For years, people with ADHD have described something that's tricky to measure: that certain lights feel like pressure on the brain, that busy screens fry their focus, that trying to work in a visually cluttered space can trigger an immediate shutdown.
In March 2025, researchers from Yonsei University published a study showing that ADHD may leave detectable patterns not just in the brain, but in the eyes.
Using AI to analyse retinal images from over 600 children, the models identified ADHD with up to 96.9% accuracy (Kim et al., 2025). This study went even further to find that specific features in the retina correlated with performance on visual selective attention tasks - a core area of executive functioning.
This isn’t a fringe finding. It reflects a broader shift in ADHD research: moving our understanding of attention, focus, and overwhelm into real biological systems.
This study adds further weight to the growing evidence that ADHD is a biologically based condition with measurable, observable markers that go beyond behaviour.
Visual processing and the ADHD experience
If you’ve ever had to leave a café because of flickering lights, or rearranged your whole office just to feel a moment of clarity, you’ve felt the role visual environments play in attention.
ADHD isn’t just about being distracted. It’s about how the brain filters, or struggles to filter, incoming sensory information, especially when it’s complex or constantly changing (Brown, 2009).
Past research has shown people with ADHD experience:
- Reduced contrast sensitivity and colour discrimination
- Increased difficulties with eye coordination, such as strabismus
- Higher rates of accommodative lag and hyperopia
- Elevated retinal background noise, thought to be linked to reduced dopamine function (Meier et al., 2022)
The 2025 retinal imaging study stands out because it connects these functional vision differences to microvascular and structural features of the eye. That means it’s not just about the experience, it’s now something we can measure.
Why the retina?
The retina isn’t just part of the eye, it’s part of the brain. It develops from the same embryonic tissue as the central nervous system and gives researchers a way to study attention, sensory processing, and dopamine systems non-invasively (London et al., 2013).
And dopamine, of course, is central to ADHD.
So when researchers examine vessel density, optic disc shape, and visual noise in the retina, they’re not just studying the eye, they’re learning about how attention systems might be functioning.
Executive function through the visual system
One of the most interesting findings from the Yonsei study was the connection between retinal features and visual selective attention: the ability to focus on relevant visual input while ignoring distractions.
This is a key executive function skill, and one that many people with ADHD struggle with every day.
The same retinal features that predicted ADHD also predicted performance on attention tasks.
What this doesn’t mean
We’re not about to start diagnosing ADHD with eye scans in GP clinics. This is early-stage research, not a finished diagnostic tool. But it is a significant step toward understanding ADHD more fully.
It doesn’t replace behavioural assessments or lived experience. What it does is challenge how we think about where ADHD shows up in the body, and reinforces what many people already know in their bones:
ADHD is a complex condition that affects how you take in, process and respond to the world around you.
The future of ADHD understanding
As ADHD research expands beyond just the brain’s executive control centre, we’re beginning to see the role of systems like:
- sensory regulation
- inflammation
- vascular function; and
- neural "noise".
This broader view explains why environment matters so much!
This opens up new areas for action:
- Designing more supportive classrooms and workplaces (Martin et al., 2020)
- Providing strategies for visual and sensory regulation (Ashinoff & Abu-Akel, 2021)
- Validating how ADHDers experience visual overwhelm and distraction
And it raises useful questions:
- Could retinal data help us tailor ADHD support more precisely?
- Are we integrating visual and sensory profiles into our support strategies as well as we could?
Bottom line
If you’ve ever felt like your eyes were working against you when trying to focus, you’re not imagining it. Visual systems play a huge role in attention, and ADHD is increasingly understood as a condition that affects multiple, connected systems.
The retina just happens to be the easiest one to see.