Attention-Deficit/Hyperactivity Disorder (ADHD) is one of the most common psychiatric disorders among school children. Pupils with ADHD often make poorer decisions than their unaffected classmates. Researchers from the University of Zurich now discovered that different learning and decision-making mechanisms are responsible for these behaviors, and localized the underlying impairments in the brain.
Which shirt do we put on in the morning? Do we drive to work or take the train? From which takeaway joint do we want to buy lunch? We make hundreds of different decisions every day. Even if these often only have a minimal impact, it is extremely important for our long-term personal development to make decisions that are as optimal as possible. People with ADHD often find this difficult, however.
They are known to make impulsive decisions, often choosing options which bring a prompt but smaller reward instead of making a choice that yields a greater reward later on down the line. Researchers from the University Clinics for Child and Adolescent Psychiatry, University of Zurich, now reveal that different decision-making processes are responsible for such suboptimal choices and that these take place in the middle of the frontal lobe.
Mathematical models help to understand the decision-making processes
In the study, the decision-making processes in 40 young people with and without ADHD were examined. Lying in a functional magnetic resonance imaging scanner to record the brain activity, the participants played a game where they had to learn which of two images carried more frequent rewards.
In order to understand the impaired mechanisms of participants with ADHD better, learning algorithms which originally stemmed from the field of artificial intelligence were used to evaluate the data. These mathematical models help to understand the precise learning and decision-making mechanisms better.
“We were able to demonstrate that young people with ADHD do not inherently have difficulties in learning new information; instead, they evidently use less differentiated learning patterns, which is presumably why sub-optimal decisions are often made”, says first author Tobias Hauser.
Multimodal imaging affords glimpses inside the brain
In order to study the brain processes that triggered these impairments, the authors used multimodal imaging methods, where the participants were examined using a combined measurement of functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) to record the electrical activity and the blood flow in the brain. It became apparent that participants with ADHD exhibit an altered functioning in the medial prefrontal cortex – a region in the middle of the frontal lobe.
This part of the brain is heavily involved in decision-making processes, especially if you have to choose between several options, and in learning from errors. Although a change in activity in this region was already discovered in other contexts for ADHD, the Zurich researchers were now also able to pinpoint the precise moment of this impairment, which already occurred less than half a second after a feedback, i.e. at a very early stage.
Psychologist Tobias Hauser, who is now researching at the Wellcome Trust Centre for Neuroimaging, University College London, is convinced that the results fundamentally improve our understanding of the mechanisms of impaired decision-making behavior in people with ADHD. The next step will be to study the brain messenger substances. “If our findings are confirmed, they will provide key clues as to how we might be able to design therapeutic interventions in future,” explains Hauser.
Tobias U. Hauser, Reto Iannaccone, Juliane Ball, Christoph Mathys, Daniel Brandeis, Susanne Walitza & Silvia Brem: Role of Medial Prefrontal Cortex in Impaired Decision Making in Juvenile Attention-Deficit/Hyperactivity Disorder, in: JAMA Psychiatry, doi: 10.1001/jamapsychiatry.2014.1093
Dr. Tobias Hauser
University Clinics for Child and Adolescent Psychiatry, University of Zurich, and
Wellcome Trust Centre for Neuroimaging, University College London
Phone: +44 74 749 030 03
Nathalie Huber | Universität Zürich
Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg
Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy