The good news is that recent research suggests IQ is somewhat malleable in the adolescent years. At the onset of puberty, the brain moves into a neural pruning stage in which it interacts with the environment, building synapses in areas of demand while purging neurons from areas of little stimulation. Throughout adolescence, the prefrontal cortex continues to add synapses, increasing our ability to learn and our capacity for abstract thought–a transition from semi-concrete to formal operational described by psychologist Jean Piaget.
By the end of adolescence, the pruning has resulted in a decrease of between 5 and 10 percent in brain mass, but the brain has efficiently attuned itself to the environment in which it will need to function. Throughout this development, we might expect that our IQ might remain relatively stable because IQ is a measure of our intelligence relative to others of the same age. However, recent research indicates that while the average IQ of those in the same age cohort is relatively stable, the IQ of an individual can change significantly during this period. In a longitudinal study, 33 teenagers of average age 14.1 years were administered an IQ test and a structural brain scan in 2004 and then again in 2007, when their average age was 17.7 years. It was found that during this period, the average IQ of the group had changed very little; however about 20% of the participants showed a positive or negative change in IQ of at least 15 points (one standard deviation). Furthermore, magnetic resonance imaging (MRI) revealed that positive changes in IQ corresponded to increased gray matter in sections of the brain associated with the stimulated cognitive functions. (See Ramsden, Sue. et al. 2011. “Verbal and non-verbal intelligence changes in the teenage brain.” Nature. Vol. 479. pp. 113-116.) Summarizing their findings, the researchers reported:
Our results emphasize the possibility that an individual’s intellectual capacity relative to their peers can decrease or increase in the teenage years. This would be encouraging to those whose intellectual potential may improve, and would be a warning that early achievers may not maintain their potential.
It is vitally important during the adolescent years to continue to stimulate the brain as much as possible and to get lots of sleep to enable the brain to restructure itself during your slumber.
