Hey everyone! I’ve been looking into Visual Cortical Hyperexcitability (VCH) as a possible explanation for some of the screen-related discomfort I experience. its the first thing I have found that explains away all of my symptoms and Im getting screened for it soon but If you struggle with eye strain, headaches, brainfog or light sensitivity when using screens, VCH might be worth exploring. Here’s a breakdown of what VCH is.

1. What Is Visual Cortical Hyperexcitability?

VCH basically means that the neurons in the visual cortex (the part of the brain that processes what we see) react more intensely than usual to visual input. Normally, our brain keeps neuron firing balanced, but VCH disrupts this, making neurons “overreact” to certain visual stimuli—like bright screens, high contrast, or even specific color patterns. This overreaction can lead to symptoms like eye strain, headaches, or even brain fog.

2. Common VCH Symptoms with Screens

If you have VCH, you might experience:

  • Visual Discomfort: Screens, especially those with high contrast or brightness, can feel harsh or overwhelming.

  • Headaches and Migraines: Extended screen time can make you more prone to headaches or migraines, especially if you’re already sensitive.

  • Eye Fatigue and Pain: Long sessions on screens may lead to burning, aching, or even sharp pain around your eyes.

  • Brain Fog and Overload: After too much screen exposure, you might feel mentally “foggy” or overloaded, with slower processing and focus.

3. Screen-Specific Triggers for VCH Symptoms

  • Screen Brightness and Glare: Bright, backlit screens can cause strain, especially with too much glare or contrast.

  • Flickering and PWM (Pulse Width Modulation): Many screens use PWM for dimming, which can create a subtle flicker that people with VCH are highly sensitive to.

  • High Contrast and Motion: High contrast visuals (think bright whites next to dark text) or on-screen motion can overstimulate the visual cortex and cause discomfort.

  • Sudden Light Changes: Going from a dark environment to a bright screen or experiencing sudden brightness changes can make symptoms worse.

  • Patterns and Grids: Striped patterns, checkered backgrounds, or even the grid-like structure of text can sometimes trigger discomfort. Complex or repetitive patterns are often harder for a hyperexcitable visual cortex to process smoothly.

    this could be the reason why many of us are sensative.

    lmk what you guys think.

Do please have a read of my post below:
Seagull's Success Story - Ringing the Bell - LEDStrain Forum

I've not heard the term Visual Cortical Hyperexcitability before, but it looks exactly like what I described. I believe the cause is insufficient serotonin / a weak serotonin neuron network whose purpose is to regulate brain activity and prevent regions of the brain becoming over excited.

    madmozg that’s what I’m trying to figure out but it seems like the best options are cognitive or vision therapy basically you can get trained to take stimuli better or medication is the other option

      madmozg
      accommodative lead

      too much feedforward activity because of lack of feedback stimulation

        Seagull I personally doubt it can be a cause. Rather it is more of the side effect. Also, without going too deep into neurotransmitters, I believe they are all interrelated. Coffee, stress, high focus - all scream to me dopamine, but it depletes serotonin. Why not make an experiment with yourself, as you can increase serotonin in variety of ways:

        • 5HTP supplements with B vitamin (I think overall D vitamin is important too in the winter time if you do not live in sunny place)
        • St Johns wart, which presumably does not create serotonin, rather prevents depletion of it.
        • Carbohydrates like semolina pasta with protein of your choise.

        At least these once are popping into my head. But too much serotonin, or increasing serotonin without increasing dopamine, can have other bad effects on you. In any case, if this is a cause, then taking supplement should have improvement in your eye health.

          dev