Only a few decades ago, it was believed that ADHD was something one outgrew during adolescence. However, about half of those diagnosed at a young age carry it into adulthood.
"For many, the cognitive and behavioral difficulties persist, although they come in a slightly different form," says Anne-Kristin Solbakk, professor of neuropsychology at RITMO – Centre for Interdisciplinary Studies in Rhythm, Time, and Motion.
In recent years, there has been a surge of ADHD diagnoses among adults.
"When we in Norway were permitted to medicate adults at the end of the 1990s, there were initially no adults with ADHD in adult psychiatry. Everyone was in child and adolescent psychiatry. Today, ADHD is the dominant cause of referrals in adult psychiatry," says Venke Arntsberg Grane, Head of Research and Leader at the Department of Neuropsychologyat The Helgeland Hospital Trust/Helgelandssykehuset.
A lack of knowledge about ADHD in adults
The research has so far largely been concentrated on ADHD in children and adolescents. It's therefore not surprising that they constitute the age groups we have the most knowledge about.
"In healthcare, we use the knowledge we have about children and to generalize about adults. This is reflected in the formal diagnostic system. The criteria we use to assess symptoms when diagnosing ADHD are still typically child-like behavior," says Grane.
But there can be significant differences in symptoms and their behavioral manifestations in adults compared to children with ADHD.
"Adults do not run around and climb shelves in a psychologist's office," Grane says with a smile.
"For example, adults often struggle to regulate their emotions, are restless and may have difficulties completing an education and maintaining their jobs. Adults with ADHD change jobs more frequently and have a higher risk of injuries and diseases," says Grane.
To address these knowledge gaps, neuropsychology specialists Grane and Solbakk are researching adults with ADHD. Together with fellow researchers, they aim to better understand the disorder and contribute to improved diagnostic methods.
One phenomenon they have been examining is what they call spontaneous mind wandering.
Mind wandering – both an advantage and a disadvantage
Mind wandering is not something that affects people with ADHD exclusively. We all experience, to varying degrees, that our thoughts suddenly, and without control, drift away from what we are doing.
Suddenly you notice you have tuned out of an audiobook or podcast you're listening to, or when driving, you realize you have been driving for several kilometers without focusing on the driving itself.
"Our hypothesis was that those with ADHD are more prone to spontaneous mind wandering than those without ADHD, says Solbakk," who is also a professor at the Department of Psychology at the University of Oslo.
Mind wandering is not necessarily negative. On the contrary, it can be beneficial for our attention to alternate between focusing on external stimuli and a more internal orientation. But in connection with studies or work, for instance, it can be a significant disadvantage.
"Those of us without ADHD likely have a better control over this mind wandering," says Grane.
The researchers have designed experiments in order to document mind wandering. They want to know how significant the differences are between adults without and with ADHD, and whether a test of mind wandering can potentially be incorporated as part of diagnostic tools.
A truly boring task
The experiment may sound very dull: Both ADHD patients and a healthy control group were asked to respond each time they heard a tone through headphones. The task was: Click with one hand if it's a high tone and with the other hand if you hear a low tone.
"The task is very monotonous," says Solbakk.
And that was exactly the point.
"In such a monotonous task, it's natural to lose focus occasionally, for the mind to start wandering."
On their heads, participants wore an EEG cap with 64 electrodes that measure the brain's electrical activity. They had sensors in their palms to register muscle activity, and in front of them, a camera monitored eye movements and pupils. The researchers were able to see how well the task was completed, and they could also examine the connection between brain activity and behavior.
The experiments confirmed the hypothesis of more mind wandering among those with ADHD.
"We observe it at the brain level, but also in task performance. They do not perform the task as well as healthy controls. Moreover, they report more spontaneous mind wandering than the control group," says Solbakk.
"The pattern of brain waves is similar between those with ADHD and the control group, but there is a difference in the strength of the signals," she says.
The researchers emphasize that those with ADHD do not score lower on all types of tests. Therefore, they find it very interesting to see the results of this particular simple and monotonous task.
"We find a significant correlation between brain measurements and task performance. It's not always that we see such clear connections, so mind wandering has been very rewarding to research," says Solbakk.
Working to improve diagnostic tools
It's not the case that a significant amount of mind wandering automatically means the person has ADHD. Other illnesses or brain injuries can have similar effects.
"It's part of our job as researchers to find out which tests and measurements are most sensitive in detecting issues related to ADHD," says Solbakk.
Thus, they need more research and studies before mind wandering tests can potentially be included in the toolbox used for diagnosing ADHD. ADHD cannot be diagnosed with a simple test, like a blood test. It’s a complex disorder that requires a comprehensive battery of measurements.
"We must ensure that the tools we include in these packages can distinguish between those with ADHD and others. Regarding mind wandering, this is further down the line. But the studies we have conducted can be a significant contribution towards achieving that," says Grane.
In the longer term, they also hope to contribute to better and easier lives for those with ADHD.
"We primarily aim to contribute to increased understanding and improved diagnostics for adults and the elderly, but it is also a goal that the methods can be used to develop more treatment options for patients," says Grane.
