For decades, neuroscientists have been conducting research in an effort to define the age that adolescence ends officially in the brain and mental adulthood is reached.

A new study published in Neuron has suggested this question may never be answered. Results from researcher Leah Somerville found that defining when a brain "reaches maturity" is much trickier than it may seem according to EurkAlert!.

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"The very idea that we could come up with some number that would encompass all of the complexity involved in brain development is a challenge. While there are decades of evidence that adolescents behave differently from adults, the age of 18 doesn't have any biological magic to it,” said Somerville, EurkAlert! reported.

Previous studies have shown that there are clear structural differences between an adolescent and adult brain. Meanwhile, research has also identified that, even by the age of 30, several regions of the brain had not yet “plateaued.”

Throughout life, the brain’s plasticity — or ability to learn new things — constantly changes.

"When considering whether an individual brain can diagnose someone as mature or immature, neuroscientists have deep concerns about trying to make those kinds of inferences," Somerville explained.

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The human brain grows fast, Medical Daily previously reported. By the age of 2, your brain is 80 percent of its adult size. But the chemical structure continues to change — just like the rest of your organs.

Source: Somerville LH. Searching for Signatures of Brain Maturity: What Are We Searching For? Neuron. 2016.

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