Why and how do ADHD symptoms like inattention, lack of focus, hyperactivity, or impulsivity develop? Why are the emotions more intense and why does this condition often co-exist with depression, anxiety, personality disorders, and sleeping troubles?
For the last few decades, scientists tried to explain these symptoms by looking at how ADHD affects the brain. How is the ADHD brain different from the regular brain? Let’s review in this article some of the most important changes seen in ADHD.
ADHD Brain Vs Regular Brain
- The brain’s structure and volume. There is some evidence that the ADHD brain may be slightly smaller, particularly in the amygdala and hippocampus. These parts of the brain are involved in memory, motivation and regulating emotions. Other areas of the brain – particularly the frontal cortex seem to mature slower in children with ADHD compared with children with ADHD. Although it may take a few years longer, this area of the brain matures to the normal pattern, which may explain why some children outgrow ADHD. Frontal cortex plays essential roles in cognition, attention, control and social behavior. On the other hand, the part of the brain involved in movement seems to develop quicker in those with ADHD, thus making a person more likely to experience fidgeting and hyperactivity. It is important to note that a slightly smaller brain -as seen in ADHD does not affect intelligence.
- The brain’s white and grey matter. The brain contains grey matter which is made up of brain cells and is important in processing information and thinking before acting. White matter of the brain is made up of nerve fibers and is involved in connecting different parts of the brain and complex reactions. The ADHD brain seems to have less gray matter and also changes in the white matter compared with the brain without ADHD.
- The brain’s chemistry. Some key neurochemicals involved in mood, motivation and reward, sleep, memory and appetite like serotonin, dopamine, GABA, norepinephrine and acetylcholine are found to be deficient in some cases of ADHD. Other neurotransmitters like glutamate are found in higher amounts. Excess glutamate is linked with brain inflammation, which is now emerging as a risk factor for ADHD. These neurotransmitter imbalances could explain – at least in part- mood and sleep issues, as well as eating disorders associated with ADHD. On the other hand, drugs and supplements that boost some of these neurotransmitters have a positive impact on the symptoms.
- Brain functions, based on MRIs and other imaging techniques. Thanks to advances in technology, special MRIs can be used to assess brain function. Researchers found that people with ADHD have certain areas more active (hyperactive), while other parts of the brain are less active compared with those without ADHD. Some changes in brain circuits in the ADHD brain are linked with increased functional connectivity which are expressed with symptoms like hyperactivity and restlessness. Other MRI changes seen in individuals with ADHD like reduced blood flow in some parts of the brain may explain changes in executive functioning skills like concentration, attention, focus,organization, social skills, planning and motivation. In addition to functional MRI, other imaging techniques that can evaluate brain changes associated with ADHD include single-photon emission computed tomography (CT), special EEGs and PET scans.
Important lessons to learn
Many children can be impulsive, overactive, or not paying attention to various day-to-day activities. However, those with ADHD really struggle with these symptoms. These brain changes were seen in the volume, structure, chemistry, and functional tests confirm that ADHD is a very real condition that requires treatment. Rather than thinking that a child may be just lazy or unmotivated, now there is proof that the ADHD brain is different. These differences explain changes in behavior, attention, and emotional sensitivity.
The good news is that the brain is extremely “plastic”, it can be re-wired and become healthy again. Stimulant ADHD drugs work in part by increasing dopamine and norepinephrine levels, as well as the blood flow to the brain. Antidepressant and antianxiety drugs work by raising the levels of serotonin, dopamine, norepinephrine, and GABA. In addition to standard treatment, non-drug options can also be used to better manage ADHD and improve brain health. Research suggests that human brains undergo structural reorganization and functional changes in response to training or stimulation. While both physical (physical exercise, yoga) and mental practices (brain exercises) can enhance brain chemistry and function, greater improvements are seen after cognitive training. There are special brain exercises created to improve ADHD symptoms. Consistency is key because the brain needs regular and long-term training. Psychotherapy can also have a positive impact on brain function, and research found that it can increase brain grey matter volume and brain areas involved in emotion regulation. Nutrients like vitamin D and omega 3 may also help balance neurotransmitters, and improve the ADHD brain. It is also important to eliminate factors that have a negative impact on brain health: environmental pollutants, processed foods, and excessive use of electronic devices.
