Childhood Development: ADHD and Problem Behavior

Two new studies were recently published that shed light on several aspects of childhood behavioral development. The first has to do with how the brains of children with Attention Deficit / Hyperactivity Disorder (ADHD) develop differently from those of normal children. The second study, entitled "School Readiness and Later Achievement," assessed the power of early childhood social and academic skills to predict later math and reading achievement. I choose to discuss both of these studies because they are related in that they both examine aspects of childhood behavior that is often deemed unacceptable and in need of treatment. In the former case of ADHD, this treatment is often pharmaceutical. I learned about this new research from an article in the New York Times entitled “Bad Behavior Does Not Doom Pupils, Studies Say.” Although I think this headline might be a little too optimistic, both studies should be at least slightly encouraging to parents.

The ADHD brain development study involved 446 children, half of whom had been diagnosed with ADHD. Each of the children’s brains was scanned using MRI two or more times at about three year intervals between their early preschool years and young adulthood. The researchers examined the images of the brains to ascertain the thickness of over 40,000 cortex sites. Childhood brain development follows a pattern first of cortex thickening and later thinning when unused neurons are pruned away. They found that half of the cortex sites gained peak thickness about three years later, at about 10.5 years of age in the group with ADHD versus 7.5 in the control group (see picture on left). Nevertheless, the brains of children in both groups followed the same general developmental pattern. The brain’s frontal cortex was one of the areas where the children with ADHD showed the most delay in development. This area is thought to be responsible for many behaviors that are disturbed in people with ADHD, such as controlling impulses, focusing attention, and organizing complex tasks. Notably, one area of the brain, the motor cortex, actually matured faster in the children with ADHD which may explain the fidgetiness and excessive movement that sometimes characterize the hyperactive form of the disorder.

The second study set out to analyze which characteristics of preschool children would best predict their “later teacher ratings and test scores of reading and math achievement.” Among the early traits of preschool students, they found that school-entry math skills best predicted later reading and math performance, followed by early language and reading skills, and then attention skills. The most surprising result of the study was that there was no correlation between early “problem behaviors and social skills” and later math and reading achievement (see image at right). According to the New York Times article, “educators and psychologists have long feared that children entering school with behavior problems were doomed to fall behind in the upper grades.” Fundamentally, what the study says is that children who enter school being good at math and reading tend to continue to be good at math and reading regardless of whether or not they have poor social skills or act out. Put this way, the result does not seem as surprising. However, the researchers did attempt to control for the preschoolers’ cognitive ability, although they admitted that “despite our ability to control for cognitive ability … and despite our controls for concurrent reading skills in all six studies, it remains possible that our surprisingly large school-entry math coefficients overstate causal impacts.” Simply stated, the correlation between early math performance and later math and reading performance may just be the result of smart children being more likely to have early math skills than their less intellectually gifted peers. Nonetheless, just because early behavior and social skills don’t correlate with later academic achievement doesn’t mean nothing should be done to correct problem behavior, as being able to do math is of little use if a person is unable to interact with others.

Both of these studies should at the very least offer comfort to parents that are worried that any psychological or behavior problems their young children may have now will have a detrimental effect on their children’s lives forever. The ADHD brain imaging study shows that the brains of children who are diagnosed with ADHD at a young age develop in essentially the same pattern as those of normal children just a little bit later. Although it’s too early to tell, perhaps this new information will ease the pressure on parents to medicate their young children for ADHD if in many cases the disorder will go away on its own with a little patience. ADHD such as methylphenidate and amphetamine can help in some cases, but they have also been known to have serious side effects such as appetite suppression which in turn may cause stunted growth in young children. As for the second study, while it is very limited in scope, it may reassure some parents dealing with unruly children that the unruly behavior is at least an isolated problem and most likely will not affect academic performance.

Brain Surgery in the Blogosphere

This week, instead of doing a regular post, I decided to explore the blogosphere. I found two posts on something many of us may not be familiar with: brain surgery. The idea of directly manipulating the brain may cause us to think of old-fashioned lobotomies, like the one preformed on the main character in One Flew Over the Cuckoo’s Nest, which rendered him mostly incapacitated. A lobotomy of this sort usually involved direct manipulation of the prefrontal cortex, either severing connections to it or removing it all together. The prefrontal cortex is thought to be the brain’s executive control center, responsible for organizing one’s thoughts and planning behavior. Lobotomies of this sort are not preformed today, at least in the United States. However, the first post I commented on was one on the blog Furious Seasons about modern-day “lobotomies” being preformed in China [as seen in the picture at right]. The second post I commented on was on the Wall Street Journal’s health blog and is about deep brain stimulation [picture below left] as a treatment for Tourette syndrome.

My Comment on "Lobotomies In China":

First of all, as an avid reader of your blog, I would like to thank you for calling attention to this important development in China. It seems to me that these brain surgeries are being preformed with little oversight and without any hard scientific evidence that they are effective. The story of the Mr. Mi in particular, is heart wrenching because of the fact that the damage to his brain is so totally irreversible. However, I am wondering if it may be a mistake to label these surgeries as lobotomies, since even the Wall Street Journal acknowledges that the “areas of the brain being targeted are more precise.” Also, isn’t the term “lobotomy” usually used in reference to manipulation of the prefrontal cortex in particular? Do we have any idea if this is also the area that Chinese surgeons are targeting? It is also interesting that Dr. Wang says “93% of respondents [to the surgery] had shown improvement.” If this figure is true, then the Wall Street Journal probably could have found one family to interview whose life had been improved by the surgery. Nevertheless, if there really are people who have improved because of this surgery, they may not have felt the need to risk getting in trouble with the government by talking to foreign reporters. Although the fact that these surgeries are so prevalent in China does at first lead me to think they are a clear-cut case of medical malpractice, it does not seem wise to me to draw conclusions about all of the patients from two interviews. Unfortunately it may not be possible in China, but I would like to see more research done on the outcomes of these surgeries before drawing conclusions.

My Comment on "Brain Stimulation Helps Tourette’s Patients":

First I would like to say thank you for posting on this new development in the treatment of Tourette syndrome. From my limited experience with people who have the disease, most of the treatments on the market now do not seem to work at a satisfactory level, so this treatment sounds very encouraging. However, I was wondering how the patients could not know if their brains were being subjected to deep brain stimulation. It would seem to me that getting a shock to the brain would be something that one would notice, but perhaps the shocks are very mild. I think it would also be interesting to see how this treatment does compare with drugs or if both drugs and DBS at the same time would yield even better results. Also, is it known how this treatment would work on a more widespread scale? Would patients undergoing treatment always have to visit a clinic once a month to have the device operated by doctors, or could patients learn to operate it by themselves? I have also heard of deep brain stimulation as a treatment for depression and other brain surgeries as treatments for obsessive-compulsive disorder. Hopefully, in the future, more direct brain treatments like this one will be as successful in treating other mental illnesses.