Table 3. Means and standard deviations of digit span forwards (phonological loop) and backwards (central executive/executive functions); letter memory (executive function); Stroop 1, Stroop 2, and Stroop 3 (central executive/executive function); Trail A and Trail B (central executive/executive functions); Corsi forwards (visuospatial sketchpad) and backwards (central executive/executive function) from the measures for the OSPAN test (visuospatial sketchpad); and random number generation test (central executive/executive function).
| Tests | Methylphenidate | F/H | P | |||
|---|---|---|---|---|---|---|
| Placebo | 10 mg | 20 mg | 40 mg | |||
| Digit Span Forwards | 6.33 ± 1.32 | 5.77 ± 1.09 | 7.11 ± 1.26 | 7.22 ± 0.66 | 2.58 | 0.07 |
| Digit Span Backwards | 6.11 ± 1.61 | 5.11 ± 1.26 | 5.88 ± 1.05 | 6.33 ± 1.11 | 1.54 | 0.25 |
| Letter Memory | 9.33 ± 3.31 | 9.33 ± 3.93 | 8.55 ± 2.18 | 8.55 ± 2.55 | 0.19 | 0.90 |
| Stroop 1 | 47.55 ± 11.86 | 50.44 ± 10.91 | 46.55 ± 9.68 | 47.55 ± 9 | 0.23 | 0.87 |
| Stroop 2 | 54.33 ± 12.45 | 58,33 ± 12.12 | 52 ± 9.88 | 54.11 ± 10.75 | 0.48 | 0.69 |
| Stroop 3 | 71 ± 14.3 | 76.77 ± 6.27 | 66.77 ± 13.76 | 68.11 ± 15.92 | 0.89 | 0.45 |
| Trail A | 28.77 ± 9.07 | 25.88 ± 4.13 | 25.88 ± 4.13 | 28.5 ± 12.46 | 0.31 | 0.81 |
| Trail B | 48.77 ± 14.83 | 59.88 ± 19.71 | 60 ± 35.97 | 58 ± 20.74 | 0.43 | 0.72 |
| Corsi Forwards | 6.88 ± 1.69 | 6.44 ± 1.13 | 6.55 ± 0.88 | 6.33 ± 1.11 | 0.33 | 0.79 |
| Corsi Backwards | 6 ± 1.41 | 6.33 ± 1.5 | 5.77 ± 0.83 | 6.55 ± 1.5 | 0.59 | 0.62 |
| OSPAN - Sums | 0.99 ± 0.01 | 0.98 ± 0.01 | 0.98 ± 0.02 | 0.98 ± 0.01 | 0.36 | 0.78 |
| OSPAN - Serial Recall | 0.56 ± 0.17 | 0.58 ± 0.19 | 0.67 ± 0.16 | 0.59 ± 0.18 | 0.63 | 0.59 |
| OSPAN - Free Recall | 0.71 ± 0.1 | 0.75 ± 0.11 | 0.78 ± 0.11 | 0.73 ± 0.1 | 0.67 | 0.57 |
| RNG - Evans Index | 0.32 ± 0.04 | 0.31 ± 0.02 | 0.33 ± 0.02 | 0.31 ± 0.03 | 1.03 | 0.38 |
| RNG - Coupon | 17.00 ± 4.96 | 18.77 ± 7.71 | 17.53 ± 5.15 | 17.74 ± 2.31 | 0.17 | 0.91 |
| RNG - TPI* | 98.63 ± 9.71 | 94.65 ± 13.08 | 95.91 ± 8.2 | 98.36 ± 7.89 | 0.33 | 0.79 |
| RNG - Runs | 0.89 ± 0.27 | 0.89 ± 0.28 | 0.81 ± 0.2 | 0.87 ± 0.19 | 0.19 | 0.90 |
| RNG - Average | 8.78 ± 0.14 | 8.69 ± 0.23 | 8.68 ± 0.41 | 8.73 ± 0.11 | 0.28 | 0.83 |
| RNG - Preferred | 15.11 ± 1.83 | 15.00 ± 1.8 | 14.88 ± 1.61 | 13.22 ± 2.86 | 1.65 | 0.19 |
| RNG - Less Preferred | 7.22 ± 1.71 | 6.67 ± 1.58 | 7.11 ± 2.31 | 8.00 ± 2.29 | 0.68 | 0.56 |
| RNG - Errors | 2.66 ± 3.39 | 4.55 ± 5.61 | 3.11 ± 4.25 | 4.77 ± 4.79 | 0.46 | 0.70 |
| Zoo - Score (I**) | 6.33 ± 2.5 | 6.88 ± 2.2 | 7.44 ± 1.33 | 6.44 ± 2.45 | 0.92 | 0.82 |
| Zoo - Planning (I**) | 73.77 ± 39.19 | 100 ± 65.48 | 50 ± 25.83 | 121.66 ± 129.07 | 3.52 | 0.31 |
| Zoo - Total Time (I**) | 145 ± 105.67 | 138.44 ± 71.45 | 82 ± 33.99 | 163.11 ± 137.61 | 4.32 | 0.22 |
| Zoo - Score (II#) | 8.00 ± 0 | 8.00 ± 0 | 7.88 ± 0.33 | 8.00 ± 0 | 3.00 | 0.39 |
| Zoo - Time (II#) | 31.66 ± 9.68 | 33.88 ± 14.47 | 32.77 ± 12.98 | 35 ± 14.71 | 0,29 | 0.96 |
*TPI: Turning Point Index; **I: First part, with high cognitive demand; #II: Second part, with low cognitive demand.