Using more than 123,000 MRI scans from over 101,000 humans – from a 16.5-week fetus to 100 year olds – scientists have mapped how our brain changes throughout our life
6 April 2022
A map of how our brain changes throughout our life could aid the diagnosis of neurological conditions.
“It’s the first time that anyone sort of stitched together these developmental patterns really, throughout the whole lifespan, going from even pre-birth to old age,” says Richard Bethlehem at the University of Cambridge.
Bethlehem and his colleagues analysed 123,984 MRI scans from 101,457 humans, from a 16.5-week fetus to 100 year olds, from more than 100 studies.
“We just asked the simple questions about how big the brain is or what is the [variation] in possible brain size across humans – actually those things haven’t really been that well addressed [in previous studies],” says team member Jakob Seidlitz at the Children’s Hospital of Philadelphia.
Among the participants, brain size increased from 10 per cent to 80 per cent of its maximum volume from about 4 months old to 3 years old, peaking at 1066 cubic centimetres at around 11 years old, before gradually declining.
The average thickness of the cortex, the brain’s outer region, peaked at 1.7 years old. Cortex thinning has been linked with neurological conditions such as Alzheimer’s disease, suggesting early brain development may influence a person’s risk of the condition in later life.
“If there are effects of this feature later in life as a function of disease, and [cortical thickness] peaks really early, then that poses the interesting question of should we be studying what leads to these diseases starting from really early on?” says Seidlitz.
The brain map could one day act as a reference for standard brain growth, similar to paediatric growth charts, helping clinicians and researchers better track the onset of neurological conditions.
“I am excited to learn about this colossal first step towards generating brain development charts that will in the future facilitate more accurate and early diagnosis of atypical developmental patterns [and neurodegenerative conditions],” says Vaidehi Natu at Stanford University in California.
In the meantime, the brain scans of a more diverse population need be studied. “What we have in our study is a majority of North American, European ancestry, city based, relatively well-off individuals that tend to take part in these research studies,” says Bethlehem. “Expanding that to have a more representative nature would make it more clinically relevant.”
Journal reference: Nature, DOI: 10.1038/s41586-022-04554-y
More on these topics: