Resources & references

This is an Editorial on the following Research Topic: The Clinical Neuroscience of Music: Evidence Based Approaches and Neurologic Music Therapy.

Driven by new insights from research in music and brain function, a new understanding of the capabilities of music as a complex auditory language in therapy and rehabilitation has emerged over the past 25 years. Research has shown that music engages complex perceptual, cognitive, affective, speech/language, and motor control processes in the human brain. Furthermore, translational research approaches have shown that brain processes in music perception, music cognition, and music production can engage and shape non-musical perceptual, cognitive, language, and motor functions to effectively retrain the injured brain in neurorehabilitation and neurodevelopment. Music has become a language of science again as well as a new language to change the brain.

Parkinson’s disease (PD) is characterized primarily by a dysfunctional basal ganglia (BG) system, producing
motor and non-motor symptoms. A significant number of studies have demonstrated that rhythmic auditory
stimulation can improve gait and other motor behaviors in PD that are not well managed by the conventional
therapy. As music, being highly complex stimulus, can modulate brain activity/function in distributed areas of
brain, the therapeutic properties of music potentially extend to alleviate non-motor symptoms of PD. Despite the
clinical, behavioral evidence and promises of rhythm and music based interventions, the neural substrates underlying the effectiveness are poorly understood. The goal of this review is to appraise the current state of
knowledge in order to direct further neuroimaging studies that help to determine the therapeutic effects of
rhythm and music based interventions for motor and non-motor symptoms of PD.

Entrainment is defined by a temporal locking process in which one system’s motion or signal frequency entrains the frequency of another system. This process is a universal phenomenon that can be observed in physical (e.g., pendulum clocks) and biological systems (e.g. fire flies). However, entrainment can also be observed between human sensory and motor systems. The function of rhythmic entrainment in rehabilitative training and learning was established for the first time by Thaut and colleagues in several research studies in the early 1990s. It was shown that the inherent periodicity of auditory rhythmic patterns could entrain movement patterns in patients with movement disorders (see for a review: Thaut et al, 1999). Physiological, kinematic and behavioral movement analysis showed very quickly that entrainment cues not only changed the timing of movement but also improved spatial and force parameters. Mathematical models have shown that anticipatory rhythmic templates as critical time constraints can result in the complete specification of the dynamics of a movement over the entire movement cycle, thereby optimizing motor planning and execution. Furthermore, temporal rhythmic entrainment has been successfully extended into applications in cognitive rehabilitation and speech and language rehabilitation, and thus become one of the major neurological mechanisms linking music and rhythm to brain rehabilitation. These findings provided a scientific basis for the development of Neurologic Music Therapy.

Modern music therapy, starting around the middle of the twentieth century was primarily conceived to promote emotional well-being and to facilitate social group association and integration. Therefore, it was rooted mostly in social science concepts. More recently, music as therapy began to move decidedly toward perspectives of neuroscience. This has been facilitated by the advent of neuroimaging techniques that help uncover the therapeutic mechanisms for non-musical goals in the brain processes underlying music perception, cognition, and production. In this paper, we focus on executive function (EF) and attentional processes (AP) that are central for cognitive rehabilitation efforts. To this end, we summarize existing behavioral as well as neuroimaging and neurophysiological studies in musicians, non-musicians, and clinical populations. 

Music-based interventions (MBIs) are emerging as a new potential treatment strategy for neurologic and psychiatric patient populations, as they are safe, economic, and can be creatively tailored to meet specific functional goals. MBIs are typically selected and delivered by a credentialed music therapist based on empirically supported models and can involve active (improvisation, singing, clapping, or dancing) and/or receptive (purposeful music listening to identify emotional content emerging from music) techniques. Mechanistically, MBIs appear to engage both cortical and subcortical areas governing attention, working memory, planning, and flexibility and can modulate these areas over time.

The focus of this paper is threefold: 1) an overview of empirical studies using natural movement sounds and movement sonification in sports; 2) a review of recent clinical and applied studies using rhythmic auditory information and sonification in rehabilitation, addressing in particular studies on Parkinson’s disease and stroke; 3) Summary of current evidence regarding the cognitive mechanisms and neural correlates underlying the processing of auditory information during movement execution and its mental representation.