Table 6.
Model coefficients for the best-fitting GAMMs of the left fronto-basal-ganglia circuit.
| Left IFG-preSMA (logFC) | |||
| Parametric coefficients | Est. (SE) | t | pFDR |
| Intercept | 0.023 (0.009) | 2.490 | 0.039 |
| SES_c | 0.0002 (0.0002) | 0.844 | 0.535 |
| FWD_c | -0.007 (0.009) | -0.832 | 0.539 |
| eTIV_c | 0.002 (0.0004) | 5.327 | < 0.001 |
| OFscanner | -0.031 (0.006) | -4.896 | < 0.001 |
| Smooth terms | edf (Ref.df) | F | pFDR |
| s(age_c) | 1.031 (1.061) | 25.488 | < 0.001 |
| s(SID) | 68.477 (71.000) | 53.479 | < 0.001 |
| Left preSMA-STN (logFC) | |||
| Parametric coefficients | Est. (SE) | t | pFDR |
| Intercept | 0.013 (0.009) | 1.476 | 0.252 |
| SES_c | 0.0002 (0.0002) | 1.056 | 0.424 |
| FWD_c | 0.009 (0.010) | 0.952 | 0.474 |
| eTIV_c | 0.002 (0.0003) | 6.661 | < 0.001 |
| OFscanner | -0.035 (0.007) | -5.187 | < 0.001 |
| Smooth terms | edf (Ref.df) | F | pFDR |
| s(age_c) | 1.000 (1.001) | 32.095 | < 0.001 |
| s(SID) | 67.932 (71.000) | 37.538 | < 0.001 |
Note: Left IFG-preSMA (logFC): Log-transformed fiber cross-section of the left inferior frontal-gyrus to presupplementary motor area connection; Left preSMA-STN (logFC): Log-transformed fiber cross-section of the left presupplementary motor area to subthalamic nucleus connection; Est.: Estimated regression parameter; SE: Standard error; edf: Estimated degrees of freedom; Ref.df: Reference degrees of freedom; pFDR: False Discovery Rate corrected p value; s(age_c): Smoothed mean-centred age; SES_c: Mean-centred SES; s(SID): Subject ID entered as a random effect; FWD_c: Mean-centred FWD; eTIV_c: Mean-centred eTIV; OFscanner: Ordered factor of scanner type.