How is “brain age” calculated?

The brain faces many challenges throughout its life. From birth to maturity, from aging to death, the external environment often fluctuates, and the body structure is constantly changing. At the age of 6, the brain maturity of children exceeds 90%. Therefore, before the age of 6 is considered the "golden" period of brain development, which is the core stage of sensory experience and intellectual development. Brain development abnormalities caused by various genetic and environmental factors (such as autism) often accumulate and show symptoms at this age. The improvement of brain development and function in childhood is not only the cornerstone of the early development and remodeling of the human brain, but also the physiological basis for the formation of life meaning and value judgment, and the source of lifelong happiness.

For a long time, due to limitations in clinical examination methods, parent-child cooperation, and neuroimaging model construction methods, imaging studies of human brain development have mostly focused on the age group after 6 years old, which has seriously restricted people's understanding of the mechanism of the critical period of brain development and hindered the progress of early diagnosis systems for brain development diseases based on imaging technology. Therefore, the construction of a "growth curve" as a "measurement" has always been lacking in the field of brain development, making it impossible for us to accurately evaluate children's brain development status, such as "brain age" and "brain development score".

A study from the University of Pennsylvania collected more than 120,000 brain scans - the largest sample group to date - and based on this, drew the first complete brain development maps. These curves intuitively show how the human brain expands rapidly in early life and then gradually shrinks with age. The research results were published in Nature on April 6, 2022, which amazed neuroscientists who were struggling to study repetitive problems. These studies have drawn a comprehensive standardized growth curve for the brain, a vital organ in the whole body, for the first time: BrainChart.

The research results intuitively show how the human brain expands rapidly in early life and then slowly shrinks as we age. The brain map covers changes in the brain throughout life. It can not only assess whether the brain is growing and developing normally in the early stages of life, like the growth curves used by pediatricians, but also systematically assess brain aging and the impact of diseases such as Alzheimer's disease.