ADHD: the hungry brain

20 September 2021

They’re often unhelpfully labelled as problem children or difficult adults. Yet those living with ADHD can learn to manage their symptoms and function well with the right support, writes journalist Julie Penfold.

Attention deficit hyperactivity disorder (ADHD) is a common childhood neuropsychiatric condition characterised by a consistent pattern of disruptive behaviours including inattention, impulsivity and hyperactivity. ADHD is estimated to affect around 3% to 5% of children in the UK (NHS in Greater Manchester, 2018).

The causes of ADHD are not fully understood, but it’s thought there is a strong genetic link as the condition can run in families. A number of environmental risk factors can also predispose a child to ADHD. These include premature birth (before 37 weeks); having a low birthweight; smoking, or drug or alcohol misuse during pregnancy; epilepsy; learning difficulties; acquired brain injury; and adverse maternal mental health. It can also present in adults with mood disorders, a history of substance misuse or those known to the youth or criminal justice system (NICE, 2021; NHS, 2018).

A need for stimulus

‘ADHD is essentially a brain difference that’s best described through the metaphor of the “hungry brain”,’ says Dr Max Davies, consultant paediatrician and co-founder of the charity ADHD UK. ‘It’s a brain that needs constant stimulation to keep it well fed. In the general population, there’s a spectrum from typical to extreme levels of this characteristic. But there’s a point at which […] it becomes a problem in everyday life.’

Symptoms of the condition tend to be noticed early and can appear in children from the age of three to seven. However, these may not be recognised at first, especially if hyperactivity is not present. Changes in a child’s life, such as starting school, can prompt their symptoms to increase in severity.

‘The characteristic of the hungry brain is something that’s present from birth, but there are situations in which the same brain can suddenly cause a problem,’ explains Max. ‘Children may manage reasonably well in pre-school and Reception, but when they move into Year 1 they can suddenly experience problems, and that’s when they present to services. It’s not that their brain has changed – rather, it’s due to the demands of their environment, which are now very difficult for them to cope with. We tend to see a peak of cases at ages seven to nine, a slightly lesser one at ages 11 to 13, and then another peak when they reach university.’

While many children go through phases when they are occasionally restless or inattentive, a child suspected of having ADHD will exhibit consistent behaviour that is different from most of their peers. Their behaviours will occur in two or more settings, such as home, school and social situations. In addition, their symptoms will have been present for at least six months and be clearly interfering with, or reducing the quality of, their academic and social functioning (NICE, 2019).

Diagnosis difficulties

Diagnosis of ADHD in children is made by a paediatrician, specialist consultant psychiatrist or by local child and adolescent mental health services. It’s vitally important that children have a full clinical and psychosocial assessment to consider how their condition affects all aspects of their everyday life to help identify the best treatment approach. Schools can make referrals into diagnostic services, typically via their special educational needs coordinator.

ADHD can vary in intensity, and some children may have only mild or moderate symptoms. For borderline cases, the clinical assessment will consider all aspects of a child’s life to determine what sort of treatment plan is appropriate.

ADHD is diagnosed in between two to 10 times as many males than in females (NICE, 2021) but it’s thought to be under-recognised in girls and women. One of the contributing factors is they are less likely to present with the classic symptoms of ADHD.

‘I’ve found that many girls would not reach criteria for ADHD because they weren’t particularly hyperactive or impulsive,’ says Dr Partha Banerjea, consultant child and adolescent psychiatrist. ‘They would be more likely to daydream and be miles away in their own world. Yet because they wouldn’t be causing any difficulty within the classroom environment, they would often be missed completely. I’d often find they would turn up in my specialist adolescent clinic many years down the line having educationally fallen through the cracks. You would then find that their concentration and attention span is very limited. We used to miss much more cases – I hope we miss fewer now.’

One factor that will not have helped the issue of underdiagnosis in females is the impact of the Covid-19 pandemic. Rates of diagnosis have been affected as a result of services being closed. Max works in the community in Lambeth as part of the team at Evelina London Children’s Hospital and says they have been met with a wave of referrals following the pandemic. ‘I think in the long term there will be an uplift in diagnostic rates, but in the short term there has been a drop.’

Children and young people with mental health conditions such as autism and ADHD have also been adversely affected by the pandemic. ‘It’s had a huge, unrecognised impact and it has been horrendous,’ adds Max. ‘We’re now seeing this trickle down in terms of school exclusions, family break-ups, and the sheer exhaustion and stress this is causing parents.’

Symptoms and comorbidities

As public awareness of ADHD has grown in recent years, it’s reasonable to wonder whether any increase in cases has resulted from people self-labelling as sufferers, or whether clinicians have developed a tendency to overdiagnose. But Max says the opposite is more likely. ‘Over the past few years, we’ve been going from a situation of massive underdiagnosis in the UK to getting it more or less right,’ he says. ‘It might be that we get to a point where professionals start to overdiagnose. It’s always a risk and it’s something we need to be aware of, but we don’t have evidence of that happening at a systematic level in the UK.’

The core symptoms of hyperactivity, inattention and impulsivity can vary in how they present in children (see How might ADHD affect children and young people?). Presentation can be combined, where all three core symptoms are evident, or a child can be predominately hyperactive and impulsive or predominately inattentive only.

‘We also see children that have a lot of tantrums or get very emotional. This can be at any age from three to 13, but it can be harder to tease this out in older children,’ adds Max.

The symptoms of ADHD usually improve with age, but some adults can continue to experience problems after being diagnosed as a child. This can lead to the development of additional problems such as other psychiatric disorders, substance misuse difficulties and problems with employment and relationships (NHS in Greater Manchester, 2018).

Symptoms of ADHD can also overlap with other related disorders. ‘ADHD can be comorbid with anxiety and mood difficulties, especially in adolescence,’ explains Partha. ‘It can also be comorbid with neuropsychiatric conditions such as tics or unusual movements, OCD or neurodevelopmental conditions such as autism spectrum disorder and sensory processing difficulties. What’s most important is a thorough assessment to find out what’s there before treatment is considered.’

Managing the condition

The first step when a child is diagnosed with ADHD is to alter the environment around them. Supporting diagnosed children to increase their understanding of the condition and how behavioural changes can help is an important aspect of the school nurse’s role, especially as behavioural approaches tend to be the first-choice treatment for those with mild to moderate symptoms. Support parents to find out more about the condition and access local peer support services is another way they can help.

School nurses can also advocate brain health advice to children and their families and highlight the importance of sleep, regular exercise and diet. ‘Children, and more so adolescents, can become quite hypoglycaemic if they don’t eat breakfast,’ adds Partha. ‘It can affect their attention 
and concentration levels. They can also become more irritable, moody and anxious and this then makes doing academic work or managing socially even more difficult.’

Teachers' perceptions of ADHD in the classroom

ComRes/ADHD UK’s research on teachers in the UK (2017) found:

Help with learning

School support is essential to help children navigate their way through living with ADHD. ‘If a child’s school is not 100% supportive, their academic progress will falter,’ says Max. ‘Children with ADHD also have much higher rates of exclusion. Almost every outcome is worse in someone with ADHD unless they are supported and their condition is managed appropriately.’

For children in early years settings, a play-based approach can benefit both children and families. ‘Play therapy allows children to address their challenges or barriers in a developmentally appropriate and encouraging way,’ says Rebecca Gilchrist, a paediatric occupational therapist. ‘We can incorporate connections between their brain and sensory systems to find ways to better support regulation. For example, teaching families the right type of structure or movement through play to support a child in getting what they need to feel calmer, more organised and ready to learn.’

The most commonly prescribed treatment for ADHD is methylphenidate. It belongs to a group of stimulant medications and works by increasing activity in the brain, particularly in areas that play a part in controlling attention and behaviour. Methylphenidate can be prescribed for children over the age of five.

‘School nurses can make a huge difference to children and adolescents with ADHD and their families,’ adds Max. ‘Their support will help the young person and their family to function better, and that’s actually what we should be aiming for when we think about managing this condition.’ 


Charity ADHD UK was formed in 2020 to help people with the condition navigate their lives adhduk.co.uk  

NHS advice on symptoms of ADHD bit.ly/NHS_ADHD_advice  

Young Minds insight on ADHD and mental health – advice and support for children and adolescents bit.ly/YoungMinds_ADHD


ADHD UK. (2017) ComRes/ADHD UK research findings on primary and secondary teachers’ experience and understanding of ADHD. See: www.adhduk.co.uk/teachers-and-adhd/ (accessed 28 July 2021).

NHS. (2018) Attention deficit hyperactivity disorder: overview. See: https://www.nhs.uk/conditions/attention-deficit-hyperactivity-disorder-adhd/ (accessed 28 July 2021).

NHS in Greater Manchester. (2018) Delivering effective services for children and young people with ADHD. See: https://www.england.nhs.uk/north-west/wp-content/uploads/sites/48/2019/03/GM-wide-ADHD-guidance.pdf (accessed 28 July 2021).

NICE. (2021) Clinical Knowledge Summaries: attention deficit hyperactivity disorder. See: https://cks.nice.org.uk/topics/attention-deficit-hyperactivity-disorder/ (accessed 28 July 2021).

NICE. (2019) Attention deficit hyperactivity disorder: diagnosis and management. See: https://www.nice.org.uk/guidance/ng87 (accessed 28 July 2021).

Image credit | Shutterstock | Science Photo Library




Subscription Content

Click To Return To Homepage

Only current Unite/CPHVA members or Community Practitioner subscribers can access the Community Practitioner journals archive. Please provide your name and membership/subscriber number below to verify access:

Membership number

If you are not already a member of CPHVA and wish to join please click here to JOIN TODAY

Membership of Unite gives you:

  • legal and industrial support on all workplace issues 
  • professional guidance on clinical and professional issues 
  • online information, training and support 
  • advice and support for all health professionals and health support workers
  • access to our membership communities 
  • CPHVA contribution rate is the Unite contribution rate plus £1.25 per month 

Join here https://www.unitetheunion.org/join-unite/

If you are not a member of Unite/CPHVA but would like to purchase an annual print or digital access subscription, please click here