Researchers are learning more and more about brain development and ADHD. Differences in the brain make it difficult for people with ADHD to work on an activity unless they are really interested. This has nothing to do with being lazy or unintelligent.
Learn more about the brains of people with ADHD.
Brain structures with ADHD take longer to develop
Research shows that some parts of the brain tend to be a little smaller or take longer to mature in children who have ADHD. This does not mean that children with ADHD are not intelligent. It means that some parts of your brain develop more slowly.
These developmental delays occur in parts of the brain's self-control system. This includes structures that play an important role in emotional control and a skill called working memory.
In adulthood, these brain structures tend to be similar in size to those of adults without ADHD. However, this does not mean that ADHD disappears after adolescence. ADHD symptoms may change as children grow, but ADHD is a lifelong condition.
Brain networks have trouble making changes
Brain structures need to work together to do things like shift attention or read or write. Different parts of the brain are connected by networks of neurons (brain cells).
Some neural networks take longer to develop or may be less efficient in children with ADHD. An example is “default mode networking.” This plays an important role in resting the brain. In children with ADHD, it takes longer for the brain to “switch off” network activity by default when they need to focus on something.
ADHD also affects other pathways such as the frontoparietal network. This plays a key role in decision making and learning new tasks. (This is why it is often referred to as the “executive control circuit.”) Differences in this and other neural networks may help explain ADHD symptoms such as mind wandering and problems with impulse control.
Brain chemicals may have trouble communicating the message
Brain networks are made of brain cells that pass information from neuron to neuron. To do this, small amounts of chemicals called neurotransmitters are released from the end of a neuron. These chemicals have to cross a small gap called a synapse to reach the end of the next neuron.
ADHD can affect this process in certain ways:
The transmitting neuron may not release enough neurotransmitters.
The receiving neuron may have problems “trapping” the neurotransmitters.
The neurotransmitters may be sucked up too quickly by the transmitting neuron, before a good connection is achieved with the receiving neuron.
For many people with ADHD, treatment can improve these connections. Tapping into people's interests can also help.
Brain researchers are learning more and more about ADHD. But keep in mind that we are not yet at the point where brain scans can be used to diagnose ADHD.