2019-07-01_Discover

EVERYTHING

WORTH

KNOWING

68 DISCOVERMAGAZINE.COM

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ADHD, OR ATTENTION

DEFICIT HYPERACTIVITY

DISORDER, usually conjures

images of a child bouncing

off the walls, or an adult

who’s constantly distracted.

Symptoms like these are

what first caught physician

Sir Alexander Crichton’s

attention. In his 1798 book

on mental conditions, he

wrote that people who expe-

rienced such symptoms “say

they have the fidgets.”

Eventually, experts would

realize ADHD is much more

than that. At various times

throughout history, experts

believed there was scant

evidence of abnormal activ-

ity in the brain, and instead

considered it a moral defect

or a hyperkinetic reaction

of childhood. It wasn’t until

the 1930s and ’40s that

researchers realized there

was a strong link between

ADHD-like symptoms and

the brain.

Now, although many

mysteries still shroud this

disorder, we know the brain

and how it functions is a cru-

cial factor, and the scope of

symptoms goes well beyond

fidgeting.

When the brain

gets in the way.

BY LACY SCHLEY

ADHD

What’s Going on

in the Brain

Kids and adolescents with

ADHD tend to have about

3 to 4 percent less brain volume

than their neurotypical peers.

Plus, the brain’s outer layer, or

cortex, usually develops more

slowly, lagging behind by about

three years. Even in adulthood,

some regions don’t catch up.

These reductions could explain

some classic ADHD symptoms,

such as difficulty focusing or

fidgeting.

Although these aren’t all the

areas and networks implicated

in the disorder, here are some

key players and how they differ

in ADHD brains.

Prefrontal cortex: Part of

the frontal lobe; seat of

complex decision making,

strategic planning and

working memory (when

you’re holding information

that’s relevant to the task

at hand, like remembering

you already added sugar

while making a cake).

In ADHD brains: Tends

to be thinner in kids,

adolescents and some

adults.

Basal ganglia: Involved mainly

in motor control, some reward-

related emotions and behaviors,

attention and time estimation.

In ADHD brains: Tends to be

smaller, and less active in kids

specifically.

Brain Structures

and Regions

Frontal lobe: Made up

of many substructures;

hub of emotions and

personality; carries out

executive functions like

planning, control and

decision making.

In ADHD brains: Tends

to be less active and

smaller.

Ventral

anterior

cingulate

cortex

Dorsal

anterior

cingulate

cortex

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