What is attention deficit hyperactivity disorder?

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Attention deficit hyperactivity disorder (ADHD) is the most common mental condition affecting children and adolescents.

It is an alteration of brain development that affects the maturation process of different areas of the brain. This affects brain activity and function.

Attention Deficit Hyperactivity Disorder explained in first person

This disorder affects 3.4% of the world's population. It is the most common disorder in childhood and adolescence. So within a classroom, in a school class, each teacher may have between 1 and 3 affected children.

It is an established disorder characterised by a lack of self-control with three main symptoms:  

  • Inattention: difficulty in sustaining and directing attention.
  • Hyperactivity: difficulty in controlling movement.  
  • Impulsivity: difficulty in controlling the first response; acting without assessing the consequences. Hyperactivity and impulsivity are symptoms related to each other.

There is another symptom that is not currently considered as a main symptom, but is frequently observable in ADHD, which is difficulty in controlling emotions such as anger, sadness, anxiety or fear and even joy.

Symptoms usually appear before the age of 7, although many times their diagnosis is not made until they reach school age (either primary or secondary), when behavioural difficulties become more evident.  

Although it is a childhood-onset disorder that can improve significantly, it is currently considered chronic, especially in those cases that present severe ADHD. Early diagnosis facilitates the adaptation of the environment and reduces the academic, social and family impact of the disorder.

Types of ADHD

Traditionally, ADHD was classified into three subtypes, based on the prevalence of the symptoms for attention deficit or hyperactivity.    

Currently, this division of ADHD by subtypes has been dismissed; as changing from one subtype to another throughout life has been seen to be common. Over time, the hyperactivity symptoms usually diminish, especially after adolescence, but inattention symptoms usually persist.  

Some people with more intensive attention deficit symptoms can be called people with pure ADD. This subtype is more frequent in girls, and can often go unnoticed and be confused with a delay in maturity.

How many people does it affect?

It affects slightly more men than women in the general population. However, among children or adolescents referred to a mental health care centre, the difference shoots up to 9 boys for every girl attended. This is attributed to the manifestation of the disorder in girls presenting fewer behavioural alterations. Symptoms that girls present tend to be confused with childish and immature behaviour.

Substantiated information by:

Marta Garcia Giral
Montse Vila
Rosa Nicolau

Published: 18 February 2022
Updated: 18 February 2022

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