Means (SD) across tyrosine supplementation and non-supplementation2-150 phases, together with the confidence intervals and standard errors for the mean differences between the conditions
| Measure | Tyrosine | Non-supplementation2-150 | t (df) | p | Confidence interval | SE |
|---|---|---|---|---|---|---|
| Conflicting motor task | ||||||
| Number of errors | 5.07 (2.72) | 5.69 (2.47) | −1.24 (1,20) | 0.23 | −1.13 to −0.12 | 0.51 |
| Delay task | ||||||
| Number correct | 50.31 (13.53) | 46.60 (12.67) | 1.76 (1,17) | 0.10 | 1.59 to 5.81 | 2.11 |
| Efficiency ratio | 0.81 (0.16) | 0.80 (0.17) | 0.42 (1,17) | 0.68 | −0.02 to 0.05 | 0.04 |
| Simple RT task | ||||||
| Reaction time (ms) | 624.0 (119.7) | 619.5 (139.0) | 0.42 (1,18) | 0.68 | −6.17 to 15.11 | 10.64 |
| Number correct max=30 | 27.16 (3.73) | 27.03 (3.64) | 0.27 (1,18) | 0.79 | −0.35 to 0.61 | 0.48 |
| Errors of commission | 4.58 (9.27) | 4.65 (9.61) | −0.05 (1,18) | 0.96 | −1.44 to 1.30 | 1.37 |
| Vigilance RT task | ||||||
| Reaction time (ms) | 454.3 (96.6) | 469.9 (99.0) | −1.33 (1,20) | 0.20 | −27.35 to −3.93 | 11.70 |
| Number correct max=45 | 39.45 (6.25) | 39.96 (4.55) | −0.76 (1,20) | 0.46 | −1.18 to 0.16 | 0.67 |
| Errors of commission | 6.74 (8.77) | 7.65 (8.53) | −0.83 (1,20) | 0.42 | −2.01 to 0.19 | 1.10 |
| Self ordered pointing task | ||||||
| Number of errors | 12.55 (6.72) | 12.16 (6.52) | 0.37 (1,20) | 0.72 | −0.66 to 1.44 | 1.05 |
| Short term memory task | ||||||
| Distraction condition | 35.50 (11.85) | 35.52 (11.85) | 1.27 (1,7) | 0.25 | 0.63 to 5.32 | 2.35 |
| No distraction condition | 76.56 (3.33) | 76.88 (4.68) | −0.23 (1,7) | 0.83 | −1.69 to 1.07 | 1.38 |
↵2-150 Non-supplementation consists of the average of performance during baseline and L-alanine phases.
df = degrees of freedom; RT = reaction time.