Table 4.
Associations Between Age and White Matter Tracts
| FA: p-values | r | RD: p-values | r | AD: p-values | r | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Working Memory Tracts | left | right | left | right | left | right | left | right | left | right | left | right |
| CC Genu | 0.006 | .36 | 0.004 | −.36 | 0.306 | |||||||
| Ant. Cingulum | 0.052 | 0.116 | 0.018 | 0.043 | −.31 | 0.674 | 0.450 | |||||
| Ant. Thalamic Radiation | 0.018 | 0.011 | .28 | .30 | 0.003 | 0.005 | −.34 | −.34 | 0.237 | 0.528 | ||
| Sup. Thalamic Radiation | 0.069 | 0.073 | 0.032 | 0.006 | −.34 | 0.554 | 0.134 | |||||
| Arcuate Fasciculus | 0.121 | 0.042 | 0.051 | 0.026 | 0.560 | 0.733 | ||||||
| Temporal-Parietal Seg. | 0.299 | 0.165 | 0.009 | 0.034 | −.31 | 0.206 | 0.632 | |||||
| Control Tracts | ||||||||||||
| CC Splenium | 0.286 | 0.152 | 0.513 | |||||||||
| CC Body | 0.092 | 0.140 | 0.777 | |||||||||
| Inf. Long. Fasciculus | 0.128 | 0.425 | 0.511 | 0.958 | 0.171 | 0.639 | ||||||
| Spinothalamic Radiation | 0.144 | 0.066 | 0.083 | 0.013 | −.35 | 0.475 | 0.147 | |||||
| Optic Nerve | 0.163 | 0.708 | 0.664 | 0.191 | 0.954 | 0.253 | ||||||
A mixed linear regression model was used to analyze diffusion indices (FA, RD, AD) in each fiber tract, including all tracts as dependent variables, with gender, age, non-verbal developmental quotient, verbal developmental quotient, and working memory performance as predictor variables. Table shows uncorrected p-values, bolded values show significant associations between white matter and infants’ age (adjusted for gestational length), after correcting for multiple comparisons. Partial correlations provide a measure of effect size for significant associations.