Researchers from Melbourne's Monash University looked at the long-held belief that the brain's activity patterns are caused by a complex web of neural connections.
Their study, published on Thursday in the international journal Nature, found that wasn't necessarily the case.
"It turns out that activity moves through the brain like a travelling wave of water," research professor Alex Fornito told AAP.
"If you imagine a raindrop falling into a pond, it will send ripple patterns that fan out and the shape of the pond will influence the pattern of ripples you see.
"Much in the same way, the shape of the brain constrains the way in which waves of activity propagate throughout the brain, and in turn, influence the patterns of activity."
More than 10,000 brain maps, taken by MRI while people were performing different tasks, were analysed in the Monash-led study.
The researchers used the maps to look at the eigenmodes - or the natural patterns of vibration in the brain.
"The eigenmodes of the brain influence the patterns of activity," Professor Fornito said.
"We found it was the eigenmodes of the shape of the brain that were more important for understanding function than the eigenmodes of connectivity."
This study is the first to establish a link between brain shape and activity but it could lead to changes in the way diseases are diagnosed or behaviour is predicted, Prof Fornito said.
"Since everyone's brain shape is different, much like a fingerprint, it's possible that differences in brain shape are related to differences in the way we think and behave in the world," he said.
"If we can understand the early development of brain shape, it could shed light on the mechanisms of risk for mental illnesses and neurological disorders like schizophrenia, depression and dementia."
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