TY - JOUR
T1 - Fiber bundle length and cognition
T2 - a length-based tractography MRI study
AU - Behrman-Lay, Ashley M.
AU - Usher, Christina
AU - Conturo, Thomas E.
AU - Correia, Stephen
AU - Laidlaw, David H.
AU - Lane, Elizabeth M.
AU - Bolzenius, Jacob
AU - Heaps, Jodi M.
AU - Salminen, Lauren E.
AU - Baker, Laurie M.
AU - Cabeen, Ryan
AU - Akbudak, Erbil
AU - Luo, Xi
AU - Yan, Peisi
AU - Paul, Robert H.
N1 - Funding Information:
This study was supported by the following grants: NIH/NINDS grant numbers R01 NS052470 and R01 NS039538, NIH/NIMH grant number R21 MH090494. Recruitment database searches were supported in part by NIH/NCRR grant UL1 TR000448.
Publisher Copyright:
© 2014, Springer Science+Business Media New York.
PY - 2015/12/1
Y1 - 2015/12/1
N2 - Executive function (EF) and cognitive processing speed (CPS) are two cognitive performance domains that decline with advanced age. Reduced EF and CPS are known to correlate with age-related frontal-lobe volume loss. However, it remains unclear whether white matter microstructure in these regions is associated with age-related decline in EF and/or CPS. We utilized quantitative tractography metrics derived from diffusion-tensor MRI to investigate the relationship between the mean fiber bundle lengths (FBLs) projecting to different lobes, and EF/CPS performance in 73 healthy aging adults. We measured aspects of EF and CPS with the Trail Making Test (TMT), Color-Word Interference Test, Letter-Number Sequencing (L-N Seq), and Symbol Coding. Results revealed that parietal and occipital FBLs explained a significant portion of variance in EF. Frontal, temporal, and occipital FBLs explained a significant portion of variance in CPS. Shorter occipital FBLs were associated with poorer performance on the EF tests TMT-B and CWIT 3. Shorter frontal, parietal, and occipital FBLs were associated with poorer performance on L-N Seq and Symbol Coding. Shorter frontal and temporal FBLs were associated with lower performance on CPS tests TMT-A and CWIT 1. Shorter FBLs were also associated with increased age. Results suggest an age-related FBL shortening in specific brain regions related to poorer EF and CPS performance among older adults. Overall, results support both the frontal aging hypothesis and processing speed theory, suggesting that each mechanism is contributing to age-related cognitive decline.
AB - Executive function (EF) and cognitive processing speed (CPS) are two cognitive performance domains that decline with advanced age. Reduced EF and CPS are known to correlate with age-related frontal-lobe volume loss. However, it remains unclear whether white matter microstructure in these regions is associated with age-related decline in EF and/or CPS. We utilized quantitative tractography metrics derived from diffusion-tensor MRI to investigate the relationship between the mean fiber bundle lengths (FBLs) projecting to different lobes, and EF/CPS performance in 73 healthy aging adults. We measured aspects of EF and CPS with the Trail Making Test (TMT), Color-Word Interference Test, Letter-Number Sequencing (L-N Seq), and Symbol Coding. Results revealed that parietal and occipital FBLs explained a significant portion of variance in EF. Frontal, temporal, and occipital FBLs explained a significant portion of variance in CPS. Shorter occipital FBLs were associated with poorer performance on the EF tests TMT-B and CWIT 3. Shorter frontal, parietal, and occipital FBLs were associated with poorer performance on L-N Seq and Symbol Coding. Shorter frontal and temporal FBLs were associated with lower performance on CPS tests TMT-A and CWIT 1. Shorter FBLs were also associated with increased age. Results suggest an age-related FBL shortening in specific brain regions related to poorer EF and CPS performance among older adults. Overall, results support both the frontal aging hypothesis and processing speed theory, suggesting that each mechanism is contributing to age-related cognitive decline.
KW - Aging
KW - Cognitive processing speed
KW - DTI
KW - Executive function
KW - Fiber bundle lengths
KW - White matter
UR - http://www.scopus.com/inward/record.url?scp=84948568395&partnerID=8YFLogxK
U2 - 10.1007/s11682-014-9334-8
DO - 10.1007/s11682-014-9334-8
M3 - Article
C2 - 25376332
AN - SCOPUS:84948568395
SN - 1931-7557
VL - 9
SP - 765
EP - 775
JO - Brain Imaging and Behavior
JF - Brain Imaging and Behavior
IS - 4
ER -