As the debilitating effects of stroke are becoming more cause for concern, therapists have been looking for an effective method through which stroke patients can be rehabilitated. Strokes occur as a result of an interruption of blood flow in the brain, leading to a sudden decrease of brain function. They can be classified into two main categories, hemorrhagic and ischemic . In an ischemic stroke, blood flow is halted or disrupted to certain brain areas due to numerous reasons, such as a clot or obstruction in the arteries. The lack of blood to these areas starves the neurons of oxygen, glucose, and other vital metabolites that are necessary in order for them to function. A hemorrhagic stroke is caused when a blood vessel (such as an aneurysm) bursts and causes blood to accumulate in the brain and cause intracranial pressure(click here for a video module). Depending on where the rupture occurs, a patient with hemorrhagic stroke can present with specific symptoms . Strokes that affect the left cerebral hemisphere can impact speech function and motor and sensory deficits for the right side of the body, while strokes in the right hemisphere can cause hemineglect (on the left side of the body) and depth perception. Strokes are not limited to the cerebral hemispheres, however, such that strokes in the cerebellum affect motor coordination and strokes in the brainstem affect basic functions .
|The darkened region on the left
shows the extent of the damage from an ischemic stroke
Due to the widespread damaging effects, rehabilitation is often an extensive, gruelling process for a stroke patient. Professionals from various disciplines often collaborate to help return a patient as much as possible to normal life. Stroke victims may undergo any or all of the three common types of therapy: physical therapy, in which certain exercises and procedures allow a patient to recover lost physical function ; occupational therapy, which allows patients to re-learn and develop the skills that are essential to maintain daily living and social interactions ; speech-language pathology therapy which re-trains patients that have lost communication and/or swallowing skills as a result of the stroke . Music was used informally while treating the veterans after the first and second World Wars; it has since then become an increasingly recognized form of therapy. While the “healing” properties of music have been discussed for centuries, it was only with the advent of brain imaging techniques that the scientific community began to take interest in this field . As more research is being conducted to explore the effectiveness of music therapy, a more diverse and proactive therapeutic program can be used to help rehabilitate stroke victims.
History of music therapy
Music as a form of therapeutic treatment in Canada can be traced to as early as 1849, as a few case studies describe the remarkable effects that music had on patients . Frank Herman, Norma Sharpe and Thérèse Pageau were three therapists who endeavoured to raise awareness of music therapy in Canada . In August of 1974, The Canadian Music Therapy Association was founded; its name was later changed to the Canadian Association for Music Therapy (CAMT) . Today, a number of music faculties offer a Bachelor of Music Therapy program, including Wilfrid Laurier  and Capilano University .
|Berklee's Music Therapy program|
|This is the first video of a three-part series that demonstrates music therapy in a clinical setting,
while providing a brief overview of the program at Berklee College of Music.
Why use music therapy?
Across cultures and throughout history, music has shown itself to be not only an enjoyable relaxing activity, but it also appears to stimulate many emotional and cognitive functions . As the technological age continues to encourage the creation of innovative devices (such as mp3 players and iPods), more people are able to gain access to music. The Internet has also become a medium through which music can be shared and stored faster than ever before. As people often come into contact with some form of music on a daily basis, the properties of music that allow it to evoke emotions, calm stress, and bring people together are being increasingly valued. From young teenagers who might use it to express their identity and beliefs to the older adults who just enjoy the musicality of certain pieces, music plays an essential role in the lives of all age groups.
While people often describe their subjective personal experiences while listening to music, researchers are often more interested in studying the physiological changes that accompany these emotions. These changes include heart and breathing rates, skin properties, and hormone fluctuations . Due to its ability to stimulate arousal, music can also temporarily have a positive impact on a person’s cognitive function, rational thinking, memory capacity, and the speed of processing sensory stimuli . Although some studies have produced contradictory results, researchers have shown that information can be better recalled when it has been integrated into the lyrics of a song than when it has just been memorized . Patients with aphasia have improved memory recall for words and can repeat words more smoothly while singing compared to regularly speaking . Music has been used to stimulate positive arousal, which may result in increased levels of dopamine in the brain; this is important because dopamine can be implicated in learning, memory and problem solving skills . Transient effects can also be observed after listening to music. Children with attention deficit hyperactivity disorder were shown to improve in their arithmetic skills after listening to music for a period of time . The same effect was shown on memory for patients with Alzheimer's disease .
Expansive neural networks
|The animation outlines a few of the regions that are involved in processing music|
With the development of brain imaging methods like functional Magnetic Resonance Imaging (fMRI) and Positron Emission Tomography (PET) scans, scientists were able to investigate the areas of the brains that are responsible for processing music. This was done mainly by studying patients with a brain lesion that affected their ability to perceive and process music (amusia). The scans showed that melodies and changes in pitch and tone qualities elicit responses in the auditory cortex and surrounding temporal lobe. The processing of these musical properties appears to be done predominantly in the right hemisphere . The temporal properties of music (such as tempo and rhythm), on the other hand, seem to stimulate activity in both hemispheres, including areas like the auditory cortex, and the temporal, parietal lobe, and frontal loves . While just listening to the rhythm and melody of a musical piece stimulates large portions of the cortex, processing the other components adds yet another layer of complexity. Harmonic attributes and chord structures elicit responses from the inferior frontal gyrus, the superior temporal gyrus, and the premotor cortex . Another network can be traced from the inferior and dorsolateral prefrontal cortex, through the cingulate cortex and into the parietal areas as a melody line is remembered; this is because it involves working memory and focused attention . Recognizing a familiar melody also appears to activate the circuitry in the insular cortex and superior temporal gyrus . Listening to music can elicit strong emotions, which is supported by the fact that the “emotional” content of music stimulates activity in the limbic system, the hippocampus, amygdala, and parts of the basal ganglia . The fact that listening to music triggers activity in such expansive neural networks is one reason why using music as a form of therapy is so effective. As music can have a positive impact on affect and emotion, music listening can be used to help combat episodes of depression and other psychiatric disorders that sometimes occur in post-stroke stages. Additionally, the implications of a stroke are often that many neurons die due to a lack of oxygen and important metabolites. As a result, the brain must learn to ‘re-wire’ itself in order to re-gain lost functions. The conclusions and findings from studies converge to implicate music as a reliable method to re-activate and establish neuronal pathways that link the various regions of the brain.
Models of music therapy for rehabilitation
Melodic Intonation Therapy
|Melodic Intonation Therapy|
|This video provides a detailed description of MIT along with an example|
Melodic Intonation Therapy (MIT), a model used in the rehabilitation of stroke victims, uses the melodic and rhythmic properties of music to teach patients with nonfluent aphasia to speak . Building on the premise that aphasic patients can produce words fluently while singing but not while speaking, the MIT uses humming or singing to exaggerate normal intonation that is present in speech production. The four-stage process begins with the therapist humming certain phrases, with the patient tapping out the rhythmic patterns with their hands or feet. In the second phase, the patient continues to tap out the beat, but also hums along with the therapist. The third stage develops the patient’s memory, as they must wait for a certain period of time before they can repeat the phrase. The fourth stage is meant to facilitate the transition from the singing style to normal speech production. This stage focuses on slowly removing the musical elements from the phrase such that the patient can speak normally . This form of therapy is important because it re-teaches the stroke patient to master the art of integrating intonation and rhythm into speech. The patient will often undergo an intensive program of 7.5 hours a week until the patient has successfully completed all the stages. It has been suggested that since MIT involves the Broca's area to produce lexical content and prosodic regions to produce intonation, this form of therapy may be exclusive in its ability to engage both hemispheres . Numerous factors might contribute to the successfulness of this form of therapy. Singing allows the patient to reduce the speed at which words are produced in comparison to speaking; this reduces a reliance on the left hemisphere. The “chunking” and lengthening of syllables might allow the patient to group syllables and intonation into manageable portions, while stimulating a greater response from the right hemisphere. The tapping of the hands and/or feet might also allow for the rhythmic entrainment of speech . Research that compares the MIT to rehearsed production of speech shows that MIT results in superior speech production; the effects are also shown to last longer .
Rhythmic Auditory Stimulation
|Rhythmic Auditory Stimulation|
|With the aid of music, patients are taught to
walk to a constant steady beat
Rhythmic Auditory Stimulation (RAS) makes use of the rhythmic qualities of music to train motor behaviour patterns, i.e., gait. The model entrains synchronicity between the patient’s motor movements and the stable metre (tempo) of music . The program can vary from a few weeks to several months. The model has been shown to have no side effects, and the fact that the patient chooses the music increases enjoyment of the rehabilitative therapy and enhances patient overal satisfaction with the program. The important aspect of this model is that it relies on the stability of rhythm to serve as a template to which the patient can couple walking movements. Studies that evaluated the effectiveness of the RAS model found that the progress that a patient made in terms of velocity, cadence and stride length were of a higher statistical significance than other “non-musical” methods of therapy .
Music listening as a leisure activity
Sarkamo & Soto (2012) are Finnish researchers that expanded on the beneficial effects of listening to music for stroke patients . What made this research innovative is that the authors investigated the effects of listening to music as a leisure activity after a stroke, compared to its predecessors, which only examined music in a controlled, clinical setting. Their first study targeted patients that had developed hemineglect on their left visual field as a result of a stroke in the parietal regions of their right hemisphere. The patients were assigned to conditions in which they either did not listen to music, listened to music that was given to them, or were able to listen to music of their own choice. Various scales of overall enjoyment and mood were given throughout the study; patients in the preferred music condition were found to have positive affect. The patients in the preferred music condition also improved in their ability to perceive stimuli in their left visual field compared to patients in the no music and unpreferred music conditions. In the second part of the study, the sample was comprised of patients that had suffered from an acute ischemic stroke. They were randomly assigned to a control group (no audio stimuli), a book condition, or a music condition. The patients in the audio conditions listened to audio books or preferred music selections on a daily basis and kept a record of what they listened to. At the end of the study, patients were given questionnaires that evaluated neuropsychological aspects, such as attention, cognitive function and affect. Patients in the music condition were found to show improvements in verbal memory and focused attention that were of higher statistical significance than those in the book or control condition. In addition, listening to music helped reduce depression and negative affect. This study suggests that even listening to music as a leisure activity can help improve cognitive function and reduce negative affect in stroke patients.