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tDCS of the Cerebellum: Where Do We Stand in 2016? Technical Issues and Critical Review of the Literature.

van Dun K, Bodranghien FC, Mariën P, Manto MU - Front Hum Neurosci (2016)

Bottom Line: Transcranial Direct Current Stimulation (tDCS) is an up-and-coming electrical neurostimulation technique increasingly used both in healthy subjects and in selected groups of patients.Due to the high density of neurons in the cerebellum, its peculiar anatomical organization with the cortex lying superficially below the skull and its diffuse connections with motor and associative areas of the cerebrum, the cerebellum is becoming a major target for neuromodulation of the cerebellocerebral networks.We provide a comparison with transcranial Alternating Current Stimulation (tACS), another promising transcranial electrical neurostimulation technique.

View Article: PubMed Central - PubMed

Affiliation: Clinical and Experimental Neurolinguistics, Vrije Universiteit Brussel Brussels, Belgium.

ABSTRACT
Transcranial Direct Current Stimulation (tDCS) is an up-and-coming electrical neurostimulation technique increasingly used both in healthy subjects and in selected groups of patients. Due to the high density of neurons in the cerebellum, its peculiar anatomical organization with the cortex lying superficially below the skull and its diffuse connections with motor and associative areas of the cerebrum, the cerebellum is becoming a major target for neuromodulation of the cerebellocerebral networks. We discuss the recent studies based on cerebellar tDCS with a focus on the numerous technical and open issues which remain to be solved. Our current knowledge of the physiological impacts of tDCS on cerebellar circuitry is criticized. We provide a comparison with transcranial Alternating Current Stimulation (tACS), another promising transcranial electrical neurostimulation technique. Although both tDCS and tACS are becoming established techniques to modulate the cerebellocerebral networks, it is surprising that their impacts on cerebellar disorders remains unclear. A major reason is that the literature lacks large trials with a double-blind, sham-controlled, and cross-over experimental design in cerebellar patients.

No MeSH data available.


Related in: MedlinePlus

Cerebellar folding influences polarization along the sulci. The principal axis of the Purkinje cells (indicated with blue arrows—the color code has no particular significance in the inset) along a trace of cerebellar gyri is subject to an electric field. The resulting polarization (maximal hyperpolarization or depolarization) is indicated in false color along the trace. Adapted from Rahman et al. (2014). With permission from Elsevier.
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Figure 2: Cerebellar folding influences polarization along the sulci. The principal axis of the Purkinje cells (indicated with blue arrows—the color code has no particular significance in the inset) along a trace of cerebellar gyri is subject to an electric field. The resulting polarization (maximal hyperpolarization or depolarization) is indicated in false color along the trace. Adapted from Rahman et al. (2014). With permission from Elsevier.

Mentions: As expected, the effects of tDCS critically depend on (a) the previous neuronal physiological state and (b) the structure orientation relative to the electric field direction (Bikson et al., 2004; Manola et al., 2005; Woods et al., 2016). Neurons of the cerebellum are not identically orientated and even follow complex anatomical distributions over the numerous folia. This will cause a hyperpolarization in some compartments while others will be depolarized at the same time (Figure 2). Therefore, the global effects of tDCS on the cerebellum remain difficult to simulate (Woods et al., 2016). The linking function of parallel fibers in the cerebellar cortex and the peculiar disposition of the 10 lobules of the cerebellum surrounded by CSF and vessels render the simulation even more difficult.


tDCS of the Cerebellum: Where Do We Stand in 2016? Technical Issues and Critical Review of the Literature.

van Dun K, Bodranghien FC, Mariën P, Manto MU - Front Hum Neurosci (2016)

Cerebellar folding influences polarization along the sulci. The principal axis of the Purkinje cells (indicated with blue arrows—the color code has no particular significance in the inset) along a trace of cerebellar gyri is subject to an electric field. The resulting polarization (maximal hyperpolarization or depolarization) is indicated in false color along the trace. Adapted from Rahman et al. (2014). With permission from Elsevier.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4862979&req=5

Figure 2: Cerebellar folding influences polarization along the sulci. The principal axis of the Purkinje cells (indicated with blue arrows—the color code has no particular significance in the inset) along a trace of cerebellar gyri is subject to an electric field. The resulting polarization (maximal hyperpolarization or depolarization) is indicated in false color along the trace. Adapted from Rahman et al. (2014). With permission from Elsevier.
Mentions: As expected, the effects of tDCS critically depend on (a) the previous neuronal physiological state and (b) the structure orientation relative to the electric field direction (Bikson et al., 2004; Manola et al., 2005; Woods et al., 2016). Neurons of the cerebellum are not identically orientated and even follow complex anatomical distributions over the numerous folia. This will cause a hyperpolarization in some compartments while others will be depolarized at the same time (Figure 2). Therefore, the global effects of tDCS on the cerebellum remain difficult to simulate (Woods et al., 2016). The linking function of parallel fibers in the cerebellar cortex and the peculiar disposition of the 10 lobules of the cerebellum surrounded by CSF and vessels render the simulation even more difficult.

Bottom Line: Transcranial Direct Current Stimulation (tDCS) is an up-and-coming electrical neurostimulation technique increasingly used both in healthy subjects and in selected groups of patients.Due to the high density of neurons in the cerebellum, its peculiar anatomical organization with the cortex lying superficially below the skull and its diffuse connections with motor and associative areas of the cerebrum, the cerebellum is becoming a major target for neuromodulation of the cerebellocerebral networks.We provide a comparison with transcranial Alternating Current Stimulation (tACS), another promising transcranial electrical neurostimulation technique.

View Article: PubMed Central - PubMed

Affiliation: Clinical and Experimental Neurolinguistics, Vrije Universiteit Brussel Brussels, Belgium.

ABSTRACT
Transcranial Direct Current Stimulation (tDCS) is an up-and-coming electrical neurostimulation technique increasingly used both in healthy subjects and in selected groups of patients. Due to the high density of neurons in the cerebellum, its peculiar anatomical organization with the cortex lying superficially below the skull and its diffuse connections with motor and associative areas of the cerebrum, the cerebellum is becoming a major target for neuromodulation of the cerebellocerebral networks. We discuss the recent studies based on cerebellar tDCS with a focus on the numerous technical and open issues which remain to be solved. Our current knowledge of the physiological impacts of tDCS on cerebellar circuitry is criticized. We provide a comparison with transcranial Alternating Current Stimulation (tACS), another promising transcranial electrical neurostimulation technique. Although both tDCS and tACS are becoming established techniques to modulate the cerebellocerebral networks, it is surprising that their impacts on cerebellar disorders remains unclear. A major reason is that the literature lacks large trials with a double-blind, sham-controlled, and cross-over experimental design in cerebellar patients.

No MeSH data available.


Related in: MedlinePlus