Verbal and Non-Verbal Intelligence Changes in the Teenage Brain
An individual’s capacity to learn is often treated as static across his or her lifetime. Studies that identify changes in IQ (a widely used, standardized measure of intellectual abilities) are generally unable to attribute that change to a real increase or decrease in intelligence as opposed to measurement error in testing, and much of the variation in IQ remains unexplained.
A 2011 study in the international weekly journal of science Nature, “Verbal and Non-Verbal Intelligence Changes in the Teenage Brain,” investigates whether structural changes in the brain and longitudinal changes in IQ are related. The scientists studied 33 healthy and neurologically normal adolescents with a wide range of abilities, first testing them in 2004 at ages 12 to 16, then again in 2007/2008 at ages 15 to 20.
Key findings from the study include:
- Verbal and non-verbal (performance) IQ can rise or fall in the teenage years, and these fluctuations are correlated with structural changes in gray matter in the areas of the brain associated with speech and finger movements, respectively. These structural changes suggest that IQ fluctuations are not solely due to measurement error.
- In a composite measure of verbal and performance IQ, one-third of participants experienced a clear change in measured intelligence, with the largest gain being 21 points and the largest decrease 18 points.
- Gray matter changes associated with verbal and performance IQ do not correspond to the region of the brain associated with general intelligence (the g factor), indicating that general intelligence may remain relatively constant while verbal and performance IQ fluctuate due to changes in sensorimotor skills.
These findings may “be encouraging to those whose intellectual potential may improve, and … a warning that early achievers may not maintain their potential.” In either case, the study suggests it would be unwise to treat teenagers as if their intelligence is preordained by their IQ scores. It is still unknown if this brain plasticity extends into adulthood, and further research is needed to determine the causes of these fluctuations and their effects on educational performance and employment prospects.
In related research, scholars in Norway produced similar findings in their 2011 study, “Schooling in Adolescence Raises IQ Scores.” They found that increasing the number of years of compulsory schooling for students had a “substantial effect on IQ scores measured” at age 19.
Tags: children, youth, cognition
Note to instructor: The suggested assignments are designed for flexibility. They can be used in whole or part and can be adapted to a particular task -- for example, the newswriting assignments could be applied to the writing of the headline, the lead, the nut graph or the full story. Material from the assignments could also be combined with other material, for example, in the writing of a background, feature or local-angle story.
Read the study titled "Verbal and Non-Verbal Intelligence Changes in the Teenage Brain."
- Summarize the study in fewer than 40 words.
- Express the study's key term(s) in language a lay audience can understand.
- Evaluate the study's limitations. (For example: Do the results conflict with those of other reliable studies? Are there weaknesses in the study's data or research design?)
Read the study-related Guardian article titled "Teenagers' IQ Scores Can Rise or Fall Sharply During Adolescence."
- Reporter's use of the study: Evaluate what the reporter chose to include and exclude from the study. Would the audience have acquired a clear understanding of the study's findings and limits from this article?
- Reporter's use of other material: Assess the material in the article that is not derived from the study. For example, does the reporter place the study in the context of other research and to what effect? Does the reporter include reactions to the study from other researchers or interested parties (e.g., political groups business leaders, or community members) and are their credentials or possible biases made clear?
- Write a lead (or headline or nut graph) based on the study.
- Spend 60 minutes exploring the issue by accessing sources of information other than the study. Write a lead (or headline or nut graph) based on the study but informed by the new information. Does the new information significantly change what one would write based on the study alone?
- Interview two sources with a stake in or knowledge of the issue. Be prepared to provide them with a short summary of the study in order to get their response to it. Write a 400-word article about the study incorporating material from the interviews.
- Spend additional time exploring the issue and then write a 1,200-word background article, focusing on major aspects of the issue.