the symptoms of depression in a wide variety of patients.
Heart disorders are a broad category of illness featuring a malfunction of the heart. The autonomic effects of music can help to decrease the variability of heart rate - useful when treating conditions with irregular heart rate, called arrhythmia.(122) In a large sample size group of 87 students preparing for a stressful event (a presentation) with and without music, the ‘significant’ increase in ‘heart rate, blood pressure, cortisol and salivary IgA’ associated with the presentation was prevented by music.(123) This was a study that went to great depths to ensure certainty and reliability of data by using rigorous controls and in addition used very objective assessment criteria.(124) This has a therapeutic potential with regards to treating arrhythmia associated with heart disease. In addition, given that ischemic heart disease is strongly linked to high blood pressure levels (hypertension)(125), the blood pressure-reducing effects of music can help prevent the development of heart disease.
In a study of 138 healthy patients and 19 with Crohn’s disease, heart rate variability (the variation in time between heartbeats) decreased when listening to music, even if the music was atonal or unpleasant.(126) This study also used a control and measured objectively, although there are not enough studies of this nature. This effect is clinically relevant when discussing the variability in heart rate associated with poor breathing capacity due to heart disease. This also shows that music’s effect is so potent that the likeability of the music does not matter in this case, unlike more emotional responses like anxiety.(127)
The reason for this is because music affects the autonomic nervous system (ANS), whose malfunction is very linked to heart disorders, sudden death and heart failure.(128) Unfortunately, the literature on the relationship between music therapy and individuals with autonomic nervous system dysfunction is limited. In a study of 16 singers with eight amateurs, researchers found that although arousal increased more in the professional singers than amateurs, the latter had greater positive autonomic nervous system effects from singing.(129) Although this was a small- scale study (with good controls and assessment), it does highlight how music therapy could be clinically significant with regards to autonomic nervous system-related heart disease.
Another factor to consider is the relationship between anxiety and/or depression and heart disorder. Given that patients with early-onset depression have a risk 1.5 to 2 times greater than the average population for the development of heart disorder(130), music therapy’s ability to alleviate depression symptoms can also be considered clinically significant with regards to heart disease. This is consistent with scientific evidence as in a randomised-control trial of 40 patients who underwent ‘open coronary artery bypass’ and/or ‘aortic valve replacement’ surgery, those who listened to music during bed rest had an increase in levels of oxytocin release.(131) However, this study found no decrease in blood pressure or heart rate, although this is an older study with the inclusion of subjective (as well as objective) assessment criteria.(132)
Overall, there is strong clinical data to suggest that music therapy is beneficial in both preventing and treating heart disease, particularly symptoms of high blood pressure, heart rate variability, heart rate and increased hormonal markers of stress.
© 2017 Nat Barrett. Published by teoria.com