Tween brain researchers were surprised by the dramatic changes in brain organization when they studied normal tweens at age 9, and then 2 years later (11). When they followed the same kids, they found a dramatic reduction in bilateral prefrontal activation (blue), and increased focal activation in the R inferior frontal gyrus. The task involved responding to a specific target and ignoring a non-target distractor.
Behaviorally, this could mean quite an upheaval as systems reorganize - with the end goal of becoming more efficient. The study showed how early fMRI science is in understanding normal brain development. The changes were only seen when the same children were followed 2 years later - not when different groups of children were studied at ages 9 and 11.
Brain Reorganization of Tweens
Brain Development During Puberty