August 13th, 2026
There are now scores of aging clocks in the literature, most of which have come and gone and see little adoption. Most research is focused on gathering more data for handful of mainstream clocks, but these clocks are intended to capture a measure of aging generally across the whole body, keyed to outcomes such as mortality risk. Evidence suggests that different organs and tissues can age at different rates, however. Thus there remains a need for the development and validation of tissue-specific aging clocks. Here, researchers review the present state of development for clocks intended to measure aging in the brain specifically.
Brain aging represents a critical risk factor for neurodegenerative diseases and cognitive decline, yet the measurement of biological brain age remains challenging. Brain aging clocks, which quantify the discrepancy between predicted brain age and chronological age, have emerged as powerful tools for assessing brain health and predicting disease outcomes. Recent advances have transformed these clocks from simple global metrics to sophisticated, multi-modal approaches that capture regional heterogeneity, measure the pace of aging, and achieve cellular resolution.
