Brain scans have helped researchers understand ADHD, but they cannot currently diagnose it in an individual person. ADHD diagnosis still relies on a careful clinical assessment of development, symptoms and everyday impact.

Research has identified group-level differences associated with ADHD across brain development, function and neurochemistry. The picture is complex, and there is no single brain feature that defines an individual with ADHD.

ADHD presentations describe different patterns of inattentive and hyperactive-impulsive symptoms. They are useful clinical descriptions, but they do not mean everyone with the same presentation will have the same experience.

Time can feel surprisingly unreliable with ADHD. Estimating duration, noticing time passing, preparing for something later and moving between activities can all require more active support.

ADHD can look very different from one person to another. Traits, environments, support, co-occurring conditions and changing life demands all influence how the condition appears in everyday life.

Knowing what needs to be done does not always make doing it straightforward with ADHD. Initiating, sequencing and sustaining action can create difficulty even when the task itself is fully understood.

Working memory helps keep information available while you are using it. With ADHD, something can genuinely matter and still disappear from mind before you have had the chance to act on it.

Executive functions are the mental processes that help us organise and regulate goal-directed behaviour. They can help explain why everyday tasks sometimes become difficult even when you know exactly what needs to happen.

ADHD can involve distractibility in one situation and intense focus in another. Understanding attention as something that must be directed, sustained and shifted helps explain why both can occur.

ADHD can affect far more than the ability to pay attention. Executive functions, working memory, inhibition, motivation and time awareness can all shape how everyday tasks are managed.

The word neurodevelopmental helps explain why ADHD begins during development, even when it is not recognised until adulthood, and why its effects can look different across a person's life.

ADHD is a neurodevelopmental condition that affects more than attention alone. Understanding what ADHD actually is can make familiar patterns in everyday life easier to recognise and describe.