What is ADHD?
ADHD (Attention Deficit Hyperactivity Disorder) is neither a lack of willpower nor a parenting issue. It's a neurodevelopmental disorder — a brain that regulates attention, impulsivity, and energy differently.
Go directly to the test →
ADHD is a neurodevelopmental disorder affecting approximately 5% of children and 3% of adults (HAS, 2024). It manifests through difficulties with attention, hyperactivity, and/or impulsivity. It's not a character trait — it's a different brain functioning, recognized by the WHO and the DSM-5.
En 30 secondes
ADHD is recognized by the scientific community as a neurodevelopmental disorder. It involves dysfunction of brain circuits related to dopamine and norepinephrine, which affects the ability to regulate attention, movement, and impulses.
- 3 presentations: inattentive, hyperactive, or combined
- 5% of children, 3% of adults affected (HAS)
- Strong genetic component — often hereditary
What exactly is attention deficit hyperactivity disorder?
ADHD is a neurodevelopmental disorder that affects the regulation of attention, motor activity, and impulsivity. Described in medical literature since the late 18th century, it is now recognized by the World Health Organization (WHO) and the DSM-5 as a neurobiological disorder — not a discipline or willpower problem.
Specifically, the brain of a person with ADHD shows dysfunction of dopaminergic and noradrenergic circuits, particularly in the prefrontal cortex. Dopamine, a key neurotransmitter for motivation and reward, is poorly regulated. The result: difficulty maintaining attention on tasks deemed unstimulating, constant novelty-seeking, and harder emotional regulation.
ADHD affects approximately 5% of children and 3% of adults according to the French National Authority for Health (HAS, 2024). It is 2 to 3 times more frequently diagnosed in boys than girls during childhood — a gap that equalizes in adulthood (1:1 ratio), partly because female ADHD is often underdiagnosed.
There are three presentations of ADHD, defined by the DSM-5: predominantly inattentive (formerly "ADD"), predominantly hyperactive-impulsive, and combined type. ADHD is often confused with giftedness (HPI) (similar need for stimulation) or autism spectrum disorder (shared social difficulties). In 2026, diagnosis relies on a comprehensive clinical evaluation — there is no blood test or brain scan that can confirm it alone.
- Nature: neurodevelopmental disorder (dopamine, norepinephrine)
- Prevalence: 5% of children, 3% of adults (HAS, 2024)
- Diagnosis: clinical evaluation based on the DSM-5
- Gender: 2-3 boys per girl (children), 1:1 ratio (adults)
8 signs of ADHD in daily life
Click a card to see concrete examples. If you recognize yourself in several of these signs since childhood, with an intensity that impacts your life, it's worth exploring further.
Difficulty sustaining attention
Your brain drifts despite yourself. In meetings, in class, in conversation — your attention slides to something else without you deciding it. It's not a lack of interest, it's a deficit in attention regulation.
Au quotidien
- • You reread the same paragraph 3 times without retaining what you just read
- • In conversation, you mentally drift even when the topic interests you
- • You regularly forget why you walked into a room
Constant restlessness
In children, it's visible: they can't sit still. In adults, hyperactivity often transforms into inner restlessness — a motor running constantly, an inability to rest without feeling guilty.
Au quotidien
- • You bounce your leg, tap the table or fidget with an object without realizing it
- • You feel an internal tension when you have to sit for a long time
- • You always need to be doing something — idleness makes you anxious
Impulsivity
You act before thinking. Not out of malice or disrespect — your brain sends the action before the filter has time to activate. It's a deficit of inhibition, not morality.
Au quotidien
- • You interrupt people without meaning to — and realize too late
- • You make impulsive purchases that you regret the next day
- • You send a message in the heat of the moment and immediately regret it
Chronic procrastination
It's not laziness. The ADHD brain needs a high level of stimulation to trigger action. Boring, abstract, or deadline-free tasks become physically impossible to start — even when you know they're important.
Au quotidien
- • You put off an important project for weeks, then finish it in one night
- • You need the pressure of a deadline to get going
- • You start a thousand things and struggle to finish a single one
Hyperfocus
The ADHD paradox: the person who "can't focus" sometimes becomes hyper-focused for hours — a trait shared with giftedness (HPI). When a topic fascinates you, you dive in so deeply you forget to eat, sleep, or reply to messages.
Au quotidien
- • You start a project at 8 PM and look up at 3 AM
- • You become an expert on a topic in 48 hours, then move on to something else
- • People close to you complain they can't reach you when you're focused
Emotional dysregulation
Your emotions rise fast, strong, and crash abruptly. A minor frustration can trigger disproportionate anger. This dysregulation is often mistaken for anxiety or depression. It's not instability — it's a brain that poorly regulates emotional intensity.
Au quotidien
- • A small unexpected event can ruin your entire day
- • You swing from enthusiasm to frustration in minutes
- • You struggle to handle criticism, even constructive feedback
Chronic disorganization
Forgotten appointments, lost keys, late bills. ADHD affects executive functions — planning, organization, time management. You're not "messy by choice." Your brain struggles to sequence the steps of a task.
Au quotidien
- • You forget appointments even with a calendar
- • Your desk and home are often messy despite your efforts
- • You systematically underestimate the time needed for a task
Time blindness
ADHD distorts time perception. An hour can feel like 10 minutes, or vice versa. This "time blindness" explains chronic lateness — it's not disrespect, it's a brain that doesn't perceive time passing.
Au quotidien
- • You're systematically late, even when you prepare ahead
- • You have no idea how much time has passed when you're absorbed in something
- • Deadlines feel distant... until they're suddenly imminent
Do you recognize yourself in these symptoms?
Our ADHD test gives you a first overview in just a few minutes. Free, confidential, immediate results.
Gratuit · Confidentiel · Resultat immediat
Inattentive vs hyperactive vs combined ADHD
ADHD is not a single disorder. The DSM-5 distinguishes three presentations based on dominant symptoms. Knowing your profile helps better understand your difficulties — and choose the right strategies.
| Inattentive (ADD) | Hyperactive-impulsive | Combined (mixed) | |
|---|---|---|---|
| Main symptom | Difficulty sustaining attention, daydreaming | Motor restlessness, impulsivity | Both combined |
| Typical profile | Quiet, "head in the clouds," often girls/women | Visible, restless, often boys/men | Variable depending on context |
| Diagnosis | Often late (masked by compensation) | Earlier (visible behavior) | Most common in adults |
| Main risk | Silent academic failure, anxiety | Social conflicts, accidents | Exhaustion, burnout |
| Frequency (children) | ~47% of ADHD children | ~36% of ADHD children | ~17% of ADHD children |
| Daily life | Forgetfulness, losing things, daydreaming | Excessive talking, impatience, restlessness | Alternating between distraction and impulsivity |
These proportions are indicative. The profile can evolve with age — hyperactivity often decreases in adolescence while inattention persists.
ADHD in children, teens, and adults
In children, ADHD often manifests from the start of school. Symptoms appear before age 12 according to the DSM-5. The inattentive child "daydreams" in class, loses their belongings, can't follow instructions. The hyperactive child can't sit still, talks constantly, draws attention. The average age of diagnosis is 9-10 years — but many slip through the cracks, especially girls.
In adolescence, motor hyperactivity often diminishes, but impulsivity and inattention persist. Comorbidities are common: over two-thirds of ADHD children have an associated disorder — anxiety, depression, learning disabilities, or autism spectrum disorder (Ameli, 2024). ADHD teens are more vulnerable to risky behaviors and academic dropout.
In adults, nearly one in two childhood ADHD cases retain significant symptoms (Ameli, 2024). Many discover their ADHD late, often in their thirties — sometimes when their child is diagnosed. The adult with ADHD faces specific challenges: chronic procrastination, difficulty maintaining stable employment, relationship problems, and burnout risk from overcompensation. ADHD in women is particularly underdiagnosed: the inattentive profile, less visible, is often mistaken for anxiety or depression.
- Child: symptoms before age 12, average diagnosis at 9-10 years
- Teen: hyperactivity decreases, inattention persists, behavioral risks
- Adult: 1 in 2 retain symptoms, women underdiagnosed
5 myths about ADHD
ADHD is a neurodevelopmental disorder recognized by the WHO and the DSM-5. It involves dysfunction of brain circuits related to dopamine — it's neither a character trait, nor a parenting failure, nor laziness. Telling someone with ADHD to "just try harder" is like telling a nearsighted person to "just look better."
Approximately 3% of adults are affected by ADHD (HAS, 2024). Nearly one in two children with ADHD retain significant symptoms into adulthood. Motor hyperactivity often decreases, but inattention and impulsivity persist. Adult ADHD is simply less visible — and therefore less diagnosed.
Hyperactivity is just one of three presentations of ADHD. The inattentive form (formerly "ADD") represents approximately 47% of cases in children. These individuals aren't restless — they daydream, space out, lose their train of thought. The "H" in ADHD masks this reality, especially in girls and women.
Methylphenidate (Ritalin®, Concerta®) is the first-line treatment for ADHD, prescribed and supervised by specialists. Scientific studies show no risk of dependency at therapeutic doses. On the contrary, untreated ADHD individuals have a higher risk of developing addictions (tobacco, alcohol, substances).
ADHD has a strong genetic and hereditary component. Screens don't cause it. That said, excessive screen exposure can worsen symptoms of inattention and impulsivity in a child who already has ADHD. The confusion comes from the fact that screens capture attention through rapid stimulation — exactly what the ADHD brain craves.
Already 12,847 people have taken this test
Join the thousands who have already taken the test
A free and confidential self-screening. Immediate results with concrete next steps.
Gratuit · Confidentiel · Resultat immediat
Think you might have ADHD? Here are the steps
Your doubt is legitimate. Here's how to move forward concretely, at your own pace, toward a better understanding of your functioning.
Take a first self-screening
Our ADHD test gives you a first overview in just a few minutes. It's free, confidential, and based on the WHO's ASRS scale. It doesn't replace a diagnosis, but it helps you put words to what you experience daily.
Track your difficulties daily
For 2 to 3 weeks, note situations where you recognize the symptoms described above. When it happens, in what context, with what intensity. This journal will be invaluable for the professional who sees you.
Consult an ADHD specialist
Diagnosis requires a psychiatrist, neuropsychologist, or developmental pediatrician specialized in ADHD. The evaluation includes a clinical interview, standardized questionnaires (such as the DIVA-5), and sometimes a neuropsychological assessment. Expect around 3 to 4 sessions.
Explore therapeutic options
ADHD treatment often combines cognitive behavioral therapy (CBT) and, if needed, medication. Methylphenidate is reimbursed at 65% by French social security with a specialist prescription. Organizations like HyperSupers ADHD France also offer support and resources.
Questions frequentes
The only reliable way to confirm ADHD is through a comprehensive clinical evaluation with a specialist (psychiatrist, neuropsychologist). Diagnosis is based on DSM-5 criteria: at least 5 symptoms present since childhood, persisting for more than 6 months, and impacting multiple areas of life. An online self-screening can help identify signs but doesn't replace a professional assessment.
ADD (Attention Deficit Disorder) is the former term for the non-hyperactive form of ADHD. Since the DSM-5, it's called "ADHD predominantly inattentive presentation." In practice, it's the same disorder, but the person is more dreamy than restless. This profile is often underdiagnosed, especially in girls.
ADHD has a strong genetic component. If a parent has ADHD, the probability that their child will too is significantly higher. Environmental factors (prematurity, prenatal tobacco or alcohol exposure, iron deficiency) also play a role, but genetics remains the primary factor.
Yes, this is called double exceptionality. ADHD and giftedness (HPI) can coexist — one doesn't protect against the other. Diagnosis is more complex because symptoms overlap: quick boredom, need for stimulation, rapid thinking. A specialized professional can untangle both profiles.
Make an appointment with a psychiatrist or neuropsychologist specialized in adult ADHD. The evaluation includes an in-depth clinical interview, standardized questionnaires (DIVA-5, ASRS), and sometimes an attention assessment. Expect around 3 to 4 sessions.
An online test like Deep Tests doesn't replace a comprehensive clinical evaluation. However, it provides a reliable first indicator to identify signs of ADHD. Our test is free, confidential, and gives you immediate results with concrete next steps.
You've read the guide. Take action.
Our ADHD test gives you a first overview in just a few minutes. It's the first step toward better understanding your functioning.
Gratuit · Confidentiel · Resultat immediat
Avertissement
This guide is for educational purposes only. It does not replace a medical diagnosis. Only a qualified healthcare professional (psychiatrist, neuropsychologist, developmental pediatrician) can diagnose ADHD after a comprehensive clinical evaluation. If you recognize yourself in these descriptions, we encourage you to consult.
Sources
- HAS — French National Authority for Health, ADHD Recommendations (2024)
- Inserm — Attention Deficit Hyperactivity Disorder (ADHD)
- DSM-5 — Diagnostic and Statistical Manual of Mental Disorders (APA, 2013)
- DIVA Foundation — Diagnostic Interview for ADHD in Adults (DIVA-5)
- Ameli.fr — Understanding ADHD: symptoms, diagnosis, and evolution