How is the ADHD Brain Different from the Normal Brain?

Many people with ADHD experience things differently from those without it. They might struggle to focus, lose track of time easily, or need constant (or less) stimulation. The ADHD brain vs. the normal brain works differently, but can thrive with the proper care and guidance.

Learn how the ADHD brain functions and how it may differ structurally and chemically from a normal brain.

What is the ADHD Brain?

Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental condition affecting how the brain grows and functions. People diagnosed with ADHD struggle to focus and pay attention, and often demonstrate impulsive behavior or act without thinking things through.

While there is no single, definitive feature of the ADHD brain, research suggests differences in structure, function, and neurotransmitter levels. It is one of the most commonly diagnosed childhood brain conditions in the U.S., with about 11% of American children between 3 and 17 being diagnosed at some point [*].

ADHD commonly overlaps with other neurodivergent traits, with 20% to 50% of children with ADHD also meeting the criteria for autism [*]. A similar percentage of children also experience concurrent learning disabilities like dyslexia.

How is the ADHD Brain Different from the Normal Brain?

The ADHD brain differs from the normal brain in size, neurotransmitters, and brain networks. People with ADHD may experience brain growth more slowly or have different activity levels. While the maturation process depends on a child’s developmental stage, experts typically notice the following differences as they age.

Structural differences

Structurally, the ADHD brain presents differences in the regions involved in attention and self-control. The prefrontal cortex is a critical area that influences how well an individual performs tasks and manages a schedule.

The prefrontal cortex may develop more slowly in children with ADHD. This slowed growth can manifest in shorter attention spans.

Individuals with ADHD also have a smaller amount of gray matter in the brain, especially in youth. Parts of the frontal lobes may also have less volume, which can make it harder for a child to plan and focus [*].

Another commonly afflicted brain system is the Default Mode Network (DMN), which becomes active when the mind is at rest. In people with ADHD, the DMN doesn’t “deactivate” efficiently during tasks, which can make the mind wander and be distracting [*]. Because the DMN becomes overactive, a person might become easily distractible or internally preoccupied.

Chemical differences in the brain

People with ADHD also experience chemical differences in the brain. Nerve cells in the brain communicate differently, affecting how a person regulates their emotions, attention, motivation, and mood. 

These nerve cells and chemicals include:

• Dopamine: The ADHD brain experiences impaired dopamine signaling, which can affect how a person feels pleasure and motivation [*]. It’s like a delivery truck being pulled off the road too soon—the packages (the dopamine) don’t get delivered to their destination, and the recipient (the brain) doesn’t receive what it needs. In some cases, the ADHD brain has extra dopamine transporters, which make completing a task less engaging and rewarding.
• Norepinephrine: This brain chemical is responsible for alertness, arousal, and fight-or-flight responses. As part of the brain’s attention circuits, it functions like a volume knob—it’s often set on low, which can make it hard for a person to concentrate [*].
• Serotonin: This chemical regulates mood, emotions, and feelings of calm. Lower serotonin production in people with ADHD can make it more difficult to regulate emotions and trigger mood swings [*]. 

How the ADHD brain thinks and behaves

Different brain structure and chemistry in people with ADHD can influence how they think and behave. These differences don’t just manifest in short attention spans or shifty moods—they impact how a person experiences things and processes information.

For example, the ADHD brain may cause someone to experience emotions more intensely. Even “small” feelings can hit suddenly and severely, causing a person to cry, feel overly frustrated, or express anger inappropriately [*].

Another thinking issue people with ADHD might experience is attention regulation. Because the brain struggles to control direct focus, a person becomes highly distractible, and their minds often wander. In addition, someone with ADHD might hyperfocus and tune out everything else around them.

The ADHD brain also contributes to time blindness, which is the inability to process the passing of time. This issue can make someone chronically late or cause them to lose track of time when focusing on a task. Time blindness can directly affect a person’s executive functioning because they may struggle to plan, organize, and prioritize tasks.

Finally, acting on impulse is a common ADHD brain behavior rooted in its impulse control center (the frontal lobe) [*]. Reduced activity in this area of the brain can make someone with ADHD struggle to delay gratification. In other words, many people with ADHD tend to want to satisfy their desires immediately, regardless of the consequences. They might also struggle to calm down when upset and cannot “just let things go.”

How the ADHD brain processes information differently

Differences in the ADHD brain also influence how a person processes and retains information. Because the ADHD brain has lower working memory capacity, it can affect how well someone retains multi-step instructions [*]. Someone with ADHD might need help from visual cues, such as writing notes in a planner or repeating information out loud.

Information processing can also affect someone’s learning style. Individuals with ADHD have minds that tend to wander, so passive, one-way learning can be tough for them. Most people with ADHD are visual or kinesthetic learners and learn best by seeing or touching something. As such, people with ADHD may learn better through hands-on activities like demonstrations, videos, and interactive displays.

Because they have a low tolerance for boredom, people with ADHD need to be engaged almost constantly. Thus, they might keep switching between tasks to stay stimulated.

Despite the need to be constantly stimulated, some people with ADHD may be hypersensitive to things like background noise, textures in their clothing, or specific smells. These sensory issues can affect someone’s daily life—they might need to wear noise-canceling headphones or take frequent and controlled sensory breaks.

Can the ADHD Brain Be Changed?

ADHD is not “curable” in the traditional sense, but there are ways to make the brain more flexible and adaptable.

The brain is highly neuroplastic, which means it continuously forms new connections as people age. Exposing the brain to cognitive behavioral therapy (CBT) or ADHD coaching can help it adapt to different situations and improve executive functioning.

Medications, especially stimulants, can also help “reshape” the ADHD brain by adjusting neurotransmitter levels closer to a typical range during the time when the medication is in a person's system. Studies have shown that certain ADHD medications can better suppress the DMN and help people with ADHD “tune in” more effectively [*].

Another method for altering the ADHD brain to improve functionality is through therapy. Behavioral therapy and coaching won’t change brain chemicals directly, but they can help individuals navigate ADHD-specific problems more effectively. For example, a therapist might help younger children with ADHD find ways to calm down through deep breathing or mindfulness instead of lashing out.

Many combine these strategies with lifestyle changes—many experts claim that anything good for the brain is good for ADHD. For instance, sticking to a balanced diet with plenty of protein and omega-3 fatty acids can increase neurotransmitter production and dopamine, which can improve focus throughout the day.

Exercise can also significantly positively impact the ADHD brain because physical activity triggers the natural release of dopamine [*]. After just a few minutes of exercise, you might be more alert and less fidgety.

Sleep is another crucial piece of the ADHD puzzle. People with ADHD often struggle with sleep because their minds race all night. Prioritizing good sleep hygiene, such as having a before-bed routine, can improve focus and mood the following day.

The Bottom Line

Remember, the ADHD brain is different. It isn’t defective. However, it can make certain things like focusing and staying on task difficult for children and adults alike

Supporting a child with ADHD? Use our ADHD worksheets to help improve their executive functioning and coping skills.

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