MUSIC, SOUND, AND THE HEALTHY BRAIN COURSE DESCRIPTION Whether you are listening to rock music in your car or listening to Mozart at home, music affects your brain. Engaging in musical activity (such as listening to or creating music) involves almost every region of our brain as well as our minds, our thoughts, and our spirit. The goal of this course is to describe the elements of and principles of sound; discuss how music engages the whole brain; identify the whole-body benefits of music; and examine the physiological and psychological effects of music. LEARNING OBJECTIVES 1. Describe the elements of music. 2. Describe the principles of sound. 3. Discuss how music engages the whole brain. 4. Explain the whole-body benefits of music. 5. Identify the physiological effects of music. 6. Identify the psychological effects of music.
INTRODUCTION Music as a healing modality is probably as old as the first sound made by a man or a woman. Early humans used sounds in sacred and ritualistic ways to promote fertility, accept death, grow crops, and commemorate events. Sound and music have been used in healing practices by virtually every culture throughout history (Cantello, 2004; Wigram, Pedersen, & Bonde, 2004). Pythagoras, a Greek philosopher, stated that music contributes to the natural harmony of the mind and the body (Moris & Linos, 2012). He taught his students to change their worries, fears, sorrows, and anger by singing and playing a musical instrument daily. Other Western philosophers, such as Plato, Aristotle, Augustine, and Nietzsche, considered the practical and theoretical role of music in relation to a person s health. Plato discussed the influence of music on the human mind (American Music Therapy Association [AMTA], 2014). Florence Nightingale understood the positive effects of harmonic and continuous sounds when she used wind instruments to help her patients heal (Moris & Linos, 2012). Profound scientific, medical, psychological, cognitive, physical, social, and spiritual connections are involved in the power of sound and music. Healing with music combines musical experiences with the inherent universal forms in music to heal the body, mind, and spirit. Like a tuning fork for the brain, music can stimulate specific regions to soothe emotions, boost the capacity for learning, and unlock creative genius (AMTA, 2014; Borysenko, 2001). Today, more people listen to music than ever before in the history of the world, and there are more avenues for experiencing music than anyone could have predicted years ago. Scientists can determine which neurons in the brain are firing when music is playing. By using functional magnetic resonance images (MRIs), scientists can study
how specific areas of the brain are activated while the individual listens to music. The field of music cognition (the study of music as a product of the human mind) existed before MRIs, but there has been significant growth in this field of research since the invention and utilization of MRIs. Music therapy, music psychology, and psychoacoustics (the study of the perception of sound, including how we listen, our psychological responses to sound, and the physiological impact of music and sound on the human nervous system) are being used to integrate positive sound and music into people s daily lives. Music can have positive benefits on all aspects of life. Consider the following examples: Patients in a critical care unit on ventilators who used self-initiated, selfdirected music (PDM) experienced less anxiety and needed less sedation than those who did not receive PDM (Chlan, et al, 2013). Musical sound (when compared to noise) positively impacts the quantity of seed that germinate (Creath & Schwartz, 2004). While this remains a bit controversial (Stevenson, 2008), the hypothesis continues to be tested. Some farmers have found that playing calming music improves the milk yield of dairy cows and even reduces the stress of chickens in large farms (BBC News, 2001; Godoy, 2014). Music is used as an effective form of therapy for veterans recovering from lifechanging experiences and overcoming post-traumatic stress disorder (PTSD). The music enhances their problem-solving skills and social interactions, help veterans deal with memories of war (Couch, 2014; United States Department of Veterans Affairs, 2013). In an age when people increasingly turn to holistic methods of healing, music and sound healing have become powerful and nonthreatening modality that can be used successfully with individuals of all ages and at any stage of health. THE ELEMENTS OF MUSIC Before examining how music affects the brain it is important to define some common musical terms. Music is an art form that uses vocal or instrumental techniques to produce sound and affect the mental status of the listener (Moris & Linos, p. 719). The principal elements of music are the following (Bennet & Bennet, 2009; Campbell, 2011; Levitin, 2006): Pitch: This element is related to the actual frequency of a particular tone and to its relative position in the musical scale. For example, one might ask what note is that? It s a C (or D, or F, etc.). Perfect pitch, or absolute pitch, is the ability of a person to identify or re-create a given musical note without the benefit of a reference tone. Perfect pitch can be achieved by average children between three
and five years of age with appropriate music training. Structual brain changes occur along with the development of perfect pitch and continue as musical talent matures. Tone: The initial sound is the tone or utterance of the sound. Every note is produced by a specific rate of vibration and produces both physical and psychological effects that cannot be expressed in words. Rhythm: Called the heart of music, rhythm structures tone and sound, giving it definition, pattern, and boundary. Rhythm includes elements such as tempo (speed) and meter (the grouping of beats). This fundamental element directly affects both the body and the emotions. Harmony: This element is the relationship between tones and their rhythmic pattern and it is produced by the simultaneous sounding of tones that blend with each other to form chords (a harmonic set of three or more notes that are heard as if they are sounding simultaneously). Melody: This element is a linear succession of musical tones that the listener perceives as a single entity. Melodies are produced by the combination of rhythms, tones, and accented notes or passages. Timbre: Musical instruments and the human voice give sound a certain quality that is difficult to define in words but evokes emotional responses. Timbre is what makes a particular musical sound different from another, even when they have the same pitch and loudness. THE PRINCIPLES OF SOUND Understanding the principles of sound is key to appreciating its capacity to produce therapeutic psychophysiologic outcomes. Sound is best understood as being a vibration that propagates an audible mechanical wave of pressure and displacement, through a medium such as air or water (Goldman, 2002). Everything in the universe is in a state of vibration. Vibration is energy itself, moving through matter (Emoto, 2006). According to Leeds (2001), sound is vibratory energy (p.10). In addition to understanding vibration, it is important to understand three additional principles of sound: frequency, resonance, and entrainment.
Frequency Sound is produced when an object vibrates in a random or periodic, repeated motion (Guzzetta, 2005). The frequency at which an object vibrates is its resonant frequency. Everything has a resonant frequency, whether one can hear it or not. The human ear can hear sound when its frequency, or pitch, ranges from 20 to 20,000 hertz (Hz). However, sound is heard not only through the ears but through every cell in the body (Gaynor, 2002). It is perceived through skin and bone conduction as well as through the other senses, such as sight, smell, and touch, and these inputs allow us to perceive an even wider range of vibrations than by hearing alone (Guzzetta, 2005). Low-frequency sounds tend to be calm and grounding, while fast tempos energize individuals (Campbell, 2011). Resonance Resonance is the sound or vibration produced in one object that is caused by the sound or vibration produced by another object. It is the quality of sound that causes it to stay loud, clear, and deep for a long time. The healing properties of sound and the vibration of homeostasis are identical to the vibration known as the Schumann resonance a mathematical number of oscillations calculated at 7.8 Hz. This frequency is the same frequency detected in many sounds of nature, such as whale or dolphin songs and waterfalls. Entrainment The study of patterns or shapes evoked by sound is called cymatics. Matter assumes certain shapes or patterns based on the vibrations, or frequencies, of the sound to which it is exposed. For example, a snowflake may take on a particular shape because it responds to sounds in nature. The human body is also a system of vibrating atomic particles acting as a vibratory transformer that gives off and takes in sound from the environment. Music can act as an environmental pacemaker by speeding up or slowing down heart rates, brainwaves, and respirations. The result is a gradual entrainment (or synchronization) of the body s vibrations with those of the music, along with a corresponding change in an individual s psychophysiologic state (Guzzetta, 2005).
Coined by Christian Huygens, the term entrainment refers to the phenomenon that occurs when two elements become synchronized and vibrate at the same sound frequency. In physics, this phenomenon is referred to as the law of conservation of energy. Entrainment involves the process of modifying brainwaves, respirations, movements, emotions, or thoughts by matching the rhythm of an external stimulus, such as music, to the mind and body. For example, slow music entrains the pulse to beat at a slower rate (causing a calming effect), while chaotic sounds entrain the pulse (and emotions) to a higher state of rate and tension (Campbell, 2011). Entrainment with relaxing music also decreases an individual s respiratory rate, metabolic rate, oxygen consumption, pain levels, and blood pressure while increasing their cognitive ability (Freeman, 2004; Huang & Charyton, 2008). Seaward (2011) defines entrainment as the mutual phase-locking oscillations of like frequencies in the same environment. In other words, the more powerful rhythmic vibration of one object changes the less powerful rhythmic vibration of another object to synchronize its rhythm with the first object. An example in nature is the synchronous menstrual cycles of women who live or work together. Another example is the ancient shamans use of the drumbeat to evoke entraining vibrations for healing interventions (Seaward, 2011). When used as a relaxation therapy, music can have a rhythm that duplicates the normal pulse beat of humans. The music can be nonsyncopated, lyric free, and used to harmonize with the body s rhythms or bring the body s own rhythms back into balance. Entrainment has been shown to be effective in critical care and in neonatal intensive care. One of the most effective methods for pain reduction is entrainment music, which moves a person toward a positive or pleasant mood state (Freeman, 2004). Goldman (2002) notes the principles of using resonance and entrainment are the fundamental concepts behind the use of sound to heal and transform. They are found in every practice that uses sound, regardless of the tradition, belief system, or culture (p. 15). MUSIC ENGAGES THE BRAIN The brain is divided into two hemispheres, referred to as the right and left hemispheres. It was previously believed that the right hemisphere was engaged exclusively when music was played or listened to, but research now shows that both sides of the brain are used during musical experiences. Music engages the whole brain (Cromie, 2002). For example, as sound enters the ears it travels up the auditory nerve to the auditory cortex in the temporal lobes. The temporal lobe in the nondominant hemisphere (generally the right hemisphere) hears pitch, melody, harmony, and beat and (recognizing long-term patterns) puts this together as a whole experience (Bennet, 2009).
The temporal lobe in the dominant hemisphere (generally the left hemisphere) is better at analyzing the incoming sound and hearing the short-term signatures of music, that is, lyrics and changes in rhythm (pacing), frequency, intensity, and harmonies. The frontal lobe associates sounds and music with thoughts and thus stimulates emotions (in the limbic system) and feelings from past experiences (from memory scattered throughout the brain). The cerebellum becomes involved in measuring the beats (spatial aspects) of the music (Bennet & Bennet, 2009). The superior temporal gyrus (in the temporal lobe) is resposnible for processing sounds and is also intimately involved with the experience of music. The types of music a person listens to over a lifetime impact how the superior temporal gyrus is formed (Landau, 2013). WHOLE-BODY BENEFITS OF MUSIC THERAPY According to the American Music Therapy Association (2014), music therapy is the clinical and evidence-based use of musical interventions to accomplish individualized goals within a therapeutic relationship by a credentialed professional who has completed an approved music therapy program. Music is a moral law. It gives the soul to the universe, wings to the mind, flight to the imagination, and charm and gaity to life and to everything. Plato Music is beneficial socially, cognitively, physically, emotionally, and developmentally. Due to these benefits, music therapy is used in hospitals, nursing homes, and psychiatric facilities (Bradt, Dileo, Drocke, & Magill, 2011; Finnerty, 2011).What is
interesting, though, is why it is beneficial. When used properly, music can be an incredibly powerful therapeutic tool producing a profound impact on the brain, the body, and the spirit (AMTH, 2014). Music is a core component of being human. The human brain is primed from birth to respond to, and process, sounds and music. Research has shown that day-old infants are able to detect differences in rhythmic patterns. Mothers across cultures and throughout time have used lullabies and rhythmic rocking to calm crying babies. From an evolutionary standpoint, music precedes language. The human brain is wired to respond to sounds and music (Cromie, 2002). Music entrains us to rhythms. Have you ever walked down the street humming a song, and noticed that you are walking to the beat? This is entrainment. When musical input enters the central nervous system via the auditory nerve, most of the input is processed in the brain. However, some of the input is directed to motor nerves in the spinal cord. This allows the muscles to move to the rhythm without having to think about it. This impacts how we dance to music, tap our foot to a rhythm, and walk in time to a beat. Music creates a physiologic response in the body. Many individuals find their breathing increases, their heart-rate increases, or they feel a shiver down their spine when they listen to certain sounds or a meaningful piece of music. This is an example of the body responding physiologically to the sound or music. Music taps into the emotions. Have you ever listened to a piece of music and smiled? Or felt sad? Because music is transmitted to the temporal lobe of the brain and then the limbic system, music taps into our emotions and past experiences. Music also imitates the tonal characteristics of emotions relayed through voice, and this taps into our innate communicative abilities, stirring the senses through different instruments, modes, and melodies.
Music helps improve attention skills. From an early age, music can hold our attention. This allows music therapists to focus on attention and impulse control goals, both essential skills for effective functioning in the modern world. Music uses shared neural circuits as speech. Listening to music or singing music with lyrics uses neural circuits that are the same as those used in language expression and speech. Music enhances learning. Many individuals learned their ABCs through a song. The inherent structure and emotional pull of music makes it an easy tool for teaching concepts, ideas, and information. Music is an effective mnemonic device, not only making information easy to learn, but easy to later recall. Music taps into our memories. Have you ever been driving, heard a song on the radio, then immediately been transported to a specific place, a specific time in your life, or a particular person? Music is second only to smell for it s ability to stimulate memories in a very powerful, emotional way. Music is a social experience. Our ancestors bonded and passed on their stories and knowledge through song, stories, and dance. Many of our current music experiences are shared with a group, whether it is playing in a band, listening to jazz at a restaurant, or singing in a church choir. Music is predictable, structured, and organized. Music often has a predictable steady beat, organized phrases, and a structured form. Most songs we know are often organized with a verse-chorus structure that makes them enjoyable to listen to over and over again. Even sound waves that make up a single tone or an entire chord are organized in mathematical ratios and the brain responds positively to this predictability and structure. Music is safe and motivating. Most people really enjoy listening to music. While this is not the most important reason for the effectiveness music therapy, it is the icing on the cake. PHYSIOLOGICAL BENEFITS OF MUSIC Listening to music regularly (and replaying tunes in our brains) helps neurons stay active and keeps synapse connections intact. Listening to music appears to facilitate learning, and participating more fully in creating music appears to provide additional cerebral advantages. For example, some types of music support hemispheric synchronization and the opportunity to achieve brain coherence (the orderly and harmonious connectedness between the two hemispheres of the brain). These two processes can significantly improve learning. While listening to music feels good, can it translate into real physiological benefits? (Bennet & Bennet, 2009; Levitin, 2007). It appears that musical experiences have real health benefits. For example, researchers studied patients who were about to undergo surgery. Prior to surgery, participants were
randomly assigned to either listen to music or take antianxiety medications. Scientists tracked each patient's ratings of their own anxiety, as well as the levels of the stress hormone, cortisol, in their blood. The results concluded that the patients who listened to music had less anxiety and lower cortisol levels than people who took the anti-anxiety medications. While more research needs to be done to replicate the results, the results of this research indicate a powerful therapeutic use for music (Levitin, 2007). Listening to music during a surgical procedure has been shown to reduce cortisol levels and reduce the need for excessive anesthetic medications (Koelsch, et al, 2011; Moris & Linos, 2012; Tabrizi, et al, 2012). Interestingly, for the staff, music is considered distracting but for surgeons, music can increase the speed and accuracy of task performance (Moris & Linos, 2012). Other physiological benefits from sound and/or musical experiences include the following (Cabrera & Lee, 2000; Cromie, 2002; Discover Alden, 2014; Koelsch, et al, 2011; Priesnitz, 2006; Tabrizi, et al, 2012; Wigram et al., 2004): Music masks unpleasant sounds and feelings. Many dental professionals understand the effects of music. They use it to mask the sound of the drill and dispel the uncomfortable feeling created by the harsh sounds and vibrations of the instruments. Music can slow and equalize brain waves. Beta waves occur during ordinary consciousness and vibrate from 14 to 20 Hz. Alpha waves occur during periods of heightened awareness and calm and they cycle from 8 to 13
Hz. Theta waves occur during periods of peak creativity, meditation, and sleep and they cycle from 4 to 7 Hz. Delta waves occur during deep sleep, deep meditation, and unconsciousness and they range from 0.5 to 3 Hz. Listening to certain types of music such as Baroque, New Age, and other ambient (with no dominant rhythm) music can shift an individual s consciousness from the beta toward the alpha range. Shamanic drumming can take the listener into the theta range. Music affects respiration. Breathing at a deep, slow rate is optimal for stress relief and contributes to a sense of calm. By listening to music with longer, slower rhythms, entrainment occurs. Breathing deepens and slows, creating a peaceful, relaxed sensation. Gregorian chant, New Age, and ambient music can create this effect. Music affects the heartbeat, pulse rate, and blood pressure. Musical variables such as frequency, tempo, and volume tend to speed up or slow down heart rate. The faster the music, the faster the heart rate; the slower the music, the slower the heart rate. A slower heartbeat calms the mind, creates less physical tension and stress, and helps the body heal itself. Blood pressure can be lowered by listening to music with a frequency of 44 55 Hz. Music reduces muscle tension and improves body movement and coordination. Through the autonomic nervous system, the auditory nerve connects the inner ear to the frontal lobe of the brain, which, in turn, is connected to every muscle in the body. Thus, muscular response, strength, flexibility, and tone are influenced by sound, vibration, and music. For example, music is used during yoga sessions to help individuals relax. It is also used in numerous health care settings, such as post-operative recovery units and rehabilitation clinics, to help individuals relax and retrain their muscles after surgery, accidents, or illnesses. Music affects body temperature. Because sound and music affect all muscles of the body (both voluntary and involuntary), as well as blood circulation, pulse rate, respiratory rate, and sweating, it can influence our body temperature. Loud music with a strong beat can raise body temperature by a few degrees; soft music with a weak beat can lower it. Music can increase endorphin levels and reduce pain. When sounds and music evoke positive emotions, endorphins are released. Endorphins are the body s natural analgesics and they produce a feeling in the body similar to morphine. Endorphins can lessen pain and induce a feeling of euphoria. Music can stimulate the release of endorphins, which can then decrease the need for pain medication, provide a distraction from pain, and relieve anxiety. Music can regulate stress-related hormones. Listening to relaxing, ambient music may reduce the level of stress hormones in the blood,
contributing to a sense of relaxation and calm, and in some cases reducing or eliminating the need for many types of medication. Music and sound can boost immune function. Insufficient oxygen in the blood may be a major cause of immune deficiency and degenerative disease. Listening to certain types of music as well as engaging in singing, chanting, and other vocal forms relaxes muscles and improves respiratory effort, resulting in better oxygenation of the cells. Music has the capacity to reach hidden areas of the brain. While no one has discovered a music center in the brain, there are unique circuits in the brain that respond specifically to music and they are different from the circuits in the brain that address speech and memory. This is why people with an impaired ability to speak or carry on a conversation due to a condition such as Alzheimer s disease, stroke or Parkinson s disease may still be able to sing. Music serves as a storehouse for memories. Pictures, thoughts and vivid recollections can all be encoded in the mind when an individual listens to music. Music helps people with memory loss access these memories, and also become more aware of the present, their surroundings and other people. Depending on the severity of the injury, even people who have some form of brain injury may regain partial or full access to memories by listening to music. Music can improve hearing and speech. Listening to music can enhance hearing by improving our ability to perceive speech in a noisy environment a common issue when age-related hearing impairment occurs. Music can decrease blood glucose levels. When stress levels are reduced through the use of sound and music, blood glucose levels also decline. High levels of blood glucose are associated with an increased risk for diabetes, decreased wound healing, and increased risk for several chronic diseases. Music may reduce the risk of these issues. Music encourages us to exercise and be more active. With the addition of music, movements become a pleasure rather than a chore. Music can improve sleep quality. Studies show that individuals who have sleep problems often experience improvement after listening to soft music at bedtime. This may be due to a decrease in stress hormones, an increase in muscular relaxation, or an increase in oxygen to the brain. Music can reduce the effects of chemotherapy. Sound healing is effective in controlling nausea and pain associated with chemotherapy (Schweitzer, Gilpin, & Frampton, 2004),
Music is useful in relieving stress in every age and in virtually every culture (Lichtman, 2006). Campbell (2011) notes, It s amazing that in just a few minutes, music can trigger responses in your heartbeat, emotions, and attentiveness. Almost instantly, you can be activated, awakened, and feel like dancing (p. xix). PSYCHOLOGICAL BENEFITS TO MUSIC Music evokes a wide variety of strong emotions (joy, amusement, amazement, feeling of vitalization, consolations, spiritualty, calmness, fear, anger, sadness, disgust, etc). People can become angry when they listen to music that they utterly dislike. However, most music evokes happiness more often than disgust (Koelsch, 2012). Music can improve emotional states as well as uplift the spirit. Music can produce many psychological responses including the following: It can reduce anxiety and fear, as well as create relaxing, soothing sensations (Campbell, 2011; Ingersoll, 2013; Koelsch, 2012; Lippin & Micozzi, 2011; Seaward 2011). Soothing music may produce a hypometabolic response, similar to a relaxation response, in which autonomic, immune, endocrine, and neuropeptide systems are altered (Koelsch, 2012). Music decreases preoperative anxiety in infants, and reduces visitor stress in hospital waiting rooms (Campbell, 2011; Schweitzer, Gilpin, & Frampton, 2004). Music therapy is used to treat individuals with mild traumatic brain injuries, post-traumatic stress disorder, depression, attention deficit hyperactivity disorder (ADHD), and other mental health issues (Campbell, 2011). Music therapy, incorporating the safety and predicability of certain types of music, is helpful for clients with severe psychotic disturbances because their world is often chaotic and disconnected from reality. When used appropriately, music therapy appeared may help the client achieve a more normal self-identity, experience greater personal freedom, create clearer personal boundaries, and achieve a greater degree of autonomy (Wigram et al., 2004).
SUMMARY Throughout history, people have played and enjoyed music. Listening to music and creating music provides an array of psychological and physiological benefits to the brain. As more research is conducted on the impact of music and the brain, there are many therapeutic possibilities for individuals with all types of acute and chronic health challenges. Listening to and creating music appears to have many advantages including the power to heal the body, mind, and spirit.
REFERENCES American Music Therapy Association. (2014). What is music therapy? Retrieved July 17, 2014 from http://www.musictherapy.org/about/musictherapy BBC News. (2001). Sweet music for milk. Retrieved September 4, 2014 from http://news.bbc.co.uk/2/hi/science/nature/1408434.stm Bennet, A. & Bennet, D. (2009). The human knowledge system: Music and brain coherence. Retrieved July 18, 2014 from http://www.monroeinstitute.org/research/cat/music1/the-human-knowledge-systemmusic-and-brain-coherence Bradt, J., Dileo, C., Drocke, D., & Magill, L. (2011). Music interventions for improving psychological and physical outcomes in cancer patients. Cochrane Database of Systematic Reviews, 10(8),1-3. Cabrera, I. N., & Lee, M. H. M. (2000, April). Reducing noise pollution in the hospital setting by establishing a department of sound: A survey of recent research on the effects of noise and music in health care. Preventive Medicine, 30(4), 339 345. Campbell, D. (2011). Healing at the speed of sound. London, England: Hudson Street Press. Cantello, M. (2004). Communing with music: Practicing the art of conscious listening. Camarillo, CA: DeVorss Chlan, L. L., Weinert, C. R., Heiderscheit, A., Tracy, M. F., Skaar, D. J., Guttormson, J. L., & Savik, K. (2013). Effects of patient-directed music intervention on anxiety and sedative exposure in critically ill patients receiving mechanical ventilatory support: A randomized clinical trial. Journal of the American Medical Association, 309(22), 2335-2344. Couch, R. (2014). Veterans find family, healing in festival and electronic music culture. Retrieved September 4, 2014 from http://www.huffingtonpost.com/2014/08/22/electricforces-project_n_5697775.html Creath, K., & Schwartz, G. E. (2004). Measuring effects of music, noise, and healing energy using a seed germination bioassay. The Journal of Alternative and Complementary Medicine, 10(1), 113-122. Cromie, W. J. (2002). Music on the brain: Researchers explore the biology of music. Retrieved September 3, 2014 from http://news.harvard.edu/gazette/2001/03.22/04- music.html
Crowe, B. J., & Scovel, M. (1996) Special feature An overview of sound healing practices: Implications for the profession of music therapy. Music Therapy Perspectives, 14(1), 21 29. Discover Alden. (2014). How music supports health aging Retrieved August 2, 2014 from http://www.thealdennetwork.com/music-supports-healthy-aging/ Finnerty, R. (2011). Music therapy: A viable intervention for pain control. Canadian Nursing Home, 22(1), 5-9. Godoy, M. (2014). Moo-d music: Do cows really prefer slow jams? Retrieved September 4, 2014 from http://www.npr.org/blogs/thesalt/2014/03/06/285314648/secret-life-ofcows-part-deux-milking-mood-music Huang, T. L., & Charyton, C. (2008). A comprehensive review of the psychological effects of brainwave entrainment. Alternative Therapies in Health and Medicine, 14(5), 38-50. Ingersoll, S. S. & Schaper, A. (2013). Music: A caring, healing modality. In B. M. Dossey, & L. Keegan, Holistic nursing: A handbook for practice (6th ed., pp. 397 415). Sudbury, MA: Jones and Bartlett Learning. Koelsch, S. (2012). Brain & music. Hoboken, NJ: Wiley-Blackwell. Koelsch, S., Fuermetz, J., Sack, U., Bauer, K., Hohenadel, M., Wiegel, M., Kaisers, U. X., & Heinke, W. (2011). Effects of music listening on cortisol levels and propofol consumption during spinal anesthesia. Frontiers in Psychology, 2, 58. Landau, E. (2013). This is your brain on music. Retrieved September 4, 2014 from http://www.cnn.com/2013/04/15/health/brain-music-research/ Levitin, D. J. (2007). This is your brain on music. New York, NY: Plume Printing. Lippin, R. A., & Micozzi, M. S. (2011). The arts in medicine. In M. S. Micozzi, Fundamentals of complementary and integrative medicine (4th ed., pp. 163 176). St. Louis, MO: Saunders Elsevier. Moris, D. N., & Linos, D. (2012). Music meets surgery: Two sides to the art of healing. Surgical Endoscopy, 27(3), 719-723. Priesnitz, W. (2006, May June). Music is medicine for body and soul. Natural Life, 10 11. Schweitzer, M., Gilpin, L., & Frampton, S. (2004). Healing spaces: Elements of environmental design that make an impact on health. Journal of Alternative and Complementary Medicine, 10(Suppl. 1), S71 S83.
Seaward, B. L. (2011). Managing stress: Principles and strategies for health and wellbeing (7th ed.). Sudbury, MA: Jones and Bartlett. Stevenson, A. (2008). Probing question: Does talking to plants help them grow? Retrieved September 4, 2014 from http://news.psu.edu/story/141343/2008/08/25/research/probing-question-does-talkingplants-help-them-grow Tabrizi, E. M., Sahraei, H., Rad, S. M., Hajizadeh, E., & Lak, M. (2012). The effect of music on the level of cortisol, blood glucose and physiological variables in patients undergoing spinal anesthesia. EXCLI Journal, 11, 556-565. United States Department of Veterans Affairs. (2013). Music therapy: Helps soothe PTSD symptoms. Retrieved September 4, 2014 from http://www.visn9.va.gov/visn9/news/vcl/fall2013/music_therapy.asp Wigram, T., Pedersen, I. N., & Bonde, L. O. (2004). A comprehensive guide to music therapy: Theory, clinical practice, research, and training. Philadelphia: Jessica Kingsley.