How does ADHD work in the brain? What is the role of the prefrontal cortex in ADHD?
ADHD works by impairing executive functions, and it has to do with poor development of the prefrontal cortex and deficits of the neurotransmitters norepinephrine and dopamine. The prefrontal cortex in ADHD brains is less capable of controlling impulses.
Here’s more on how this condition manifests in the brain.
What Does ADHD Look Like in the Brain?
How does ADHD work? The answer begins with the prefrontal cortex. Executive functions are carried out primarily in a part of the brain called the prefrontal cortex (PFC), which is responsible for complex decision-making, logical thinking, impulse control, and emotion regulation. When you’re a child, your prefrontal cortex isn’t fully developed, so you act based on impulse without understanding the consequences of your actions. For example, babies often try to put dangerous items and substances in their mouths because they don’t understand why they shouldn’t. The prefrontal cortex in ADHD brains also works differently.
For most, as you grow older, your PFC develops, and you gain greater control over your executive functions. For instance, you improve your abilities to make plans, think before acting, and use logical reasoning. However, people with ADHD continue to struggle with these skills as they grow older because their PFCs develop differently than the average adult’s.
| Further Exploring the PFC and Other Parts of the ADHD Brain There are two parts of the prefrontal cortex: the medial PFC (mPFC) and the lateral PFC (lPFC). The mPFC is responsible for regulating emotions, forming memories, and self-reflecting. The mPFC includes many executive functions affected by ADHD. The lPFC aids with motor control and sensory processing. These are also qualities many people with ADHD struggle with. Age and ADHD aren’t the only things that can impact the prefrontal cortex. Injury and disease can also alter it, which can lead to personality changes and hindered executive functions. Damage to the prefrontal cortex is associated with schizophrenia, post-traumatic stress disorder, and bipolar disorder. ADHD also affects other areas of the brain beyond the PFC. For example, in ADHD 2.0, Edward Hallowell and John Ratey state that the cerebellum is underdeveloped in people with ADHD. This part of the brain is responsible for things like learning new skills, regulating emotions, and making quick decisions, as well as physical balance and coordination. |
Norepinephrine and Dopamine
ADHD is also linked to a deficit of two important neurotransmitters: norepinephrine and dopamine. Together, these neurotransmitters help you prioritize and focus your attention on the right things. Specifically, norepinephrine helps you filter external stimuli (such as sounds and smells) and internal stimuli (such as thoughts and feelings). Dopamine makes you feel like you’re being rewarded when you finish a goal or task. Without enough of each neurotransmitter, your brain gets easily distracted and has trouble sticking with a single task.
