Anodal tDCS over Primary Motor Cortex Provides No Advantage to Learning Motor Sequences via Observation

Table 2

Frequencies of self-reported sensations during the training sessions.

(a) The strongest intensity of discomforting sensations

Intensity level	Day 1						Day 2						Day 3						Day 4
	0	1	2	3	4		0	1	2	3	4		0	1	2	3	4		0	1	2	3	4
Sham	1	12	10	1	—		4	11	8	1	—		2	15	7	—	—		5	14	5	—	—
Active	2	11	8	3	2		2	18	2	3	1		2	15	4	2	3		3	16	5	2	—

0: none; 1: mild; 2: moderate; 3: considerable; 4: strong.

(b) How much did the sensations affect performance?

Intensity level	Day 1						Day 2						Day 3						Day 4
	0	1	2	3	4		0	1	2	3	4		0	1	2	3	4		0	1	2	3	4
Sham	19	5	—	—	—		20	4	—	—	—		22	2	—	—	—		21	2	1	—	—
Active	18	7	—	1	—		20	6	—	—	—		18	7	1	—	—		20	6	—	—	—

0: not at all; 1: slightly; 2: considerably; 3: much; 4: very much.

(c) When did the discomfort stop?

Intensity level	Day 1					Day 2					Day 3					Day 4
	ns	1	2	3		ns	1	2	3		ns	1	2	3		ns	1	2	3
Sham	1	15	4	4		4	14	4	2		2	19	3	—		5	18	—	1
Active	2	6	9	9		2	11	7	6		2	8	7	9		3	9	8	6

ns: no sensations; 1: quickly; 2: middle of the block; 3: end of the block.