The ADHD count
ADHD is the restless, novelty-chasing drive that sent children out after food for most of human history, and school hands it a chair and nothing to find. A child built to move through a mixed-age group, playing, watching and gathering its own food, now sits at set work under one adult in a class born the same year. Rough play, the rehearsal for courtship and rivals, gets cut too, and the children whose drive runs strongest, boys most, are the ones counted in the 13.8 percent.
Source: Percentage of Children Who Had Ever Received an ADHD Diagnosis, Centers for Disease Control and Prevention, 29 Oct 2026
The CDC figure counts labels. In household interviews, the share of American children aged 5 to 17 ever diagnosed rose from 9.9 percent in 2019 to 13.8 percent in 2025. Genes do not shift that fast, so the labelling or the setting changed, and the report examines neither.
For most of human history, children past infancy spent the day in a mixed-age group that largely ran itself, learning by playing, watching and joining in, and gathering a considerable share of their own food. School swaps that for a class born the same year, one adult who decides the task, the pace and when anyone may stand, and worksheets graded later. In a room built for stillness, the drive to explore, move and play comes out as fidgeting, drifting and acting on impulse.
How hard that drive pushes runs in families and differs from child to child. Forager children played in one mixed-age group, and sorting children by birth year under one adult turns that spread into a ranking, with the most restless flagged first. A forager could walk to another camp, and a child cannot leave the room.
Where a measurable physical cause exists, such as a brain injury or poisoning, the restlessness is a symptom of it, and in every other child the label names a heritable drive stuck in a chair.
What they say it is
They say
A rising share of children with an ADHD diagnosis means a rising share of children have a disorder.
"the percentage of children and adolescents aged 5-17 years who had ever received a diagnosis of ADHD increased from 9.9% to 13.8%"
Held by the headline and the QuickStats framing, which present a rising diagnosis count as a rising condition.
What it really is
ADHD is the restless, novelty-chasing drive that sent children out after food for most of human history.
Which system wins
Every brain system that could explain this, oldest at the top. The bar is how well each one explains the source.
Oldest firstScore, out of 1
-
500million yrsRestless temperament in a chair
-
500million yrsA body built to move made to sit
-
200million yrsYoungest in the class read as disordered
Why it wins. Restless temperament in a chair explains 3 of the 7 details in the source and sits on standing. It ties on score with Youngest in the class read as disordered (0.42) and leads because Youngest in the class read as disordered only explains who is hit harder, not why it happens.
The 7 details and the scores as a table
- D1 turning point Ever diagnosed with ADHD, ages 5 to 17, rose from 9.9 percent in 2019 to 13.8 percent in 2025.
- D2 The share rose for boys and for girls throughout.
- D3 More boys than girls have a diagnosis.
- D4 Estimates come from household interviews, National Health Interview Survey.
- D5 CDC labels it attention-deficit/hyperactivity disorder.
- D6 Taken for granted: children spend the school day seated in same-age classes.
- D7 The youngest children in a class are diagnosed about 30 percent more often.
| Reading | System | At stake | Details | Distance | Score |
|---|---|---|---|---|---|
| Restless temperament in a chair | M2 | Standing | 3/7 | 3/3 | 0.42 |
| Youngest in the class read as disordered | M4 | Standing | 3/7 | 3/3 | 0.42 |
| A body built to move made to sit | M10 | Standing | 2/7 | 3/3 | 0.39 |
Score = 0.571 x what is at stake (survival 1, reproduction 0.67, standing 0.33) + 0.286 x share of details explained + 0.143 x distance from the camp. Phylogenetic age adds no points; it orders the stack and settles near-ties.
So now what?
- Give the child daily time outdoors in a group of children of different ages who run their own physical play, with no adult directing it: neighbours, older cousins, a street or park group.
- Ask the school for lessons that let children stand, walk and work with their hands, and for permission to get up without asking.
- Hand the child real jobs with a result they can hold the same day: cooking a meal, building something, growing food, running an errand.
If you take psychiatric medication: where no biomarker shows a physical disease, the goal is to come off it. Work on the real cause, most often your situation with other people, at the same time as a slow taper supervised by your doctor. Never stop suddenly: stopping some drugs at once is dangerous.
How do we know?
8 claims, 5 counterpoints
For most of human history food, water and warmth had to be found and gone after, and the brain's seeking circuit made people curious, restless and eager to get them. Every mammal carries the same circuit.
E251 argued, not yet testedE252 tested many timesE397 tested many timesE394 tested many timesE516 seen in animals
In household interviews, the share of US children aged 5 to 17 who had ever received an ADHD diagnosis rose from 9.9 percent in 2019 to 13.8 percent in 2025, for both sexes.
Forager children past infancy spent their days in a mixed-age group, learning by playing, watching and joining in, with much teaching from other children, and even young children gathered a considerable amount of their own food.
EEA-CARE-03 tested many timesE789 argued, not yet testedE716 contestedE788 tested onceE787 tested once
People in mobile forager bands could move to another camp at any time.
E677 argued, not yet testedEEA-SOC-10 contestedE684 tested many times
Boys are diagnosed more often than girls.
Rough play is more common in boys, and in the animals studied it rehearses courtship and sorting standing among rivals.
Forager work was small-group and hands-on, with a visible link between effort and result.
Forager adults moved on foot through the day as a side effect of getting food, with over two hours a day of moderate to vigorous activity.
EEA-SUBS-01 tested many timesE196 tested onceE715 tested once
What cuts against it
Constructed-emotion research finds no consistent brain or body fingerprint for any single emotion and reads so-called emotion regions as body-budgeting regions, which disputes treating seeking as one dedicated circuit. Whether ADHD-linked traits actually paid off in foraging is an ungraded hypothesis: the studies that would show it are not in Cor.
E300 tested many timesE301 argued, not yet testedE304 argued, not yet tested
Late Pleistocene social life was probably more varied than the egalitarian mobile-band model, and movement between camps may not have been a general default.
E756 contestedE686 tested many times
Forager children did less rough-and-tumble play than neighbouring farmer children, and adults did teach, so self-run mixed-age play is not the whole of childhood learning.
Forager activity was only about 15 percent above a desk worker's overall and foragers sat as many hours a day as industrial adults, so the movement gap lies in how and when people moved.
Much of ancestral life lay beyond anyone's control: about half of forager children died before 15, and sickness, with infections prominent, caused most deaths in small-scale populations.
Not in Cor yet
Twin studies put the heritability of ADHD traits at about 70 to 80 percent.
Faraone & Larsson 2019, Genetics of attention deficit hyperactivity disorder, Molecular Psychiatry
Children who are the youngest in their school year are diagnosed with ADHD more often than the oldest.
Layton et al. 2018, Attention deficit-hyperactivity disorder and month of school enrollment, NEJM
Adults who screened positive for ADHD left depleting patches sooner in a foraging task and earned higher reward rates.
Barack et al. 2024, Attention deficits linked with proclivity to explore while foraging, Proc R Soc B
Recess and unstructured play time in US schools fell over recent decades.
Gray 2011, The decline of play and the rise of psychopathology in children and adolescents, American Journal of Play
Boys are diagnosed with ADHD more often because the drive being labelled is tied to male hunting and mate competition.
A forager study linking ADHD-like traits or rough-and-tumble play in boys to hunting success or reproductive success
Grades are Cor's. Every id opens its Cor page.
Sources
- Percentage of Children Who Had Ever Received an ADHD Diagnosis. Centers for Disease Control and Prevention, 29 Oct 2026. The source decoded here.
- Barrett (2017). How Emotions Are Made: The Secret Life of the Brain.
- Barrett et al. (2019). Emotional Expressions Reconsidered: Challenges to Inferring Emotion From Human Facial Movements.
- Bird et al. (2019). Variability in the organization and size of hunter-gatherer groups: Foragers do not live in small-scale societies.
- Boyette (2016). Children's play and culture learning in an egalitarian foraging society.
- Crittenden et al. (2013). Juvenile foraging among the Hadza: Implications for human life history.
- Gurven & Kaplan (2007). Longevity among hunter-gatherers: A cross-cultural examination.
- Kelly (2013). The Lifeways of Hunter-Gatherers: The Foraging Spectrum.
- Konner (2010). The Evolution of Childhood: Relationships, Emotion, Mind.
- Lew-Levy et al. (2017). How do hunter-gatherer children learn subsistence skills? A meta-ethnographic review.
- Lew-Levy et al. (2018). How do hunter-gatherer children learn social and gender norms? A meta-ethnographic review.
- Lew-Levy et al. (2020). Who teaches children to forage? Exploring the primacy of child-to-child teaching among Hadza and BaYaka hunter-gatherers of Tanzania and Congo.
- Lieberman (2021). Exercised: The Science of Physical Activity, Rest and Health.
- Panksepp (1998). Affective Neuroscience: The Foundations of Human and Animal Emotions.
- Panksepp (2011). The basic emotional circuits of mammalian brains: Do animals have affective lives?.
- Panksepp & Biven (2012). The Archaeology of Mind: Neuroevolutionary Origins of Human Emotions.
- Pellegrini & Smith (1998). Physical activity play: The nature and function of a neglected aspect of play.
- Raichlen et al. (2017). Physical activity patterns and biomarkers of cardiovascular disease risk in hunter-gatherers.
- Raichlen et al. (2020). Sitting, Squatting, and the Evolutionary Biology of Human Inactivity.
- Singh & Glowacki (2022). Human social organization during the Late Pleistocene: Beyond the nomadic-egalitarian model.
- van Vugt et al. (2024). Digitally Connected, Evolutionarily Wired: An Evolutionary Mismatch Perspective on Digital Work.
- Volk & Atkinson (2013). Infant and child death in the human environment of evolutionary adaptation.
- Woodburn (1982). Egalitarian societies.