Developmental trajectories of cerebral blood flow and oxidative metabolism at baseline and during working memory tasks.
The neurobiological interpretation of developmental BOLD fMRI findings remains difficult due to the confounding issues of potentially varied baseline of brain function and varied strength of neurovascular coupling across age groups. The central theme of the present research is to study the development of brain function and neuronal activity through in vivo assessments of cerebral blood flow (CBF), oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) both at baseline and during the performance of a working memory task in a cohort of typically developing children aged 7 to 18years. Using a suite of 4 emerging MRI technologies including MR blood oximetry, phase-contrast MRI, pseudo-continuous arterial spin labeling (pCASL) perfusion MRI and concurrent CBF/BOLD fMRI, we found: 1) At baseline, both global CBF and CMRO2 showed an age related decline while global OEF was stable across the age group; 2) During the working memory task, neither BOLD nor CBF responses showed significant variations with age in the activated fronto-parietal brain regions. Nevertheless, detailed voxel-wise analyses revealed sub-regions within the activated fronto-parietal regions that show significant decline of fractional CMRO2 responses with age. These findings suggest that the brain may become more "energy efficient" with age during development.
Laboratory of FMRI Technology (LOFT), Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA.
Mayank A
MA
Jog
Laboratory of FMRI Technology (LOFT), Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA.
Lirong
L
Yan
Laboratory of FMRI Technology (LOFT), Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA.
Emily
E
Kilroy
Laboratory of FMRI Technology (LOFT), Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA.
Kate
K
Krasileva
Laboratory of FMRI Technology (LOFT), Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA.
Kay
K
Jann
Department of Medicine Statistics Core, UCLA, Los Angeles, CA, USA.
Holly
H
LeClair
Department of Medicine Statistics Core, UCLA, Los Angeles, CA, USA.
David
D
Elashoff
Laboratory of FMRI Technology (LOFT), Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA. Electronic address: jwang71@gmail.com.
Danny J J
DJJ
Wang
D000293:Adolescent; D001921:Brain / Q000098:blood supply* / Q000254:growth & development* / Q000378:metabolism; D001931:Brain Mapping / Q000379:methods; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010092:Oximetry; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D013113:Spin Labels
D013113:Spin Labels; D010100:Oxygen
Cerebral blood flow (CBF); Cerebral metabolic rate of oxygen consumption (CMRO(2)); Developmental fMRI; Neurovascular coupling; Working memory