Article Type : Short commentary
Authors : Nishikiori Y, Bando H and Yoshioka A
Keywords : Auditory-motor synchronization (AMS); Mirror neurons; Auditory-Motor Entrainment; Motor economy; Vibration coupling
Authors have continued the activity of Integrative Medicine Japan (IMJ) for managing art therapy, music therapy and physical therapy. When people listen to music, certain phenomenon would be observed where the sense of rhythm and physical movements are synchronized to the same rhythmic stimuli as auditory-motor synchronization (AMS). For these mechanism, mirror neurons in the brain are deeply involved, and causes movements and reactions in sync with the rhythm. Synchronizing the body movement is also called as Auditory-Motor Entrainment that showed research development in biology and psychology. Physical movements improve "motor economy" by matching them to a certain tempo
Music contributes much not only for
art and culture, but also greatly for mental and physical health, which is
deeply related to psychosomatic medicine [1]. The authors have been involved in
the management of Integrative Medicine Japan (IMJ), Shikoku Island division
[2]. Furthermore, we have continued various research for Integrative Medicine
(IM) involving art therapy, music therapy and physical therapy [3]. Among them,
the power of music has been known from various points of view. Listening to
music activates the mechanism of rhythm and synchronization with physical
movements [4]. Especially, vibration coupling has been a fundamental mechanism
of communication, and it has been suggested that cardiac rhythm plays a causal
role in regulating neural vibrations. Various activities of dance, music,
hiking and yoga were investigated in the light of empirical aspects. From
generalized perspectives, they include plural bio-psycho-social studies, and
several research of relationship among music, rhythm sensation, and related
physical movements [5]).
When people listen to music,
certain phenomenon would be observed where the sense of rhythm and physical
movements are synchronized to the same rhythmic stimuli as Auditory-Motor
Synchronization (AMS) [6]. This mechanism is closely related to the brain,
nervous system, and motor system. Lots of interdisciplinary studies are found
from the perspectives of neuroscience, psychology, and musicology. Several
impressive topics will be introduced in this article.
Rhythm and the brain can be
synchronized. For human being, hearing and movement usually interact. The
rhythm of music activates not only the auditory cortex (the area of the brain
that processes sound) but also areas involved in movement (the motor cortex and
cerebellum) [7]. This allows the beat of the music to affect human motor
system, making it easier for the body to move in time with the rhythm.
Furthermore, brainwaves also have rhythm. The constant rhythm of music
stimulates certain frequency bands of the brainwaves, such as alpha and gamma
waves. These changes in brainwaves increase attention and concentration while
also promoting synchronization with physical movements.
Rhythm is an essential element of
music. The rhythm that people perceive has the power to affect their emotions
and evoke certain feelings. For example, fast-tempo music increases energy of
the person, while slow music promotes relaxation. In this way, the emotional
reactions that arise in people's minds unconsciously affect their physical
movements. Simultaneously, they tend to have their movements in synchronization
with the rhythm. The "mirror neurons" in the brain are deeply
involved in the reason why people can respond to rhythm and movement [8]. These
neurons have the ability to enter a state of readiness to imitate the actions
or sounds of others just by seeing or hearing them. In fact, the rhythm of
music stimulates this system, causing movements and reactions in sync with the
rhythm.
This sense of rhythm not only
influences emotional responses and the responsiveness of mirror neurons in the
cerebrum, but also has a close influence on physical movements. It brings the
smooth movements of the upper/lower limbs and trunk. In other words, physical
movements improve "motor economy" by matching them to a certain tempo
[9]. For example, if a person listens to music and move to the beat of the
music while walking or running, one can move more efficiently. Dance and rhythm
training are further continuous programming using this principle. In recent
years, music videos have become a popular form of video. In this way, music
plus dance can improve the sense of rhythm and strengthens the sense of unity
between the body and music. Continuing this practice promotes brain plasticity
or adaptability, creating a cycle that further strengthens the response to
music.
Some people can recognize the beat
of music and synchronize their body well, but it varies from person to person
[10]. The reason would be that each person has different cultural background,
past experiences, and other personal situations, which have deep influences.
There are many different regions and cultures on the earth. People who were
brought up in certain cultures are accustomed to a certain rhythm and beat
feeling. Furthermore, people who have been musically trained since childhood
tend to have a high sensitivity to rhythm. An example can be presented as a
four-beat rhythm music. Anyone can clap their hands, bend their knees, and lower
their center of gravity at the point of 1st and 3rd beat. However, it is rather
difficult to feel and dance for emphasizing the off-beat. In the case of
talented dancers and jazz players, they can easily perform body movements along
the off-beat rhythm. Such well-trained people can allow audiences and listeners
for feeling a subtle shift in rhythm, creating tension, excitement and elation.
Regarding these phenomena of
synchronizing the body movement, the specific term ‘entrainment’ has been used
as Auditory-Motor Entrainment [11]. The research of rhythmic entrainment has
been developed in biology and psychology. Among them, energy effect of walking
rhythms, synchronization with music or efficacy of music rehabilitation on
patients with stroke. Entrainment has been known as natural phenomena which
were translated into synchronization. They refer to the situations where
systems and objects have shared some common periodicity and started to move
together. They have observed in physical movements and biological rhythms, in
addition to the conditions where the human body and coefficients were
synchronized to the musical rhythm. Such phenomena have been investigated for
crucial academic topics in natural sciences, neuroscience, biology, psychology
and so on. In human cases, entrainment are usually observed in the music
experiences with various rhythms. Specially, hearing music and also body
movements are simultaneously synchronized together with influencing each other.
Such phenomena are regarded as the basis of rhythmic movement and dancing which
binds music and physical movements.
In summary, general information and
recent perspectives were described concerning auditory-motor synchronization
(AMS), coupling mechanism between sound rhythm and physical movement. When
adequate music is given, it is easier for human body to move in time with the
regular rhythm. It is expected that this article will become useful and
beneficial for future research.
Conflict of Interest
The authors declare no conflict of
interest.
Funding
There was no funding received for
this paper.