Table 3.
Region | Estimate | Standard error | t-value | P-value |
---|---|---|---|---|
Executive function | ||||
ATR | 0.010 | 0.010 | 0.982 | 0.163 |
CB | 0.026 | 0.011 | 2.326 | 0.010 |
PHC | −0.006 | 0.009 | −0.715 | 0.737 |
CST | −0.003 | 0.010 | −0.270 | 0.894 |
Fma | 0.005 | 0.011 | 0.466 | 0.321 |
Fmi | 0.007 | 0.012 | 0.587 | 0.279 |
IFOF | 0.013 | 0.015 | 0.871 | 0.192 |
ILF | −0.023 | 0.011 | −2.089 | 0.518 |
SLF | −0.012 | 0.014 | −0.912 | 0.681 |
Episodic memory | ||||
ATR | 0.009 | 0.014 | 0.603 | 0.273 |
CB | 0.025 | 0.016 | 1.563 | 0.059 |
PHC | −0.008 | 0.012 | −0.608 | 0.772 |
CST | −0.006 | 0.014 | −0.450 | 0.826 |
Fma | 0.005 | 0.015 | 0.346 | 0.365 |
Fmi | 0.023 | 0.017 | 1.359 | 0.087 |
IFOF | −0.013 | 0.021 | −0.620 | 0.768 |
ILF | −0.006 | 0.016 | −0.406 | 0.842 |
SLF | 0.012 | 0.019 | 0.636 | 0.263 |
Processing speed | ||||
ATR | 0.021 | 0.012 | 1.820 | 0.035 |
CB | 0.007 | 0.013 | 0.501 | 0.308 |
PHC | −0.005 | 0.010 | −0.517 | 0.803 |
CST | −0.011 | 0.012 | −0.919 | 0.679 |
Fma | 0.015 | 0.012 | 1.173 | 0.121 |
Fmi | 0.012 | 0.014 | 0.901 | 0.184 |
IFOF | 0.036 | 0.017 | 2.109 | 0.018 |
ILF | 0.004 | 0.013 | 0.310 | 0.379 |
SLF | −0.036 | 0.015 | −2.320 | 0.510 |
Each row summarizes the results from a separate linear mixed model that examines the contribution of each tract over and above a global measure of white matter microstructure to longitudinal cognitive change. All models control for age, sex, education, motion in the scanner, modified global FA, amyloid status, and their interactions with time. The modified global FA does not include the specific tract under investigation. After accounting for modified global FA and multiple comparisons (P < 0.006), none of the individual tracts predicted a significant change in cognitive performance. FA, fractional anisotropy; ATR, anterior thalamic radiation; CB, cingulum bundle; PHC, parahippocampal cingulum; CST, coticospinal tract; IFOF, inferior frontal occipital fasciculus; ILF, inferior longitudinal fasciculus; Fma, forceps major; Fmi, forceps minor; SLF, superior longitudinal fasciculus.