Music therapy for non-fluent aphasia is a method for treating patients who have lost the ability to speak after a stroke or accident. Non-fluent aphasia, also called expressive aphasia, is a neurological disorder that deprives patients of the ability to express language. It is usually caused by stroke or lesions in Broca’s area, which is a language-dominant area responsible for speech production in the left hemisphere. However, lesions in Broca’s area only affects patients’ speech ability, while their ability to sing remains unaffected. Since several studies have shown that right hemispheric regions are more active during singing, music therapy involving melodic elements is deemed to be a potential treatment for non-fluent aphasia, as singing might activate patients’ right hemisphere to compensate with their lesioned left hemisphere. Aside from singing, many other music therapy techniques have also been attempted and the effectiveness of some techniques is shown. Although there are many possible explanations for the mechanism of music therapy, the underlying mechanism remains unclear, as some studies indicate contradictory results.
Techniques
Therapeutic singing
A common method of therapeutic singing is guiding patients to sing familiar songs. Patients are led to sing along the song with therapists, who might adjust the tempo, volume, and pitch according to each individual patient to optimise the therapy process. The lyrics that patients can most easily produce are repeated several times. The employment of singing in the treatment of aphasia is not a novel therapy technique, as in the past therapists already noticed that patients who had difficulty speaking were still able to sing.
Vocal intonation
Vocal Intonation is introduced to make aphasic patients intentionally exaggerate the intonation of daily phrases. The most well-known application of vocal intonation in music therapy is Melodic Intonation Therapy (MIT). When receiving MIT, patients intone phrases with 2–3 syllables on only two pitches, which are determined by the natural prosody of phrases. Stressed syllables are intoned on a higher pitch, while unstressed syllables are intoned on a lower pitch. However, various intonation in daily conversational phrases may be used, so patients can practice communicating different meanings through different intonation. In addition, body cues, such as head or hand movement, may be used to help patients perceive different pitch in vocal intonation.
Dynamically cued singing
Dynamically cued singing was also used by therapists a long time ago. Therapists will guide patients to finish an incomplete sentence by singing the name of a designated object, such as “hand” if a therapist points to a patient’s hand. Additionally, dynamically cued singing can be employed together with singing familiar songs. Therapists may pause at the end of each phrase of a song to let patients finish the phrase by singing. This technique creates a strong interpersonal interaction that not only enhances patients’ motivation to participate, but also offers a circumstance similar to real conversation that benefits patients’ skills outside of music.
Breathing into syllable sound
At beginning, therapists will ask patients to focus on breathing single-syllable sounds only. The effect of this technique is enhanced if therapists can guide patients to produce the sounds with their natural breathing patterns that help them relax, such as yawning, signing, or cleaning voices. Later on, patients will be encouraged to develop the breathing sounds into pitched sounds. Hand movement may be used to help patients synchronize syllable sounds with exhaling. Usually, the single-syllable sounds begin from vowels to consonants. However, it is also suggested that the procedure should be from bilabial sounds (i.e. /m/, /b/), tongue-tip sounds (i.e. /n/, /d/), to tongue-base sounds (i.e. /g/, /k/).
Musically assisted speech
Patients will produce conversational phrases with melodies that the patients are familiar with to practice the real conversation that the patients may need in their daily life. This technique leads to more successful outcomes if original lyrics of the melodies are presented before the melodies are associated with conversational phrases. The method was also conducted by therapists more than 40 years ago and indicated to be effective. Keith and Aronson had recorded that their stroke patient rehabilitated from aphasia by singing simple conversational phrases to communicate with people.