Table 1.
Demographic characteristics of the study sample.
| PLE-0 (N = 41) | PLE-1 (N = 19) | PLE-2 (N = 26) | Statistics | |
|---|---|---|---|---|
| Demographic | ||||
| Age (SE) | 17.22 (0.11) | 17.37 (0.19) | 17.31 (0.17) | F = 0.25; p = 0.78 |
| Sex, % male | 46.3 | 42.11 | 53.84 | χ2 = 0.66; p = 0.72 |
| Handedness, % right-handed | 97.56 | 94.74 | 96.15 | χ2 = 0.851; p = 0.85 |
| Substance use (12 m) | ||||
| Cannabis use level (SE) | 0.87 (0.21) | 1.5 (0.41) | 1.3 (0.18) | F = 1.18; p = 0.313 |
| Alcohol use level (SE) | 2 (0.16) | 2.61* (0.20) | 1.56* (0.23) | F = 5.68; p = 0.005 |
| Tobacco use level (SE) | 0.76 (0.25) | 1.39 (0.40) | 0.74 (0.36) | F = 1.05; p = 0.356 |
| Theory of Mind task results | ||||
| Second-order mentalizing (SD) | 88.25% (6.91) | 87.78% (7.75) | 88.23% (5.62) | F = 0.03; p = 0.97 |
| Non-social reasoning control (SD) | 92.59% (8.40) | 95.10% (8.87) | 95.33% (6.84) | F = 1.05; p = 0.35 |
| First-order inference control (SD) | 96.76% (9.61) | 100% (0) | 97.33% (9.23) | F = 0.89; p = 0.42 |
| Attention and memory control (SD) | 99.43% (1.30) | 95.88% (1.94) | 95.33% (2.44) | F = 1.38; p = 0.26 |
| False positive control (SD) | 86.11% (22.71) | 91.17% (19.65) | 82% (28.43) | F = 0.74; p = 0.48 |
SE = Standard Error; SD = Standard Deviation; Substance use rated on a 6-point scale; The theory of mind task looked at stories of false belief which served as a measure of second-order mentalizing, control items tested non-social reasoning, first-order inference, questions to control for attention and memory effect, and items to control for false-positives. Mean percentage of correct answers in each category.
PLE-0 = control trajectory; PLE-1 = decreasing trajectory; PLE-2 = increasing trajectory.
*Significant difference.