Brain Network Connectivity May Be Behind ADHD

Connections between three networks in the brain that play a crucial role in attention are weaker in children with attention-deficit hyperactivity disorder (ADHD).

Vinod Menon, PhD, a psychiatry professor at Stanford University School of Medicine, and colleagues used function MRI (fMRI) imaging to examine brain scans of 180 children, half of them with ADHD. Scans were taken when the children were awake. In addition, they were assessed for symptoms of ADHD using standard diagnostic measures.

Each scan was rated based on the level of synchronization between the salience network and two other networks, the default mode and central executive. The former is responsible for directing activities such as daydreaming, while the latter interacts with information in working memory.

Menon and his team had thought that poor coordination between the three regions could be responsible for mental conditions including autism, depression, and schizophrenia.

Children with ADHD had weaker connections between the three networks than children without the condition, the researchers reported in the journal Biological Psychiatry. The difference was large enough that brain scans could distinguish kids who had ADHD from those who did not.

In addition, children that has the weakest connections did the poorest on tests measuring inattentiveness.

Additional research is needed to determine whether fMRIs can also differentiate between the brains of children with ADHD and those with other neurodevelopmental conditions.

Reference

Cai W, et al. Aberrant Cross-Brain Network Interaction in Children With Attention-Deficit/Hyperactivity Disorder and Its Relation to Attention Deficits: A Multisite and Cross-Site Replication Study. Biol Psychiatry. 2015; doi: 10.1016/j.biopsych.2015.10.017.