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The Role of Rhythm in Speech and Language Rehabilitation: The SEP Hypothesis.

Fujii S, Wan CY - Front Hum Neurosci (2014)

Bottom Line: For example, the mere presence of an underlying beat or pulse can result in spontaneous motor responses such as hand clapping, foot stepping, and rhythmic vocalizations.Here, we propose the "SEP" hypothesis, which postulates that (1) "sound envelope processing" and (2) "synchronization and entrainment to pulse" may help stimulate brain networks that underlie human communication.Ultimately, we hope that the SEP hypothesis will provide a useful framework for facilitating rhythm-based research in various patient populations.

View Article: PubMed Central - PubMed

Affiliation: Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Sunnybrook Research Institute , Toronto, ON , Canada.

ABSTRACT
For thousands of years, human beings have engaged in rhythmic activities such as drumming, dancing, and singing. Rhythm can be a powerful medium to stimulate communication and social interactions, due to the strong sensorimotor coupling. For example, the mere presence of an underlying beat or pulse can result in spontaneous motor responses such as hand clapping, foot stepping, and rhythmic vocalizations. Examining the relationship between rhythm and speech is fundamental not only to our understanding of the origins of human communication but also in the treatment of neurological disorders. In this paper, we explore whether rhythm has therapeutic potential for promoting recovery from speech and language dysfunctions. Although clinical studies are limited to date, existing experimental evidence demonstrates rich rhythmic organization in both music and language, as well as overlapping brain networks that are crucial in the design of rehabilitation approaches. Here, we propose the "SEP" hypothesis, which postulates that (1) "sound envelope processing" and (2) "synchronization and entrainment to pulse" may help stimulate brain networks that underlie human communication. Ultimately, we hope that the SEP hypothesis will provide a useful framework for facilitating rhythm-based research in various patient populations.

No MeSH data available.


Related in: MedlinePlus

A schematic model of changes in the basal ganglia-thalamo-cortical motor network with Parkinson’s disease and/or musical rhythm [modified from Galvan and Wichmann (2008)]. The left and right panels show the network without and with Parkinson’s disease, while the upper and lower panels show the network without and with musical rhythm, respectively. Blue arrows indicate inhibitory projections, while red arrows indicate excitatory projections. Changes in the thickness of the arrows indicate increase (thicker arrow) or decrease (thinner arrow) of the projections relative to the normal situation. The dashed lines around the SNc (substantia nigra pars compacta) indicate degeneration of dopaminergic neurons caused by Parkinson’s disease. GPe, external segment of globus pallidus; GPi, internal segment of globus pallidus; SNr, substantia nigra pars reticulata; STN, subthalamic nucleus; M1, primary motor cortex; PMC, premotor cortex; and SMA, supplementary motor area. Striatum has “direct” and “indirect” pathways to the basal ganglia (BG) output nuclei (GPi/SNr). Light blue, green, and yellow colors denote BG, thalamus, and cortex, respectively. D1 and D2 indicate subtypes of dopamine receptor. Parkinson’s disease induces hyper-activation of BG output nuclei (GPi/SNr) inhibiting activities of the thalamocortical projection neurons, which in turn decreases motor output, while musical rhythm induces hypo-activation BG output nuclei and thereby facilitates thalamo-cortical motor output.
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Figure 3: A schematic model of changes in the basal ganglia-thalamo-cortical motor network with Parkinson’s disease and/or musical rhythm [modified from Galvan and Wichmann (2008)]. The left and right panels show the network without and with Parkinson’s disease, while the upper and lower panels show the network without and with musical rhythm, respectively. Blue arrows indicate inhibitory projections, while red arrows indicate excitatory projections. Changes in the thickness of the arrows indicate increase (thicker arrow) or decrease (thinner arrow) of the projections relative to the normal situation. The dashed lines around the SNc (substantia nigra pars compacta) indicate degeneration of dopaminergic neurons caused by Parkinson’s disease. GPe, external segment of globus pallidus; GPi, internal segment of globus pallidus; SNr, substantia nigra pars reticulata; STN, subthalamic nucleus; M1, primary motor cortex; PMC, premotor cortex; and SMA, supplementary motor area. Striatum has “direct” and “indirect” pathways to the basal ganglia (BG) output nuclei (GPi/SNr). Light blue, green, and yellow colors denote BG, thalamus, and cortex, respectively. D1 and D2 indicate subtypes of dopamine receptor. Parkinson’s disease induces hyper-activation of BG output nuclei (GPi/SNr) inhibiting activities of the thalamocortical projection neurons, which in turn decreases motor output, while musical rhythm induces hypo-activation BG output nuclei and thereby facilitates thalamo-cortical motor output.

Mentions: Under the SEP hypothesis, patients with PD can benefit from synchronization and entrainment to a pulse in music to stimulate the subcortical–prefrontal network and the BG-thalamo-cortical network. As illustrated in Figure 3, the BG-thalamo-cortical network functions normally in healthy individuals (top left panel), whereas the network becomes abnormal in PD because of the degeneration of the dopamine-producing neurons in the substantia nigra pars compacta (SNc) (top right panel). The projections from the SNc to the striatum regulates the cortico-strital projections, and if the dopamigeneric neurons in the SNc are depleted, it leads to reduced inhibition in the “direct” pathway to the BG output nuclei (i.e., GPi: internal segment of globus pallidus and SNr: substantia nigra pars reticulata), which carries dopamine “D1” receptors. The degeneration of dopamigeneric neurons in the SNc also leads to increased inhibition in the “indirect” pathway to the BG output nuclei (GPi/SNr) via external segment of globus pallidus (GPe) and STN carrying dopamine “D2” receptors. Net action of the degeneration of dopanigeneric neurons in the SNc leads to the hyper-activation of the BG output nuclei (GPi/SNr) inhibiting activities of thalamocortical projection neurons, which in turn negatively affects motor output [for more detail, see DeLong (1990), Wichmann and DeLong (1996), Blandini et al. (2000), Galvan and Wichmann (2008), and Smith et al. (2012)].


The Role of Rhythm in Speech and Language Rehabilitation: The SEP Hypothesis.

Fujii S, Wan CY - Front Hum Neurosci (2014)

A schematic model of changes in the basal ganglia-thalamo-cortical motor network with Parkinson’s disease and/or musical rhythm [modified from Galvan and Wichmann (2008)]. The left and right panels show the network without and with Parkinson’s disease, while the upper and lower panels show the network without and with musical rhythm, respectively. Blue arrows indicate inhibitory projections, while red arrows indicate excitatory projections. Changes in the thickness of the arrows indicate increase (thicker arrow) or decrease (thinner arrow) of the projections relative to the normal situation. The dashed lines around the SNc (substantia nigra pars compacta) indicate degeneration of dopaminergic neurons caused by Parkinson’s disease. GPe, external segment of globus pallidus; GPi, internal segment of globus pallidus; SNr, substantia nigra pars reticulata; STN, subthalamic nucleus; M1, primary motor cortex; PMC, premotor cortex; and SMA, supplementary motor area. Striatum has “direct” and “indirect” pathways to the basal ganglia (BG) output nuclei (GPi/SNr). Light blue, green, and yellow colors denote BG, thalamus, and cortex, respectively. D1 and D2 indicate subtypes of dopamine receptor. Parkinson’s disease induces hyper-activation of BG output nuclei (GPi/SNr) inhibiting activities of the thalamocortical projection neurons, which in turn decreases motor output, while musical rhythm induces hypo-activation BG output nuclei and thereby facilitates thalamo-cortical motor output.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4195275&req=5

Figure 3: A schematic model of changes in the basal ganglia-thalamo-cortical motor network with Parkinson’s disease and/or musical rhythm [modified from Galvan and Wichmann (2008)]. The left and right panels show the network without and with Parkinson’s disease, while the upper and lower panels show the network without and with musical rhythm, respectively. Blue arrows indicate inhibitory projections, while red arrows indicate excitatory projections. Changes in the thickness of the arrows indicate increase (thicker arrow) or decrease (thinner arrow) of the projections relative to the normal situation. The dashed lines around the SNc (substantia nigra pars compacta) indicate degeneration of dopaminergic neurons caused by Parkinson’s disease. GPe, external segment of globus pallidus; GPi, internal segment of globus pallidus; SNr, substantia nigra pars reticulata; STN, subthalamic nucleus; M1, primary motor cortex; PMC, premotor cortex; and SMA, supplementary motor area. Striatum has “direct” and “indirect” pathways to the basal ganglia (BG) output nuclei (GPi/SNr). Light blue, green, and yellow colors denote BG, thalamus, and cortex, respectively. D1 and D2 indicate subtypes of dopamine receptor. Parkinson’s disease induces hyper-activation of BG output nuclei (GPi/SNr) inhibiting activities of the thalamocortical projection neurons, which in turn decreases motor output, while musical rhythm induces hypo-activation BG output nuclei and thereby facilitates thalamo-cortical motor output.
Mentions: Under the SEP hypothesis, patients with PD can benefit from synchronization and entrainment to a pulse in music to stimulate the subcortical–prefrontal network and the BG-thalamo-cortical network. As illustrated in Figure 3, the BG-thalamo-cortical network functions normally in healthy individuals (top left panel), whereas the network becomes abnormal in PD because of the degeneration of the dopamine-producing neurons in the substantia nigra pars compacta (SNc) (top right panel). The projections from the SNc to the striatum regulates the cortico-strital projections, and if the dopamigeneric neurons in the SNc are depleted, it leads to reduced inhibition in the “direct” pathway to the BG output nuclei (i.e., GPi: internal segment of globus pallidus and SNr: substantia nigra pars reticulata), which carries dopamine “D1” receptors. The degeneration of dopamigeneric neurons in the SNc also leads to increased inhibition in the “indirect” pathway to the BG output nuclei (GPi/SNr) via external segment of globus pallidus (GPe) and STN carrying dopamine “D2” receptors. Net action of the degeneration of dopanigeneric neurons in the SNc leads to the hyper-activation of the BG output nuclei (GPi/SNr) inhibiting activities of thalamocortical projection neurons, which in turn negatively affects motor output [for more detail, see DeLong (1990), Wichmann and DeLong (1996), Blandini et al. (2000), Galvan and Wichmann (2008), and Smith et al. (2012)].

Bottom Line: For example, the mere presence of an underlying beat or pulse can result in spontaneous motor responses such as hand clapping, foot stepping, and rhythmic vocalizations.Here, we propose the "SEP" hypothesis, which postulates that (1) "sound envelope processing" and (2) "synchronization and entrainment to pulse" may help stimulate brain networks that underlie human communication.Ultimately, we hope that the SEP hypothesis will provide a useful framework for facilitating rhythm-based research in various patient populations.

View Article: PubMed Central - PubMed

Affiliation: Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Sunnybrook Research Institute , Toronto, ON , Canada.

ABSTRACT
For thousands of years, human beings have engaged in rhythmic activities such as drumming, dancing, and singing. Rhythm can be a powerful medium to stimulate communication and social interactions, due to the strong sensorimotor coupling. For example, the mere presence of an underlying beat or pulse can result in spontaneous motor responses such as hand clapping, foot stepping, and rhythmic vocalizations. Examining the relationship between rhythm and speech is fundamental not only to our understanding of the origins of human communication but also in the treatment of neurological disorders. In this paper, we explore whether rhythm has therapeutic potential for promoting recovery from speech and language dysfunctions. Although clinical studies are limited to date, existing experimental evidence demonstrates rich rhythmic organization in both music and language, as well as overlapping brain networks that are crucial in the design of rehabilitation approaches. Here, we propose the "SEP" hypothesis, which postulates that (1) "sound envelope processing" and (2) "synchronization and entrainment to pulse" may help stimulate brain networks that underlie human communication. Ultimately, we hope that the SEP hypothesis will provide a useful framework for facilitating rhythm-based research in various patient populations.

No MeSH data available.


Related in: MedlinePlus