Table 1 Cerebellar Transcranial Direct Current Stimulation (tDCS) studies
From: Cerebellar transcranial direct current stimulation in neurological disease
Author & year | Sample | Trial type | Polarity and number of sessions | Stimulation electrode position | Reference electrode position | Current strength and duration | Outcome | Online/Offline procedure | Follow-up | Results |
|---|---|---|---|---|---|---|---|---|---|---|
Parkinson’s disease | ||||||||||
Ferrucci et al. (2015) [47] | N = 9 (74.3 ± 8) | Randomized, double blind, cross-over | A/S 5 daily tDCS | Whole cerebellum or bilateral M1 | Right deltoid muscle | 2 mA, 20 min | UPDRS (III-IV), PDQ8, BDI, word recall, spatial cueing, SRTT | Offline | 1–4 week | A tDCS over M1 and cerebellum improved: UPDRS(dyskinesia section) score by about 20 %. |
Dystonia | ||||||||||
Sadnicka et al. (2014) [50] | N = 10 (not reported) | Randomized, double-blind | A/S single tDCS | Right cerebellar cortex | Right buccinator muscle | 2 mA, 15 min | RMT, AMT, RC, CSP, VAS | Offline | No | Negative |
Bradnam et al. (2015) [48] | N = 16 8 patients (59 ± 13) 8 healthy subjects (61.21 ± 11.73) | Randomized, double-blind | A/C/S single tDCS | Right cerebellar cortex | Right buccinator muscle | 2 mA, 20 min | ADDS, WCRS, MEPs, MFS, APP | Offline | No | A tCDCS improved: APP by 12.81 %. A-C tDCS reduced handwriting MSF (A: 8.47 %; C: 9.6 %). |
Essential Tremor | ||||||||||
Gironell et al. (2014) [51] | N = 10 (71.4 not reported) | Randomized, double blind, cross-over | C/S 5daily tDCS | Bilateral cerebellar cortex | Fp 1, Fp2 | 2 mA, 20 min | TCRS, accelometric recording, self-reporteddisability scale | Offline | 4 weeks | Negative |
Cerebellar Ataxia | ||||||||||
Grimaldi et al. (2013) [52] | N = 9 (mean age 51.3 ± 14) | Single blind, sham-controlled | A/S | Right cerebellar cortex, vermis | Contralateral supra-orbital area | 1 mA, 20 min | SR, MCT, Computerized Posturography | Offline | No | A tCDCS reduced the amplitudes of long-latency stretch reflexes |
Grimaldi et al. (2014) [53] | N = 2 (mean age 46 ± 4.24) | Single blind, sham-controlled | A/S | Right cerebellar cortex, Left M1 | Contralateral supra-orbital area, right supra-orbital area | 1 mA, 20 + 20 min | SARA, Upper limb tremor (postural and action tremor), dysmetria | Offline | No | A tCCDCS reduced: the PSD peak by 38.63 and 41.42 % in both patients, the magnitude of low frequency oscillations by 46.9 and 62.3 % respectively, and the onset latency of the hypermetria by about 41 and 45 %. |
Benussi et al. (2015) [54] | N = 19 (mean age 53.8 ± 18.4) | Randomized, double blind, cross-over; sham-controlled | A/S | Cerebellar cortex | Right deltoid muscle | 2 mA 20 min | SARA, ICARS, 9HPT, 8 MW | offline | No | A tCDCS improved: SARA by about 10 %, ICARS by 12 %, 9HPT by 11 %, 8 MW by 11 %. |