Hello — what this blog is for

This is the short version of what you'll find here — a map of the blog before you dive into the longer, cited explainers. If you want the full conceptual treatment, what contrast sensitivity actually measures is the primer to start with.

What this blog is for

Contrast sensitivity is one of the more useful and less-talked-about measurements in vision science. It asks a different question from the 20/20 eye chart: not how small a letter can you read? but how faint a pattern can you see? — across a whole range of pattern sizes. The result is a curve, not a single number, and the shape of that curve tells you something the eye chart does not.

The posts you'll find here are written to do three things, in order:

1. Explain the science honestly. What contrast sensitivity is, what it measures, what it doesn't, and where the evidence is strong vs. shaky. Each claim is cited where possible. If something is contested — and there are contested corners of this field, particularly around mold and CIRS — we say so out loud and walk through both sides.
2. Make the test more useful. We'll explain what a result means, how to read your curve, why some frequencies dip while others stay normal, and what to do if a result concerns you.
3. Talk about specific conditions. Concussion and post-concussive syndrome, multiple sclerosis, glaucoma, cataract, age-related macular degeneration — each one has its own relationship with contrast sensitivity, and each one gets its own post.

What we won't do

We won't claim this test diagnoses anything. We won't use fear-based language about mold or vision loss. We won't suggest a screening tool replaces a real eye exam or a clinician who knows your case. If a post veers near a clinical recommendation, you'll see the same line repeated: talk to a clinician for medical decisions.

If you came here from the test itself — welcome, and thanks for the curiosity. Start with the primer, or skip to the condition that matters to you: glaucoma, cataract and night driving, multiple sclerosis, or concussion. If you came here from somewhere else, the test is one tab over and free.

That's it. More soon.