Table 2.
Sleep spindle characteristics in all experimental groups
| PP |
MI |
AO |
ANOVAs |
|||||
|---|---|---|---|---|---|---|---|---|
| mean | SEM | mean | SEM | mean | SEM | F | p | |
| Total amount of spindles | 174.5 | 21.1 | 185.3 | 21.5 | 164.7 | 22.8 | 0.22 | 0.80 |
| Grouped spindles | 145.5 | 19.3 | 151.3 | 17.8 | 138.3 | 19.2 | 0.12 | 0.89 |
| Isolated spindles | 29.0 | 3.2 | 34.0 | 5.0 | 26.4 | 4.4 | 0.81 | 0.45 |
| Number of trains | 36.9 | 4.4 | 38.7 | 4.0 | 34.4 | 4.8 | 0.24 | 0.80 |
| Inter-spindle interval (ISI) | 3.4 | 0.1 | 3.5 | 0.1 | 3.5 | 0.1 | 0.03 | 0.97 |
| Inter-train interval (ITI) | 44.8 | 4.2 | 46.0 | 2.4 | 41.1 | 2.2 | 0.69 | 0.51 |
| Global density | 7.1 | 0.4 | 6.3 | 0.4 | 6.5 | 0.3 | 1.28 | 0.29 |
| Local density | 8.8 | 0.5 | 8.1 | 0.4 | 8.6 | 0.4 | 0.80 | 0.46 |
Means and standard errors of the means (SEM) are reported for the total number of spindles, grouped spindles, isolated spindles, the number of trains, inter-spindle interval (ISI), inter-train interval (ITI), global density (number of spindles per minute), and local density (number of spindles within a spindle-centered 60 s sliding window) of NREM2 sleep spindles at the Pz electrode (midline parietal) during the 90-min daytime nap for each of the physical practice (n = 15), motor imagery (n = 15) and action observation (n = 15) groups. The results of the one-way ANOVAs (F and p values) are also reported. PP, Physical practice; MI, Motor imagery; AO, Action observation.