How Does ADHD Affect the Brain?

Instructor: Elisha Madison

Elisha has Master's degree in Ancient Celtic History & Mythology, as well as a Bachelor's in Marketing. She has extensive experience creating & teaching curricula in college level education, history, English, business and marketing.

ADHD affects focus and learning, but why do some people have it while others don't? Recently, the medical community has been able to detail the differences. This lesson discusses how ADHD's effects on the brain and what they mean for people who have it.

What is ADHD?

ADHD (Attention Deficit Hyperactivity Disorder) is actually a disorder that affects the brain and affects up to 5% of children presently, making it one of the most common disorders affecting kids today. It causes symptoms such as:

  • Hyperactivity
  • Confusion
  • Attention issues
  • Jumpy and fidgety
  • Interrupting others
  • Moodiness

Up until the last few years, we knew that it was a disorder caused by the brain, but we were not sure why. However with MRI imaging and cat scan technology increasing, the medical field has been able to determine that there are differences between an average brain and one with ADHD, which has helped them to figure out what causes ADHD symptoms and how to help treat them.

Brain Differences

People with ADHD actually have brains that are 3% to 4% smaller than an average brain. This does not affect intelligence but it does affect how the brain works. If the brain is smaller, then the parts of the brain are smaller, in turn. These parts include the frontal lobe and grey matter. The reason why this matters is that the smaller size of certain parts of the brain affects things like impulse control, which comes from the frontal lobe. It also affects concentration and even motor function.

Additionally, other brain differences researchers have found come from the neural pathways. Much like people with heart conditions can have misfirings causing murmurs and other heart issues, brains can do the same. The misfires end up causing issues with concentration, impulses, and inhibitions.

Chemistry is everything. When it comes to a brain that has ADHD, chemistry is also something that is different, then for those without. Uniquely, people with ADHD have less dopamine in their brain. Dopamine actually acts as a carrier of messages to other parts of the brain. So think of it like a truck, a truck takes mail to houses, but if there are less mail trucks than there is less mail, it is slower to be delivered to your door. The mail still gets there, just later. This is what is happening in brains with ADHD. The messages are slower, making it more of a challenge to focus and concentrate.

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