New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...
The Neurochemistry of Music
1. The Neurochemistry of Music
Mona Lisa Chanda and Daniel J. Levitin
Trends in Cognitive Science, 2013
2. Why I chose this paper?
▹ Opportunity:
▸ Knowledge gain and personal benefit (health)
▸ Research opportunities (natural language processing to neuroimaging)
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Topic: Multimedia recommendation (music) for mental disorder patients (offline
and online environment).
3. Housekeeping
What is Neurochemistry?
1. “The chemistry of the brain.”
1. “Neurochemistry is the specific study of neurochemicals, including
neurotransmitters and other molecules … that influence the function of
neurons.” - Wikipedia
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5. Introduction
How is music used as a medicine?
▹ General: regulate mood and arousal, enhance concentration, improve
attention, and increase stamina and motivation
▹ Clinical setting: pain management, relaxation, psychotherapy, and
personal growth.
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There is need to scientifically prove whether music can influence health by
observing specific neurochemical changes in the brain.
6. Objective
More formally, the objective is to evaluate whether music improves health
through engagement of neurochemical systems in charge of the following four
domains:
▹ Reward, motivation, and pleasure → dopamine and opioids
▹ Stress and arousal → cortisol
▹ Immunity → serotonin
▹ Social affiliation → oxytocin
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7. Limitations of current literature
▹ The heterogeneity (diversity) of methods
▸ Selection of music stimuli not standardized yet (lead to
inconsistencies)
▸ Lack of adequate nonmusical control conditions (e.g., audiobooks)
▹ Concerns on music Interventions: Type of intervention (passive vs active),
type of music (stimulating vs relaxing), locus of control (experimenter vs
participant), and social context (individual vs group)
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9. Reward, motivation, and pleasure
Reward is a complex construct involving motivational states, prediction, goal-
directed behaviour, reinforcement learning, and hedonic (pleasurable) states
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In terms of the neural network, does music achieve similar characteristics as other
rewarding experiences, such as drugs, food, and sex ?
10. Reward, motivation, and pleasure - (Initial Findings)
▹ Music produces intense pleasure and euphoria [15,16].
▹ Music doesn’t have a clear survival benefit such as food.
Some deem music as having mystical powers and
cannot be explained by simply studying neurochemical
states [22,23].
▹ Hope: Advances in cognitive neuroscience claim that
music affects the same neurochemical systems of reward
as other reinforcing stimuli.
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12. Reward, motivation, and pleasure - (Neurobiology)
Mesocorticolimbic system is responsible
for reward, motivation, learning, memory,
and movement.
▹ Mesolimbic pathway
▸ VTA → NAc
▸ Reward-related cognition
▹ Mesocortical pathway
▸ VTA → Prefrontal cortex
▸ Cognitive control of behaviour VTA=Ventral tegmental area
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Source: https://courses.washington.edu
13. Reward, motivation, and pleasure - (Summarized findings)
Positron Emission Technology (PET)
▹ Self-selected, chill music → increased regional cerebral blood flow (rCBF)
within the midbrain (ventral striatum) [28]
▹ Experimenter-selected music, pleasurable music → activation of NAc and
opioid-rich midbrain [29]
Functional Magnetic Resonance Imaging (fMRI)
▹ Pleasurable music → strong connectivity between NAc and VTA; suggests that
musical reward is dependent on dopaminergic neurotransmission within a
similar neural network as other reinforcing stimuli [31]
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15. Reward, motivation, and pleasure - (Summarized findings)
▹ Due to low spatial resolution of PET, it was not possible to precisely localize
activity within the regions involved in reward processing.
▹ PET and fMRI couldn’t directly investigate dopamine release during the
process of musical reward, therefore, relying on a proxy for neuronal
activation.
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16. Reward, motivation, and pleasure - (Recommendations)
▹ Better control conditions consisting of neutral music and pleasurable non-
music control stimulus (e.g., desirable food, books, and television show)
▹ Computer-based real-time ratings of subjective pleasure states.
▹ Monitoring physiological responses to music (e.g., heart rate, blood volume
pulse, body temperature, etc.)
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19. Stress and arousal - (Neurobiology)
Stress response occurs in the loss of homeostatic equilibrium, where there are
various systems working together to restore physical and psychological balance.
These systems include neurochemicals such as cortisol (regulate metabolism and
immune function), epinephrine, hypothalamic hormones, serotonin, among
others.
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Long period of stress may lead to chronic activation of these systems which in turn
has detrimental consequences for health.
21. Stress and arousal - (Findings)
‘Relaxing music’ was shown to reduce stress and anxiety in healthy subjects and
patients undergoing invasive medical procedures (colonoscopy, dental
procedures)[49, 52].
Guided Imagery and Music (GIM) reduced hypothalamic-pituitary-adrenal (HPA)
activation, specifically the cortisol and endorphin markers. Furthermore, both
strategies had to be used and music alone showed no activation [59, 60].
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22. Stress and arousal - (Findings)
Stimulating music (techno) increased activation in many markers and also
those of HPA [62,63].
Cardiovascular measures, such as heart rate and blood pressure, were also used
to measure effect of music in regulating stress. Stimulating music increased
these measures while slow tempo music decreased these measures [75].
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23. Stress and arousal - (Locus of control)
▹ There was a decrease in cortisol levels of patients that self-selected music as
compared to experimenter-selected music [84].
▹ Post-surgery patients experienced significantly lower pain, anxiety and blood
pressure when they were allowed to self-select the genre of music [85].
▹ The timing the music was delivered may also have an effect on the
experiments. That said, it is also important to track psychophysiological state
prior to music listening.
▹ In another experiment it was observed that professional music therapy was
more beneficial than drug intake [88].
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24. Stress and arousal - (Recommendations)
Personality factors: Music perception and cognition are subjective; thus, future
studies would benefit from having participants rate the arousal properties and
emotional dimensions of music.
Bias: It would also help to isolate the effects of music itself from other possible
factors, such as distractions.
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26. Immunity
▹ The immune system has two line of defenses, namely the innate and
adaptive system.
▹ Stress and aging can have detrimental effects on both systems.
▹ Stimuli eliciting positive emotions may help mitigate the negative effects of
age and stress on the immunity system [92, 93].
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Assumption: Music enhances mood and reduce stress levels, therefore it might be
able to improve immune function [51].
27. Immunity - (Group drumming circles)
Recreational music-making has been used to improve mood and reduce stress
among the elderly [94].
Group drumming requires no expertise, therefore makes it a creative process. It
is also mixed with imagery and social interaction among group members.
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29. Immunity - (Findings)
The impact of group drumming was compared with other activities such as
reading and listening to drumming sessions. Group drumming showed an
increase in NK cell (white blood cell which reject virally infected cells) activity
which indicates enhance performance in immune functioning [98].
Compared to younger adults, group drumming counteracted age-related
declines in the immune functioning for older adults (>60 years). Significant
increase of lymphocytes (white blood cells) was observed in older people as
compared to younger adults [94].
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30. Immunity - (Other findings)
The salivary immunoglobulin (s-IgA), usually found in saliva and mucus, is a first
line of defence against bacterial and viral infections [103].
Increased salivary immunoglobulin s-IgA concentrations were also observed after
having participants listen to experimenter-chosen, relaxing music. Silence was
the only control, therefore, attentional engagement or mood arousal could have
influenced the experiments (Table 2).
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31. Immunity - (Recommendations)
The effects of group drumming involved many different activities in one, such as
music, humour and instructor guidance (attention).
In order to compare the effects of music alone, other similar activity that involves
same actions could be used to compare results -- such as storytelling and skit-
acting.
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33. Social Affiliation
▹ Social behaviours involving groups of people, such as music, dancing,
clapping, marching, play an important role in human health outcome [109].
▹ Two neuropeptides, oxytocin and vasopressin (social behaviour regulators)
are in charge of mediating social effects of music.
▹ Oxytocin can be a hormone, neuropeptide, and medication. Oxytocin is
typically produced in the hypothalamus region. It plays a key role in social
bonding and sexual reproduction.
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34. Social Affiliation - (Findings)
▹ Music is regarded as a system for emotional communication, which is
observed to increase oxytocin levels [110, 111].
▹ Oxytocin levels increased in these three different cases: maternal speech,
singing lessons, patients undergoing open-heart surgery and passively
listening to music [119, 57, 120].
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35. Social Affiliation - (Recommendations)
Different non-musical controls are needed for different social context (alone, in
groups, with a teacher, etc.), medium of expression (vocal or verbal activities),
types of intervention (active or passive), and mood.
Example of control condition 1: listening to audiobooks vs. passive music
listening.
Example of control condition 2: private singing lesson vs. lesson for public
speaking.
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36. Conclusions
▹ Some experiments were biased and lacked proper control conditions.
▹ Even though the aforementioned studies each present major limitations,
music is still seen as a promising experimental device since it is noninvasive,
have minimal side-effects, are inexpensive and are completely ‘natural’.
▹ Music for therapy is yet to be tested by licensed therapists. This presents an
opportunity to introduce experts into the experiments where a more
professional perspective could be introduced.
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