Cortical thinning is a part of normal ageing. Recent studies suggest that accelerated cortical thinning in vulnerable regions may be a useful biomarker for neuropathologies including Alzheimer’s disease (AD). Longitudinal studies, which have largely focused on older adults, have provided estimates of normative rates and patterns of age-related cortical thinning. Very little, however, is known about healthy cortical thinning at midlife. Here we provide longitudinal estimates of age-related cortical thinning observed over 8Â years, in a large (nÂ =Â 404) group of healthy individuals aged 44–49Â years at baseline, who were scanned with MRI (1.5T) on up to three occasions. Age-related cortical thinning was assessed across the whole cortex. We measured a mean annual decrease in cortical thickness of 0.26Â % on the left and 0.17Â % on the right hemisphere, and largely affecting frontal and cingulate cortices. Medial and lateral temporal regions were generally spared. Studying regions that are specifically vulnerable to—or spared from—healthy age-related cortical thinning at midlife may be important for the early identification of neurodegeneration, including AD.
- Cortical thickness