Adhd – a controversial diagnosis

What is the difference between a spontaneous personality and a neuropsychiatric disability? Although the lines are difficult to draw, this does not prevent researchers at Karolinska Institutet from trying to improve the lives of people diagnosed with ADHD.

Professor Sven Bölte, Head of the KIND unit. Credit: Stefan Zimmerman.

Text: Ola Danielsson, first published in Swedish in Medicinsk Vetenskap, no.1, 2011

"Uh-oh, why did I do that?!" We all know how annoying it can be to lose control for a moment, to act without thinking or, quite simply, not to be able to concentrate on what we are doing.

For around 3% of the population these moments occur so frequently that they are classified as having a disability - ADHD. Attention deficit hyperactivity disorder, to give it its full name, roughly means problems with attentiveness and overactivity. The symptoms include difficulty with controlling impulses and remaining attentive. The result is a lack of self-control that makes social interaction, learning and decision-making harder.

"Serious problems with attentiveness and inhibition of behaviour have been recorded for a long time now, albeit with different names," says Sven Bölte, professor of child and adolescence psychiatric science and head of the Center of Neurodevelopmental Disorders (KIND) at Karolinska Institutet. "There are few psychiatric disorders that start in childhood that have been studied so extensively."

Hard to sustain motivation

As far back as the end of the 18th century, a Scottish doctor described how some children seemed to lack the ability to focus on one thing constantly for a long period of time. He also pointed out that it was hardly surprising that these children had problems at school. Concentrating on dry Latin grammar was hard for everyone - for these children it was impossible.

lisa thorell
Lisa Thorell, credit: Ulf Sirborn.

Lisa Thorell is an associate professor in psychology and researches ADHD in pre-school children. She explains that ADHD can take many forms, as the core symptoms - inattentiveness, impulsiveness and hyperactivity - play an important role in other, more complex capabilities. These include motivation, the psychological drive needed for action.

"Children with ADHD often cause considerable frustration as they just don't seem to care about following instructions," says Thorell. "But it's important to understand that they may not be able to do so as other impulses disrupt their motivation."

Identifying and helping children early

Through her research, Thorell is endeavouring to find a way to identify and help children with ADHD-like problems as early as possible. While some degree of hyperactivity and difficulty with concentrating is completely normal in pre-school children, some children need additional support and training if they are to avoid being caught in a vicious circle.

"There isn't a clear line between ADHD and normal development, and our research aims to identify children in the risk zone rather than necessarily make a formal diagnosis," says Thorell. "The important thing is to find ways of helping individual children in their everyday lives."

Creativity, fearlessness and drive are positive attributes that also go hand-in-hand with ADHD. Thorell is determined to find strengths to build on rather than to focus solely on weaknesses.

"Children with ADHD are often forthcoming, social and highly creative," she says. "If their energy can be channelled in the right direction they can achieve a huge amount."

Unfortunately this particular disorder is often viewed as a recipe for trouble, be it in the school playground, at work or in the pub. Many people with ADHD speak of a childhood where they felt different, got caught up in conflict and were frozen out. Many studies have shown that ADHD is associated with problems, not only at school but also when it comes to holding down a job, being at risk of alcohol and substance abuse as well as criminal behaviour, and involvement in traffic accidents.

The children monitored by Thorell since they were pre-school age are now 17 and 18 years old. A follow-up is currently being compiled and will show, among other things, how they cope with the additional responsibilities that come with adult life.

"We can see that people with ADHD find it harder to do things that have a delayed reward," says Thorell. "Instead, they'd rather do things that have an immediate reward, such as playing computer games instead of revising for a maths test the following day."

Causes of ADHD

The causes of ADHD and similar problems have always been controversial. In the 1970s there was a firm belief that the family environment was significant, where a child's upbringing and domestic relationships played an important role. However, research has shown that the fundamental causes are biological, a belief that is supported by strong hereditary factors. The genes that have been shown to be linked with ADHD are involved in signal transmission with the signal substance dopamine in the brain, especially the front part of the brain, where planning and decision-making are controlled.

"The brain's reward system works differently with ADHD," says Bölte. "It seems as though short-term rewards are given higher priority than rewards that involve a wait."

Some of the information about ADHD's basis in the brain has been acquired in a round-about way, by investigating how the medicines that are effective for ADHD actually work. The first of these was discovered back in 1937 when a doctor used an amphetamine to try to alleviate a form of severe headache in children with serious behavioural disorders. The headaches remained, but some of the children behaved better at school, and the vast majority became calmer without losing interest in the world around them.

Medicines and treatment

We now know that amphetamines affect the signal substances in the brain (primarily dopamine and noradrenaline) and that, paradoxically, this leads to the stimulation of inhibitory processes. The brain becomes more alert to curbing its own impulses.

Many studies have confirmed that medicines that stimulate the central nervous system (amphetamines or methylphenidate) work well on attentiveness, impulse control, planning ability, reaction time, short-term memory, academic performance and learning ability.

"The medication doesn't offer a cure, but it does have a major impact on most patients," says Bölte. "However, we don't know enough about what it is that determines how each individual will react. There are probably genetic and neurobiological differences that we aren't aware of."

Medication is prescribed only as a complement to other approaches. The largest international study of different treatments, MTA - multimodal treatment study of ADHD, shows that ADHD symptoms respond best to combined treatment with medication and psychosocial interventions, such as parental education and training in social skills.

"We need more research into what works best over the long term," says Bölte. "The aim is to develop individual treatment plans."

Training the working memory

One piece of the ADHD-brain puzzle is a failing working memory, in other words, the area of the memory that stores information in the short term. Without a working memory we cannot remember what we are doing at the moment and lose focus. Torkel Klingberg, a memory researcher at the Department of Neuroscience, has developed a computer game to train the working memory that has been shown to work well on schoolchildren with ADHD. Lisa Thorell has also tested this approach on pre-school children. Improvements in working memory are evident, for example, from the fact that children get better at doing several things consecutively without getting stuck on the first thing or skipping through to the last. The results have been so good that the game has been launched as a useable method at preschool too. However, carrying out the training can be tricky.

"We see improvements in those children who do the training, in their cognitive ability and behaviour as perceived by parents and teachers," says Thorell. "The problem is that it's hard to get the children who need it most to actually apply themselves for the required amount of time."

The mental restlessness that characterises ADHD is reflected in a measurable way in the brain's activity. A new form of treatment that will perhaps be tested by KIND in the future uses this and builds on what is known as neurofeedback. The aim is to practise achieving a mental state of relaxation and focus at the same time. In practical terms this may mean that children watch their favourite television programme with electrodes on their head. When their brainwaves indicate that they are getting increasingly restless, the television sound is turned off until the child calms down again.

"It might sound like hocus pocus, but it actually works quite well," says Bölte, though the method is still at the experimental stage.

Genetic and environmental factors

The strong genetic factor and neurobiological basis mean that there are no good ways of preventing ADHD. It is a disability that people are born with and are likely to have for life.

"However, the psychosocial environment has a major impact on the extent of the disability," says Bölte. "Most children with ADHD tend not to have just one diagnosis, but generally two or three. These might relate to additional problems, such as behavioural disorders, that can be limited through behavioural therapy at an early stage."

Henrik Larsson, credit: Ulf Sirborn.

Henrik Larsson, a researcher at the Department of Medical Epidemiology and Biostatistics, is trying to determine which genetic and environmental factors affect the risk of developing ADHD. This involves analysing information from the Swedish Twin Registry and other big population registers. It has been suspected that the risk of ADHD increases if the mother smokes during pregnancy. However, new research has shown that this is not the case.

"New results, that need to be confirmed by more studies, indicate that the link between a mother's smoking and a child's ADHD is down to a common underlying factor and not the smoking per se," says Larsson. "It looks as though there are genetic factors that increase the risk of both maternal smoking and ADHD in the child."

Larsson is trying to find out whether the same applies for other factors that are associated with a higher risk of ADHD, such as low birthweight. The same goes for social factors such as criminal behaviour and alcohol and substance abuse in the family. He is also looking into the interplay between genetic and environmental factors, and how this can sometimes result in vicious circles.

"Parents not only contribute genes but also have an impact on a childs environment in the form of upbringing and the home environment," says Larsson. "But parents often struggle with similar disabilities, which means that they may find it extra hard to deal with their child's problems. Children also affect their upbringing in that their behaviour triggers reactions from their parents. It's important to be aware of this complexity when putting together support for parents."

Some people feel that ADHD is not a proper illness - after all, lots of us sometimes find it hard to concentrate and act without thinking. So what is the difference between "normal variation" and a neuropsychiatric disability? Larsson believes that it all comes down to degrees. His research results support the view that there is no real line that can be drawn between people with the diagnosis and those who are considered normal.

"Poor concentration and hyperactivity can lead to problems irrespective of whether they are big enough to warrant a diagnosis of ADHD," he says. "The diagnosis is one way of identifying those who have the greatest problems."

Sven Bölte is thinking along the same lines and feels that the focus of research is moving away from diagnosis and the "either-or" approach, and instead towards studying the significance of a gradual impairment of various cognitive functions. However, this does not mean that an ADHD diagnosis is not important.

"The real issue is whether the problems are so great that help is needed," says Bölte. "In this kind of situation, a diagnosis can be important as it provides an explanation for the problem that the person is struggling with. It acts as a kind of passport to the help that is available."

Adults with ADHD

We used to think that people grow out of ADHD, though this has now been completely disproved, and ADHD is found in 2-4% of the adult population. Bölte believes that this is a field where there is a lack of knowledge in many areas.

"Adult psychiatry is 10-20 years behind in general, even though there are more and more skilled pioneers," he says. "We need far more research and knowledge when it comes to ADHD in adults."

Portrait of Susanne Bejerot.

Susanne Bejerot, an associate professor at the Department of Clinical Neuroscience, helped to set up one of the first clinics for the investigation and treatment of ADHD in adults in Sweden. Given that patients were carefully registered and assessed with research in mind from the very outset, there is now a valuable bank of material to draw on when studying ADHD in adults.

One common denominator for these patients is that they were not diagnosed with ADHD until adulthood, although most had dealings with a child psychiatrist when growing up.

"There was, by and large, no help for people who were children in the 1980s or before," says Bejerot. "We've really dragged our heels in Sweden when it comes to seeing that a disability could be involved."

"Another lesson is that adult symptoms are different to those in children. The physical hyperactivity tones down with age and the symptoms become more subtle, manifesting as an inner restlessness and a greater sensitivity to stress."

Her research shows that motor problems are common during childhood. Motor function disorders are one of the first signs that a child is developing differently - a clumsiness that Bejerot has shown to increase the risk of being bullied later on.

Many adults with ADHD also have other psychiatric diagnoses, such as borderline personality disorder, social phobia, depression and autism spectrum disorders. Bejerot believes that there is a "diagnostic mishmash" where different disorders can easily be mixed up or have overlapping descriptions.

Social phobia

She is currently investigating social phobia in people with ADHD, and believes that it is probably not more common in people with ADHD, even though they are often diagnosed as social phobics.

"Someone with social phobia will give something a lot of thought before acting," she says, "whereas a person with ADHD is impulsive and does quite the opposite. Over the years this can lead to the development of a kind of social anxiety, but this isn't proper social phobia."

ADHD can aggravate other psychiatric conditions. For example, researcher Eleonore Rydén has shown in her thesis that the bouts of depression that go with bipolar disorder are closer together in patients who also have ADHD. A quarter of the patients monitored by Susanne Bejerot have, at some point, attempted to commit suicide, something that she feels is down to an unfortunate combination of depression, impulsiveness and, sometimes, alcohol and substance abuse.

Bejerot's study is the longest long-term follow-up of drug therapy in adults with ADHD to date. The results show that half of the patients were still in treatment after two years, and that feared side-effects such as developing tolerance to the drug and high blood pressure did not occur, although heart rate did increase.

"It's comforting to know that there are few side-effects and that they are mild," says Bejerot. "The patients who gave up the treatment did so for other reasons."

More people are diagnosed with ADHD

The number of new ADHD diagnoses in Sweden has increased significantly in recent years. Bejerot feels that there has been an explosion, with huge pressure on adult clinics. One explanation is that more cases have been identified as awareness of the disability has increased in psychiatry and society in general, especially when it comes to ADHD in adults.

"I also think that society has become less accepting of people with neuropsychiatric disabilities," she says. "Which means that problems that wouldn't otherwise get noticed get bigger."

Bejerot feels that more research is needed into the causes and treatments that are most effective. But, as she points out, the fact remains that ADHD cannot be cured.

"ADHD is something you are, not something you have," she says. "The only way forward is to create a society where there is room for people with disabilities. It could well be that every workplace will have to have one or two jobs that are designed specifically for people with disabilities. Society in general must take far greater responsibility."

Symptoms of ADHD


This can take the form of concentration problems, carelessness, forgetfulness and distractibility. Many people with ADHD get bored quickly and find it hard to complete things that they are not hugely interested in.


This can manifest as strong and hard-to-control emotional reactions, limited ability to listen to others and problems with handling unstructured situations that require reflection and consideration. In some people impulsiveness can also lead to motor clumsiness.


This is about problems with controlling the level of activity, and it can be either too low or too high. Problems with winding down and sitting still can be followed by extreme passivity and fatigue. While hyperactivity in children is often physical, it can take the form of restlessness and sleeping problems in adults.

Symptoms vary

Some people with ADHD have just one of the core symptoms, while others have several.