Variation in longitudinal trajectories of regional brain volumes of healthy men and women (ages 10 to 85years) measured with atlas-based parcellation of MRI

Abstract

Numerous cross-sectional MRI studies have characterized age-related differences in regional brain volumes that differ with structure and tissue type. The extent to which cross-sectional assumptions about change are accurate depictions of actual longitudinal measurement remains controversial. Even longitudinal studies can be limited by the age range of participants, sex distribution of the samples, and scan intervals. To address these issues, we calculated trajectories of regional brain volume changes from T1-weighted (SPGR) MRI data, quantified with our automated, unsupervised SRI24 atlas-based registration and parcellation method. Longitudinal MRIs were acquired at 3T in 17 boys and 12 girls, age 10 to 14 years, and 41 men and 41 women, age 20 to 85 years at first scan. Application of a regression-based correction factor permitted merging of data acquired at 3T field strength with data acquired at 1.5T from additional subjects, thereby expanding the sample to a total of 55 men and 67 women, ages 20 to 85 years at first scan. Adjustment for individual supratentorial intracranial volume removed regional volume differences between men and women due to sex-related differences in head size. Individual trajectories were computed from data collected on 2 to 6 MRIs at a single field strength over a ~1 to 8 year interval. Using the linear mixed-effects model, the pattern of trajectories over age indicated: rises in ventricular and Sylvian fissure volumes, with older individuals showing faster increases than younger ones; declines in selective cortical volumes with faster tissue shrinkage in older than younger individuals; little effect of aging on volume of the corpus callosum; more rapid expansion of CSF-filled spaces in men than women after age 60 years; and evidence for continued growth in central white matter through early adulthood with accelerated decline in senescence greater in men than women.

Normative data for subcortical regional volumes over the lifetime of the adult human brain

“…Similar results were previously observed (Fjell et al, 2009;Fjell et al, 2013;Goodro et al, 2012;Pfefferbaum et al, 2013;Walhovd et al, 2011). Goodro and colleagues suggested that periventricular white matter signal hyperintensities, which is highly correlated with age, could be responsible for this increase of caudate volume, from the age of 60 onward.…”

“…Indeed, although many studies have described the influence of age and sex on brain volumes (Fjell et al, 2013;Luders et al, 2009;Pfefferbaum et al, 2013;Walhovd et al, 2011), very few attempts have been made to produce proper neuroanatomical volumetric normative data (Brain Development Cooperative Group, 2012;Kruggel, 2006). The many obstacles inherent to neuroimaging research likely undermine this shortcoming.…”

Monkeys that Voluntarily and Chronically Drink Alcohol Damage their Brains: a Longitudinal MRI Study

“…Age is an additional factor that leads to brain tissue volume decline in humans (Pfefferbaum et al, 1994;Pfefferbaum et al, 2013;Raz et al, 2010;Raz et al, 2005). The animals studied here ranged in age from 5.5 to 9.6 years at the beginning of the induction period, with a mean ± SD of 7.2 ± 1.6 years.…”

Structure and function of the aging brain

“…On balance, existing research is consistent with these hypotheses, with frontal and heteromodal association areas most commonly identified as undergoing more rapid decline than sensory-motor regions [16,19,21,25,39]. This leads directly to the conclusion that accelerated volume loss is not simply a global feature of structural brain aging.…”

“…Finally, while a full review of sex differences in age-related brain change is beyond the scope of this review, it is important to note that the majority of published reports (whether cross-sectional or longitudinal) and across both global and regional measures, show a steeper and more rapid trajectory of decline for males than females [e.g. 3,19,20,24,[25][26][27] Regional changes. The earliest in vivo imaging studies reported global, or non-specific, brain changes in late life [28].…”