Table 1.
Demographic, clinical, and behavioural characteristics
| Sham (N = 17) | Verum (N = 16) | p value | |
|---|---|---|---|
| Demographics | |||
| Age (years) | 57 ± 10 (41–70) | 55 ± 9 (39–75) | .61a |
| Gender (% men) | 11 (65%) | 9 (56%) | .62b |
| Educatione | 6 (3–7) | 6 (4–7) | .04b |
| IQ estimation | 110 ± 14 (82–130) | 98 ± 12 (73–123) | .01a |
| Handedness (right) | 16 (94%) | 14 (88%) | .60c |
| Clinical measures | |||
| MMSE | 29 (27–30) | 29 (28–30) | .36d |
| BDI | 1 (0–4) | 2 (0–10) | .33d |
| BAI | 1 (0–5) | 1 (0–11) | .61d |
| Stimulation measures | |||
| Interval session 1–session 2 (days) | 14 (7–35) | 15 (6–28) | .93d |
| Interval stimulation–task (s) | 356 (277–800) | 319 (240–488) | .053d |
| Behavioural measures | |||
| Session 1: RT correct repeat trials (ms) | 820 ± 201 (503–1,182) | 849 ± 212 (540–1,269) | |
| Session 2: RT correct repeat trials (ms) | 738 ± 210 (483–1,167) | 803 ± 191 (479–1,150) | |
| Session 1: RT correct switch trials (ms) | 901 ± 210 (519–1,286) | 927 ± 230 (623–1,354) | |
| Session 2: RT correct switch trials (ms) | 842 ± 240 (541–1,286) | 901 ± 244 (517–1,324) | |
| Session 1: Switch costs (ms) | 68 (−24–341) | 61 (−23–269) | |
| Session 2: Switch costs (ms) | 107 (−5–201) | 79 (1–234) | |
| Session 1: Failed repeat trials (% of total) | .76 (0–4.08) | .73 (0–4.21) | |
| Session 2: Failed repeat trials (% of total) | .71 (0–4.78) | .55 (0–3.51) | |
| Session 1: Failed switch trials (% of total) | .37 (0–3.79) | .18 (0–2.19) | |
| Session 2: Failed switch trials (% of total) | 0 (0–1.76) | .74 (0–3.51) | |
Values are presented as mean ± standard deviation or median (range) unless indicated otherwise.
MMSE mini-mental state examination, BDI Beck depression inventory, BAI Beck anxiety inventory.
aIndependent samples t test.
bPearson’s χ2 test.
cFisher’s exact test.
dIndependent samples Mann–Whitney U test.
eEducation level was measured in 7 levels ranging from 1 (no finished education) to 7 (university training).