ADHD brains: taking the long way home

This idea that ADHD brains are simply delayed development, not "deviant" development, has been for the most part sort of speculative before, so I'm glad someone has started studying this more thoroughly. Re-posted from Not Exactly Rocket Science:

Attention-deficit hyperactivity disorder is the most common developmental disorder in children, affecting anywhere between 3-5% of the world's school-going population. As the name suggests, kids with ADHD are hyperactive and easily distracted; they are also forgetful and find it difficult to control their own impulses.

While some evidence has suggested that ADHD brains develop in fundamentally different ways to typical ones, other results have argued that they are just the result of a delay in the normal timetable for development.

Now, Philip Shaw, Judith Rapaport and others from the National Institute of Mental Health have found new evidence to support the second theory. When some parts of the brain stick to their normal timetable for development, while others lag behind, ADHD is the result.

The idea isn't new; earlier studies have found that children with ADHD have similar brain activity to slightly younger children without the condition. Rapaport's own group had previously found that the brain's four lobes developed in very much the same way, regardless of whether children had ADHD or not.

But looking at the size of entire lobes is a blunt measure that, at best, provides a rough overview. To get an sharper picture, they used magnetic resonance imaging to measure the brains of 447 children of different ages, often at more than one point in time.

At over 40,000 parts of the brain, they noted the thickness of the child's cerebral cortex, the brain's outer layer, where its most complex functions like memory, language and consciousness are thought to lie. Half of the children had ADHD and using these measurements, Shaw could work out how their cortex differed from typical children as they grew up.

A child grows, their experiences manifest as connections between nerve cells and their cortex thickens. But during adolescence, the developing brain values efficiency over expansion and the cortex starts to thin, as unused connections are mercilessly trimmed. The growth of a child's brain into a teenager's is like the pouring of a block of clay that can then be sculpted away into the refined adult version.

In both groups of children, parts of the cortex peaked in terms of thickness in the same order, with waves of maturity spreading from the edges to the centre. The pattern was the same, but the timing wasn't.

See pictures and more at the original post! 

Reference:Shaw, P., Eckstrand, K., Sharp, W., Blumenthal, J., Lerch, J., Greenstein, D., Clasen, L., Evans, A., Giedd, J., & Rapoport, J. (2007). From the Cover: Attention-deficit/hyperactivity disorder is characterized by a delay in cortical maturation Proceedings of the National Academy of Sciences, 104 (49), 19649-19654 DOI: 10.1073/pnas.0707741104

Opining on the human brain

I found this really article interesting, http://www.slate.com/id/2223835/?GT1=38001

It's a review about a book suggesting a cognitive theory on how baby's brains process the world.

"Gopnik argues that babies are more conscious than adults. Her conclusion is based on the study of how attention and inhibition—the capacity to block out distractions—evolve over the course of development. Adult attention is willful and endogenous. Although it can be captured by external events—we will turn if we hear a loud noise—we also have control over what to think about and what to attend to. By sheer will, we can choose to focus on our left foot, then think about what we had for breakfast, then focus on ... whatever we want. Adults are also blessed, to varying degrees, with the power to ignore distractions, both external and internal, and to stay focused on a single task.

"This is all harder for babies and young children. They are largely at the mercy of the environment. Simple experiments demonstrate that babies are, for the most part, trapped in the here and now, a conclusion supported by the finding that the part of the brain responsible for inhibition and control, the prefrontal cortex, is among the last to develop. Gopnik uses the example of an adult being dumped into the middle of a foreign city, knowing nothing about what's going on, with no goals and plans, constantly turning to see new things, and struggling to make sense of it all. This is what it's like to be a baby—only more so, since even the most stressed adult has countless ways of controlling attention: We can look forward to lunch, imagine how we would describe this trip to friends, and so on. The baby just is. It sounds exhausting, which might explain why infants spend so much of their time sleeping or (like some travelers) fussing.

"For Gopnik, this lack of inhibition and control is a gift. It makes babies and children ideally suited for the task of acquiring information about physical and social reality. When it comes to imagination and learning, their openness to experience makes them "superadults"—not just smart but smarter than we are. She's particularly interested in the power to think about alternate realities, other possible worlds. In several fascinating chapters, she explores how this power is manifested in children's play and in their creation of imaginary companions, plausibly arguing that the capacity to reason about worlds that do not exist is crucial to children's rapid learning about everything from cause-and-effect relationships to human behavior. Gopnik suggests that their neural immaturity gives them greater imaginative powers than adults have: She proclaims, "Children are the R&D department of the human species—the blue-sky guys, the brainstormers. Adults are production and marketing. They [children] think up a million new ideas, mostly useless, and we take the three or four good one and make them real."

It immediately made me jump to the idea that babies are innately ADHD.

I don’t want ADHD people to immediately jump on me and accuse me of calling them immature babies. First, I like the attitude that this brain perspective isn’t necessarily a bad thing. What I AM suggesting, as is Gopnik and LOTS of research on ADD brains, (sources available), is that the ADD brain is more primal, and that by understanding this we non-ADD people can help understand and appreciate ADD thought processes better, and maybe help tap into their gifts (wild and crazy problem-solving, for example).

Gopnik's theory has faults (see page 2 of original article) but I still like the basic concept she’s getting at.

Just an interesting take on how humans develop.

Kenyan study shows possible benefits of ADHD

A study of nomads in Kenya found that nomadic Kenyans with the 7R allele associated with ADHD are overall healthier than their non-ADHD peers. It was also found that men from the same tribe but who are now living sedentary lives are not as healthy as their non-ADHD peers who were sedentary.

Worshiping what's wrong with us

A baby girl was born in India with two faces, and is not only surprisingly healthy, but is being worshiped as a Hindu deity.
Another little girl from India who had been born with multiple limbs is doing well after surgery to remove the extra limbs and repair internal organs.
And then just because my Professor Joan Stevenson has resparked my interest in this subject, I wanted to post a couple of articles about having a "disorder"
The benefits of ADD
Some good characteristics associated with dyslexia
Martin Luther King Jr.'s struggle with depression