Research identifies changes in neural circuits underlying self-control during adolescence

Research identifies changes in neural circuits underlying self-control during adolescence

Study shows developing brain networks support cognition in youth

January 3, 2020

Science Daily/University of Pennsylvania School of Medicine

Researchers applied tools from network science to identify how anatomical connections in the brain develop to support neural activity underlying executive function.

The human brain is organized into circuits that develop from childhood through adulthood to support executive function -- critical behaviors like self-control, decision making, and complex thought. These circuits are anchored by white matter pathways which coordinate the brain activity necessary for cognition. However, little research exists to explain how white matter matures to support activity that allows for improved executive function during adolescence -- a period of rapid brain development.

Researchers from the Lifespan Brain Institute of the Perelman School of Medicine at the University of Pennsylvania and Children's Hospital of Philadelphia applied tools from network science to identify how anatomical connections in the brain develop to support neural activity underlying these key areas. The findings were published in the Proceedings of the National Academy of Sciences.

"By charting brain development across childhood and adolescence, we can better understand how the brain supports executive function and self-control in both healthy kids and those with different mental health experiences," said the study's senior author Theodore Satterthwaite, MD, an assistant professor of Psychiatry at Penn. "Since abnormalities in developing brain connectivity and deficits in executive function are often linked to the emergence of mental illness during youth, our findings may help identify biomarkers of brain development that predict cognitive and clinical outcomes later in life."

In this study, the researchers mapped structure-function coupling -- the degree to which a brain region's pattern of anatomical connections supports synchronized neural activity. This could be thought of like a highway, where the anatomical connections are the road and the functional connections are the traffic flowing along those roads. Researchers mapped and analyzed multi-modal neuroimaging data from 727 participants ages 8 to 23 years, and three major findings emerged.

First, the team found that regional variability in structure-function coupling was inversely related to the complexity of the function a given brain area is responsible for. Higher structure-function coupling was found in parts of the brain that are specialized for processing simple sensory information, like the visual system. In contrast, there was lower structure-function coupling in complex parts of the brain that are responsible for executive function and self-control, which require more abstract and flexible processing.

Results showed that structure-function coupling also aligned with known patterns of brain expansion over the course of primate evolution. Previous work comparing human, ape, and monkey brains has showed that sensory areas like the visual system are highly conserved across primate species and have not expanded much during recent evolution. In contrast, association areas of the brain, such as the prefrontal cortex, have expanded dramatically over the course of primate evolution. This expansion may have allowed for the emergence of uniquely complex human cognitive abilities. The team found that the brain areas which expanded rapidly during evolution had lower structure-function coupling, while simple sensory areas that have been conserved in recent evolution had higher structure-function coupling.

Researchers also found that structure-function coupling increased throughout childhood and adolescence in complex frontal brain regions. These are the same regions that tend to have lower baseline structure-function coupling, are expanded compared to monkeys, and are responsible for self-control. The prolonged development of structure-function coupling in these regions may allow for improved executive function and self-control that develops into adulthood. Indeed, the team found that higher structure-function coupling in the lateral prefrontal cortex -- a complex brain area which plays important roles in self-control -- was associated with better executive function.

"These results suggest that executive functions like impulse control -- which can be particularly challenging for children and adolescents -- rely in part on the prolonged development of structure-function coupling in complex brain areas like the prefrontal cortex," explained lead author Graham Baum, PhD, a postdoctoral fellow at Harvard University, who was a Penn neuroscience PhD student during the time of the research. "This has important implications for understanding how brain circuits become specialized during development to support flexible and appropriate goal-oriented behavior."

https://www.sciencedaily.com/releases/2020/01/200103111723.htm

Emphasizing social play in kindergarten improves academics, reduces teacher burnout

September 17, 2019

Science Daily/University of British Columbia

Emphasizing more play, hands-on learning, and students helping one another in kindergarten improves academic outcomes, self-control and attention regulation, finds new UBC research.

The study, published today in the journal PLoS One, found this approach to kindergarten curriculum also enhanced children's joy in learning and teachers' enjoyment of teaching, and reduced bullying, peer ostracism, and teacher burnout.

"Before children have the ability to sit for long periods absorbing information the way it is traditionally presented in school through lectures, they need to be allowed to be active and encouraged to learn by doing," said Dr. Adele Diamond, the study's lead author, a professor in the UBC Department of Psychiatry and Canada Research Chair in Developmental Cognitive Neuroscience. "Indeed, people of all ages learn better by doing than by being told."

Through a randomized controlled trial, Diamond and her colleagues analyzed the effectiveness of a curriculum called Tools of the Mind (Tools). The curriculum was introduced to willing kindergarten teachers and 351 children with diverse socio-economic backgrounds in 18 public schools across the school districts of Vancouver and Surrey.

Tools was developed in 1993 by American researchers Drs. Elena Bodrova and Deborah Leong. Its foundational principle is that social-emotional development and improving self-control is as important as teaching academic skills and content. The program emphasizes the role of social dramatic play in building executive functions -- which includes skills such as self-control and selective attention, working memory, cognitive flexibility, reasoning, and planning.

"Executive functioning skills are necessary for learning, and are often more strongly associated with school readiness than intelligence quotient (IQ)," said Diamond. "This trial is the first to show benefits of a curriculum emphasizing social play to executive functioning in a real-world setting."

Previous studies had demonstrated that Tools produces better results for reading and math and on laboratory tests of executive functions. Diamond's new study demonstrates for the first time that Tools also dramatically improves writing (exceeding the top level on the provincial assessment scale), improves executive functions in the real world, and has a host of social and emotional benefits not previously documented.

Teachers reported more helping behavior and greater sense of community in Tools classes. Cliques developed in most control classes, but in few Tools classes. Late in the school year, Tools teachers reported still feeling energized and excited about teaching, while control teachers were exhausted.

"I have enjoyed seeing the enormous progress my students have made in writing and reading. I have never had so many students writing two or three sentences by the end of kindergarten," said Susan Kochan, a Tools teacher in Vancouver. "I have also enjoyed seeing the students get so excited about coming to school and learning. They loved all the activities we did so much that many students didn't want to miss school, even if they were sick."

https://www.sciencedaily.com/releases/2019/09/190917140317.htm

Exercise may improve thinking skills in people as young as 20

January 30, 2019

Science Daily/American Academy of Neurology

Regular aerobic exercise such as walking, cycling or climbing stairs may improve thinking skills not only in older people but in young people as well, according to a new study. The study also found that the positive effect of exercise on thinking skills may increase as people age.

The specific set of thinking skills that improved with exercise is called executive function. Executive function is a person's ability to regulate their own behavior, pay attention, organize and achieve goals.

"As people age, there can be a decline in thinking skills, however our study shows that getting regular exercise may help slow or even prevent such decline," said study author Yaakov Stern, PhD, of Columbia University in New York, and a member of the American Academy of Neurology. "We found that all participants who exercised not only showed improvements in executive function but also increased the thickness in an area of the outer layer of their brain."

The study involved 132 people between the ages of 20 and 67 who did not smoke or have dementia but who also did not exercise at the start of the study and were determined to have below average fitness levels. Participants were randomly assigned to six months of either aerobic exercise or stretching and toning four times a week. The two groups were equally balanced for age, sex, education as well as memory and thinking skills at the start of the study.

All participants either exercised or stretched and toned at a fitness center and checked in weekly with coaches monitoring their progress. They all wore heart rate monitors as well. Participants' thinking and memory skills were evaluated at the start of the study as well as at three months and at the end of the six-month study.

Participants in the exercise group chose from aerobic activities including walking on a treadmill, cycling on a stationary bike or using an elliptical machine. They ramped up their activity during the first month, then during the remainder of the six-month study they trained at 75 percent of their maximum heart rate. People in the stretching and toning group did exercises to promote flexibility and core strength.

Researchers measured participants' aerobic capacity using a cycling machine called an ergometer that estimates exercise intensity. Participants also had MRI brain scans at the start and end of the study.

Researchers found that aerobic exercise increased thinking skills. From the beginning of the study to the end, those who did aerobic exercise improved their overall scores on executive function tests by 0.50 points, which was a statistically significant difference from those who did stretching and toning, who improved by 0.25 points. At age 40, the improvement in thinking skills was 0.228 standard deviation units higher in those who exercised compared to those who did stretching and toning and at age 60, it was 0.596 standard deviation units higher.

"Since a difference of 0.5 standard deviations is equivalent to 20 years of age-related difference in performance on these tests, the people who exercised were testing as if they were about 10 years younger at age 40 and about 20 years younger at age 60," Stern said.

He added, "Since thinking skills at the start of the study were poorer for participants who were older, our findings suggest that aerobic exercise is more likely to improve age-related declines in thinking skills rather than improve performance in those without a decline."

Researchers also found an increase in the thickness of the outer layer of the brain in the left frontal area in all those who exercised, suggesting that aerobic exercise contributes to brain fitness at all ages.

"Our research confirms that exercise can be beneficial to adults of any age," said Stern.

Overall, researchers did not find a link between exercise and improved memory skills. However, those with the genetic marker for dementia, the APOE ?4 allele, showed less improvement in thinking skills.

A limitation of the study is the small number of participants. Larger studies over longer periods of time may allow researchers to see other effects in thinking and memory skills.

The study was supported by the National Institutes of Health.

https://www.sciencedaily.com/releases/2019/01/190130161638.htm

Exercise may improve thinking skills in people as young as 20

January 30, 2019

Science Daily/American Academy of Neurology

Regular aerobic exercise such as walking, cycling or climbing stairs may improve thinking skills not only in older people but in young people as well, according to a new study. The study also found that the positive effect of exercise on thinking skills may increase as people age.

The specific set of thinking skills that improved with exercise is called executive function. Executive function is a person's ability to regulate their own behavior, pay attention, organize and achieve goals.

"As people age, there can be a decline in thinking skills, however our study shows that getting regular exercise may help slow or even prevent such decline," said study author Yaakov Stern, PhD, of Columbia University in New York, and a member of the American Academy of Neurology. "We found that all participants who exercised not only showed improvements in executive function but also increased the thickness in an area of the outer layer of their brain."

The study involved 132 people between the ages of 20 and 67 who did not smoke or have dementia but who also did not exercise at the start of the study and were determined to have below average fitness levels. Participants were randomly assigned to six months of either aerobic exercise or stretching and toning four times a week. The two groups were equally balanced for age, sex, education as well as memory and thinking skills at the start of the study.

All participants either exercised or stretched and toned at a fitness center and checked in weekly with coaches monitoring their progress. They all wore heart rate monitors as well. Participants' thinking and memory skills were evaluated at the start of the study as well as at three months and at the end of the six-month study.

Participants in the exercise group chose from aerobic activities including walking on a treadmill, cycling on a stationary bike or using an elliptical machine. They ramped up their activity during the first month, then during the remainder of the six-month study they trained at 75 percent of their maximum heart rate. People in the stretching and toning group did exercises to promote flexibility and core strength.

Researchers measured participants' aerobic capacity using a cycling machine called an ergometer that estimates exercise intensity. Participants also had MRI brain scans at the start and end of the study.

Researchers found that aerobic exercise increased thinking skills. From the beginning of the study to the end, those who did aerobic exercise improved their overall scores on executive function tests by 0.50 points, which was a statistically significant difference from those who did stretching and toning, who improved by 0.25 points. At age 40, the improvement in thinking skills was 0.228 standard deviation units higher in those who exercised compared to those who did stretching and toning and at age 60, it was 0.596 standard deviation units higher.

"Since a difference of 0.5 standard deviations is equivalent to 20 years of age-related difference in performance on these tests, the people who exercised were testing as if they were about 10 years younger at age 40 and about 20 years younger at age 60," Stern said.

He added, "Since thinking skills at the start of the study were poorer for participants who were older, our findings suggest that aerobic exercise is more likely to improve age-related declines in thinking skills rather than improve performance in those without a decline."

Researchers also found an increase in the thickness of the outer layer of the brain in the left frontal area in all those who exercised, suggesting that aerobic exercise contributes to brain fitness at all ages.

"Our research confirms that exercise can be beneficial to adults of any age," said Stern.

Overall, researchers did not find a link between exercise and improved memory skills. However, those with the genetic marker for dementia, the APOE ?4 allele, showed less improvement in thinking skills.

A limitation of the study is the small number of participants. Larger studies over longer periods of time may allow researchers to see other effects in thinking and memory skills.

The study was supported by the National Institutes of Health.

https://www.sciencedaily.com/releases/2019/01/190130161638.htm

ADHD kids can be still, if they're not straining their brains

ADHD symptoms manifest watching videos requiring executive brain function

September 18, 2017

Science Daily/University of Central Florida

Lack of motivation or boredom with school isn't to blame for squirming by children with Attention Deficit Hyperactivity Disorder. Symptoms such as fidgeting, foot-tapping and chair-swiveling are triggered by cognitively demanding tasks - like school and homework. But movies and video games don't typically require brain strain, so the excessive movement doesn't manifest.

How's this for exasperating: Your ADHD child fidgets and squirms his way through school and homework, but seems laser-focused and motionless sitting in front of the TV watching an action thriller.

Well, fret not, because new research shows lack of motivation or boredom with school isn't to blame for the differing behavior. It turns out that symptoms of Attention Deficit Hyperactivity Disorder such as fidgeting, foot-tapping and chair-swiveling are triggered by cognitively demanding tasks -- like school and homework. But movies and video games don't typically require brain strain, so the excessive movement doesn't manifest.

"When a parent or a teacher sees a child who can sit perfectly still in one condition and yet over here they're all over the place, the first thing they say is, 'Well, they could sit still if they wanted to,'" said Mark Rapport, director of the Children's Learning Clinic at the University of Central Florida. "But kids with ADHD only need to move when they are accessing their brain's executive functions. That movement helps them maintain alertness."

Scientists once thought that ADHD symptoms were always present. But previous research from Rapport, who has been studying ADHD for more than 36 years, has shown the fidgeting was most often present when children were using their brains' executive functions, particularly "working memory." That's the system we use for temporarily storing and managing information required to carry out complex cognitive tasks such as learning, reasoning and comprehension.

As recently published in the Journal of Abnormal Child Psychology, Professor Rapport's senior doctoral student Sarah Orban and research team tested 62 boys ages 8 to 12. Of those, 32 had ADHD. Thirty did not have ADHD and acted as a control group.

During separate sessions, the children watched two short videos, each about 10 minutes long. One was a scene from "Star Wars Episode I -- The Phantom Menace" in which a young Anakin Skywalker competes in a dramatic pod-race. The other was an instructional video featuring an instructor verbally and visually presenting multistep solutions to addition, subtraction and multiplication problems.

While watching, the participants were observed by a researcher, recorded and outfitted with wearable actigraphs that tracked their slightest movements. The children with ADHD were largely motionless while watching the Start Wars clip, but during the math video they swiveled in their chairs, frequently changed positions and tapped their feet.

That may not seem surprising. After all, weren't the children absorbed by the sci-fi movie and bored by the math lesson? Not so, Rapport said.

"That's just using the outcome to explain the cause," he said. "We have shown that what's really going on is that it depends on the cognitive demands of the task. With the action movie, there's no thinking involved -- you're just viewing it, using your senses. You don't have to hold anything in your brain and analyze it. With the math video, they are using their working memory, and in that condition movement helps them to be more focused."

The takeaway: Parents and teachers of children with ADHD should avoid labeling them as unmotivated slackers when they're working on tasks that require working memory and cognitive processing, researchers said.

The study builds on Rapport's earlier research, including a 2015 study that found that children with ADHD must be allowed to squirm to learn.

Video: https://www.youtube.com/watch?v=167se17RNHw

https://www.sciencedaily.com/releases/2017/09/170918222249.htm