Dear Readers,
One of the most fascinating things we’ve learned about ADHD over the past several decades is that it isn’t truly a deficit of attention. In fact, most individuals with ADHD possess an abundance of attentional capacity. The challenge lies in allocating, regulating, and sustaining attention toward the right task at the right time. Rather than lacking attention, people with ADHD often describe feeling flooded by it—too many signals competing at once.
How ADHD Medications Work: Signal vs. Noise
A central effect of ADHD medications, such as methylphenidate and amphetamine-based treatments, is improving the signal-to-noise ratio in the brain. Neurochemically, these medications increase the availability of dopamine and norepinephrine in key circuits of the prefrontal cortex and striatum.
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Dopamine sharpens reward prediction and motivation, helping the brain prioritize what matters.
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Norepinephrine strengthens neural communication by enhancing cortical signal strength while suppressing background “noise.”
Together, they act like a mental “volume knob,” turning down irrelevant chatter and boosting the clarity of the important channel.
Children describe this experience beautifully:
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A 10-year-old told me: “You know all the TVs at Costco that are all on at one time? The meds make me feel like I can turn off all the TVs but one.”
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An 8-year-old explained to his mom: “When I take my medication it makes me feel like the radio station is tuning in and I can hear it clearly.”
These metaphors capture the essence of what the neurochemistry achieves: a cleaner, more focused mental signal.
White Matter Highways: Frontal Lobe Connections in Attention
Attention is not governed by a single brain region, but by networks of white matter tracts that connect the frontal lobe (the “executive” center) to deeper and posterior brain structures. Five major tracts play key roles in attentional control:
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Superior Longitudinal Fasciculus (SLF): Connects frontal and parietal regions, supporting top-down attention and spatial focus.
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Inferior Fronto-Occipital Fasciculus (IFOF): Links frontal lobes with visual areas, facilitating filtering of visual distractions.
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Cingulum Bundle: Connects frontal cortex to limbic regions, regulating emotional salience of stimuli.
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Corpus Callosum (especially anterior regions): Allows coordination of attentional control across hemispheres.
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Uncinate Fasciculus: Bridges frontal and temporal lobes, integrating memory and attention.
Research using diffusion tensor imaging (DTI) has shown differences in these white matter pathways in ADHD, suggesting disrupted connectivity. Medications enhance functional communication across these circuits by optimizing neurochemical balance, making the “highways” more efficient. This helps the frontal lobe guide attention with greater precision and consistency.
From Deficit to Resource
Although the diagnostic term is Attention Deficit Hyperactivity Disorder, it’s increasingly clear that individuals with ADHD possess a powerful attentional resource. The difficulty lies in control—choosing the right channel, staying with it, and not being pulled away by competing inputs.
Treatment, whether through medication, therapy, or behavioral supports, is not about fixing a “deficit.” It’s about empowering people with ADHD to harness their abundant attention—to channel it deliberately, to regulate it effectively, and to use it as the asset it truly is.
Closing Thoughts
When children tell us their attention feels like too many TVs blaring or a radio lost between stations, they remind us of the lived experience behind the neuroscience. ADHD medications, by reducing the noise and strengthening the brain’s networks of attention, allow those with ADHD to use their extraordinary attentional capacity to its fullest.
Far from being defined by a deficit, people with ADHD have a gift of abundant attention. With the right tools, they can learn to direct this gift powerfully—turning potential chaos into clarity.
Warmly,
Dr. Liz Adams
Neuropsychologist
