One of the most visually impactful ways that NMT is incorporated into healthcare is in movement. If you need proof of this just click here to see MedRhythms in action. Neurologic Music Therapists’ utilize three techniques to engage and encourage movement:

·       Patterned Sensory Enhancement (PSE)

·       Therapeutic Instrumental Music Performance (TIMP)

·       Rhythmic Auditory Stimulation (RAS)

What each of these techniques has in common is that the NMT is supplying an auditory input that creates a desired motor output. In many cases this can look quite magical, and it can be easy to fall into believing that the music is simply enchanting. However, we (the neuroscience community “we”) have a pretty good idea how this works, and it has nothing to do with David Blaine.

 

Entrainment. Specifically rhythmic entrainment; this is the main ingredient which makes these three techniques so successful.  According to Hoemberg’s chapter in the Handbook of Neurologic Music Therapy, rhythmic entrainment is “the mechanism… in which acoustical rhythms entrain neural responses in auditory and motor structures,” (pg. 10). This theory, in its most rudimentary form, says when music/rhythm is employed, the neurons in our auditory and motor cortices begin to work in synchrony to create a movement. If you find this difficult to imagine, think about what happens when your favorite song starts playing. If you dance, toe-tap or air-drum along, you do all of these things in time with your perception of the song’s tempo. This is not something you are doing thoughtfully; you are entraining to the tempo at a neural level and your body is creating a motor output to match.

 

PSE, TIMP and RAS all exploit a brain’s natural ability to entrain in order for the NMT to facilitate a specific movement. 

But how does entrainment happen? How do the auditory and motor cortices synch up like this? What is making them communicate in such a distinct way? Thaut and Abiru point out in their 2010 review that research dating back to the 60’s shows this is due to parts of the auditory system projecting into the motor system (Ermolaeva & Borgest, 1980; Paltsev & Elner, 1967; Rossignol & Melvill, 1976). In short, they are connected! According to Thaut and Abiru, more current research supports the presence of audio-motor pathways on the brainstem level (2010).  No wonder you can’t help but move to the beat, you are hardwired to do so!

Now that we’ve (the you and me “we”) covered what happens in a neurotypical brain and how a person’s movement can be affected by NMT, we should further explore what this means for neurodegenerative diseases, such as Parkinson’s. But alas, that seems as if it is a discussion for another blog post. Next time on the MedRhythms Blog…

--MedRhythms Blogger, Emily MacPherson

Ermolaeva, V. Y., & Borgest, A. N. (1980). Intercortical connections of the auditory areas with the motor area. Neuroscience and Behavioral Physiology, 10, 210-215.

Hoemberg, V. (2014). A neurologist’s view on Neurologic Music Therapy. In M. Thaut, & V. Hoemberg (Eds.), Handbook of Neurologic Music Therapy (pp. 7-11). Oxford, UK: Oxford University Press.

Paltsev, Y. I., & Elner, A. M. (1967).Change in functional state of segmental apparatus of spinal cord under influence of sound stimuli and its role in voluntary movement. Biophysics, 12, 1219-1226.

Rossignol, S., & Melvill, J.G. (1976). Audio-spinal influence in man studied by the H-reflex and its possible role on rhythmic movements synchronized to sound. Electroencephalography and Clinical Neurophysiology, 41, 83-92.

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