ADHD: Core Domains
ADHD is officially defined by three core areas: inattention, hyperactivity, and impulsivity. But research increasingly recognises a fourth: emotional dysregulation.
- •Difficulty sustaining attention on tasks or play activities
- •Often seems not to listen when spoken to directly
- •Doesn't follow through on instructions; fails to finish schoolwork or chores
- •Difficulty organising tasks and activities
- •Avoids or is reluctant to engage in tasks requiring sustained mental effort
- •Often loses things necessary for tasks (toys, homework, pencils)
- •Easily distracted by extraneous stimuli (or unrelated thoughts in teens)
- •Forgetful in daily activities
- •Fidgets with hands or feet; squirms in seat
- •Leaves seat when remaining seated is expected
- •Runs about or climbs in situations where inappropriate (restlessness in teens)
- •Unable to play or engage in leisure activities quietly
- •Often "on the go" or acts as if "driven by a motor"
- •Talks excessively
- •Blurts out answers before questions are completed
- •Difficulty waiting their turn
- •Interrupts or intrudes on others
- •Acts without thinking about consequences
- •Makes important decisions on the spur of the moment
- •Intense emotional reactions that seem disproportionate
- •Difficulty calming down once upset
- •Low frustration tolerance
- •Rejection sensitivity - devastated by criticism or perceived rejection
- •Quick to anger, quick to tears
- •Emotions felt intensely and expressed immediately
For a diagnosis, children must show 6 or more symptoms in either or both domains (5 for teens and adults over 17). These symptoms must:
- Be present for at least 6 months
- Be inconsistent with developmental level
- Directly impact social, academic, or occupational functioning
- Have started before age 12 (even if not recognised until later)
- Be present in two or more settings
Emotional symptoms were part of the original ADHD descriptions but were removed from diagnostic criteria in the 1980s. However, research now shows emotional dysregulation is a core feature of ADHD, not just a comorbid issue.
For many families, emotional difficulties - especially rejection sensitive dysphoria (RSD) - cause more daily distress than attention or hyperactivity symptoms.
Learn about RSDThe three presentations
ADHD is diagnosed as one of three presentations depending on which symptoms are most prominent. Presentation can change over time.
Meets criteria for inattention but not hyperactivity-impulsivity. Often called "ADD" (an outdated term). More common in girls and often missed.
Meets criteria for hyperactivity-impulsivity but not inattention. Less common, especially after early childhood.
Meets criteria for both inattention AND hyperactivity-impulsivity. The most commonly diagnosed presentation.
What it looks like in real life
The clinical criteria can feel abstract. Here's how these symptoms often appear at different ages:
| Domain | Child (5-11) | Teen (12-17) | Adult (18+) |
|---|---|---|---|
| Inattention | Starts getting dressed but gets distracted by a toy and forgets to finish | Sits down to do homework but ends up on phone without realising how | Walks into a room and completely forgets why |
| Hyperactivity | Can't sit still at dinner; constantly getting up and moving | Feels internally restless; taps pen constantly; can't relax | Always needs to be doing something; uncomfortable with downtime |
| Impulsivity | Grabs a toy from another child without thinking | Sends an angry text and immediately regrets it | Makes impulsive purchases; says things without filtering |
| Emotional | Complete meltdown when told "no"; inconsolable if a friend doesn't want to play | Devastated by a teacher's correction; replays criticism for days | Perceived slight at work ruins the whole week; avoids feedback situations |
ADHD symptoms are context-dependent. A child might focus intently on video games but struggle to focus on homework. This isn't wilful - it reflects how ADHD affects the ability to direct attention to tasks that aren't intrinsically motivating.
Similarly, symptoms often improve when:
- The activity is novel or interesting
- There's immediate feedback or reward
- The child is one-on-one with an adult
- Stakes are very high (exam day, important event)
This variability can make ADHD harder to recognise - "If they can focus on games, why not homework?" - but it's actually a core feature of the condition.