Researchers at UCLA and the National Institute of Mental Health recorded images of the brains of 13 children who were scanned every two years for eight years. The researchers found a consistent pattern of development.

The areas that control basic functions such as movement formed neural connections at an early age, followed by the areas that control language and speech. Not until the late teens does the brain fully develop areas of judgment and impulse control.

The research did not focus on criminal behavior, but opponents of life without parole for serious juvenile offenders point to this research as evidence that juveniles may lack the capacity to make decisions in the same way adults do and should not be sentenced like adults.

For a time-lapse movie showing the brain's development, see below.

Areas in red and yellow indicate parts of the brain that are not fully developed. Areas in blue and green are more developed. Contrary to the popular use of the phrase, "gray matter" refers to brain tissue that has not yet fully developed neural connections.

Time-Lapse Imaging Tracks Brain Maturation Ages 5 to 20

Constructed from MRI scans of healthy children, these time-lapse "movies" compress 15 years of brain development (ages 5-20) into just a few seconds. Red indicates more gray matter, blue less gray matter. Gray matter wanes in a back to front wave as the brain matures and neural connections are pruned. Areas performing more basic functions mature earlier; areas for higher-order functions (emotion, self-control) mature later. The pre-frontal cortex, which handles reasoning and other "executive" functions, emerged late in evolution, and is among the last to mature.

Right oblique movie



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Left oblique movie



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Top movie



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Bottom movie



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Animated graphics

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