Table 3.
Multiple linear regression model summary for the principal neurometabolite predictors of GoRT (young and old) and SSRT (old)
| Performance/Age group | R 2 | R 2-Adj. | F | Contributing neurometabolite | R 2 change‡ | β (SE) | B (SE) | P value |
|---|---|---|---|---|---|---|---|---|
| GoRT YA | 0.580 | 0.520 | 9.657** | |||||
| Intercept | 760.3 (23.10) | 0.0000 | ||||||
| LSTR [Glx] ↓ | 0.162 | −0.427 (0.150) | −1.954 (0.686) | 0.0097 | ||||
| RSTR [Glx] ↑ | 0.111 | 0.353 (0.150) | 2.078 (0.883) | 0.0284 | ||||
| RSM1 [NAA] ↑ | 0.128 | 0.360 (0.142) | 8.621 (3.407) | 0.0194 | ||||
| GoRT OA | 0.399 | 0.317 | 4.868** | |||||
| Intercept | 702.9 (36.57) | 0.0000 | ||||||
| LSM1 [NAA] | 0.072 | 0.306 (0.188) | 8.809 (5.421) | 0.1184 | ||||
| LSTR [NAA] | 0.066 | 0.286 (0.184) | 9.687 (6.227) | 0.1340 | ||||
| RSM1 [mIns] | 0.053 | 0.247 (0.178) | 7.783 (5.614) | 0.1795 | ||||
| SSRT OA | 0.463 | 0.416 | 9.898*** | |||||
| Intercept | 105.6 (26.93) | 0.0007 | ||||||
| OCC [mIns] ↑ | 0.254 | 0.514 (0.156) | 30.97 (9.397) | 0.0032 | ||||
| RSM1 [NAA] ↑ | 0.122 | 0.356 (0.156) | 9.909 (4.336) | 0.0318 |
Notes: Directions of associations between performance measures and models’ principal neurometabolite predictors are indicated: (↑) for positive association and (↓) for negative association; significant associations (P values < 0.05) are indicated in bold. Multiple regression model R2, Adjusted R2 (R2-Adj), and F-value (P levels: *P < 0.05; **P < 0.01; ***P < 0.001); B, regression coefficient; β, standardized regression coefficient; SE, standard error. Abbreviations: NAA, N-acetylaspartate; Glx, glutamate–glutamine complex; mIns, myo-inositol; RSM1, right sensorimotor cortex; RSTR, right striatum; LSM1, left sensorimotor cortex; LSTR, left striatum; OCC, occipital cortex.
‡ R 2 change represent the amount by which R2 is reduced if a particular independent variable is removed from the model.