Table 1.
Results for the main hierarchical linear regression models and follow-up models of the associations between left and right superior longitudinal fasciculus/arcuate fasciculus (SLF/AF) fractional anisotropy (FA) and semantic or phonemic fluency performance.
| Age | Sex | Left SLF/AF FA | Right SLF/AF FA | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Main Hypothesesa | R2 (df) | ß | p | ß | p | ß | p | ß | p |
| Semantic Fluency | |||||||||
| Reduced Model | 0.32 (70) | 0.57 | <0.001 | −0.16 | 0.43 | -- | -- | ||
| Full Model | 0.40 (68) | 0.48 | <0.001 | −0.18 | 0.35 | −0.09 | 0.53 | 0.38 | 0.008 |
| Model Comparison | ΔR2 = 0.08; χ2 (2, N = 73) = 5.7, p = 0.005* | ||||||||
| Phonemic Fluency | |||||||||
| Reduced Model | 0.27 (70) | 0.49 | <0.001 | 0.23 | 0.25 | -- | -- | -- | -- |
| Full Model | 0.34 (68) | 0.51 | <0.001 | 0.33 | 0.11 | −0.34 | 0.03 | 0.44 | 0.003 |
| Model Comparison | ΔR2 = 0.07; χ2 (2, N = 73) = 4.6, p = 0.01* | ||||||||
| Follow-up Modelsb | |||||||||
| Semantic Fluency | |||||||||
| Right SLF/AF FA | 0.40 (69) | 0.46 | <0.001 | −0.22 | 0.235 | -- | -- | 0.32 | 0.001 |
| Left SLF/AF FA | 0.34 (69) | 0.49 | <0.001 | −0.26 | 0.194 | 0.201 | 0.063 | -- | -- |
| Phonemic Fluency | |||||||||
| Right SLF/AF FA | 0.30 (69) | 0.46 | <0.001 | 0.19 | 0.343 | -- | -- | 0.21 | 0.046 |
| Left SLF/AF FA | 0.26 (69) | 0.53 | <0.001 | 0.23 | 0.275 | −0.001 | 0.993 | -- | -- |
The results of the likelihood-ratio chi-square tests of the R2 change between the full and reduced models are shown below each model coefficients. * Below Bonferroni corrected α (p < 0.025) for two main hypotheses.
a
Left and right SLF/AF FA are in the same model.
b
Left and right SLF/AF FA are in separate models.