
What is ADHD?
Attention deficit hyperactivity disorder (abbreviated as ADHD, and sometimes referred to as ADD in the past) is a developmental disorder that begins in early childhood. Children with ADHD may find it hard to concentrate and may become hyperactive, to the point where the condition can interfere with their schooling, friendships, or family life.
Around 1 in every 20 Australians has ADHD. It is more common in boys. More than 3 in 4 children diagnosed with ADHD continue to experience the symptoms into adulthood.
ADHD affects the brain’s executive functioning — the ability to self-regulate and control thoughts, words, actions and emotions.
There are 3 types of ADHD:
- Inattentive means a person is easily distractible or inattentive but isn’t hyperactive or impulsive.
- Hyperactive-impulsive means a person has symptoms of impulsivity and hyperactivity.
- Combined means a person has a mixture of symptoms including hyperactivity, inattention and impulsivity.
What are the symptoms of ADHD?
There are 2 groups of symptoms in ADHD:
Inattentive symptoms
- not paying attention to details, or making careless mistakes in schoolwork
- having difficulty remaining focused in class, conversations or reading
- avoiding tasks that take continuous mental effort (for example, homework)
- not following through on instructions, a tendency to start but not finish tasks
- having difficulty organising tasks, activities, belongings or time
- being easily distracted or daydreaming
- losing things
- not seeming to listen when spoken to
- being forgetful with everyday tasks, such as chores and appointments
Hyperactive-impulsive symptoms
- fidgeting and squirming
- running or climbing in situations where it is inappropriate, leaving their seat in class
- talking non-stop
- interrupting conversations, games or activities or using people’s things without permission
- blurting out an answer before a question has been finished
- having difficulty playing quietly
- having difficulty waiting their turn
- leaving the seat in class or in other situations where sitting is expected
- being constantly in motion, as if ‘driven by a motor’
- struggling to play or do tasks quietly
What causes ADHD?
The exact causes of ADHD are not known, and there is no single cause.
Studies have shown that ADHD symptoms are related to the biology of the brain. It is thought that genetic and environmental factors can interact to cause changes in brain development and function.
- Neurophysiology: People with ADHD have differences in brain anatomy, electrical activity and metabolism.
- Genetics: Research shows that ADHD often runs in families. Researchers are currently working on identifying which genes are involved.
- Drug use during pregnancy: Research has linked ADHD to smoking, alcohol and cocaine use during pregnancy.
- Lead: Some studies have shown that pre-schoolers who were exposed to lead (in certain types of paint or plumbing) had a higher risk of developing ADHD.
- Brain injury: Some children with brain injuries show behaviour that resembles ADHD; however, most children with ADHD have no history of brain injury.
- Lack of early attachment: If a child did not bond with a parent or caregiver as a baby, they can develop inattention and hyperactivity.
- Early childhood trauma: Children who experience trauma in early childhood are more likely to show features consistent with ADHD, but most children with ADHD have not experienced early childhood trauma.
Poor sleep during the night can cause trouble concentrating the following day. It is thought that 1 in 3 children with ADHD might have sleep apnoea (a blocking of the airway during sleep), but it’s not clear whether sleep apnoea is a cause of ADHD. If your child often snores, this might be a symptom of sleep apnoea and may be contributing to the problem.