← 👁️ Neuroscience

👁️ The Pupillary Light Reflex: How Eyes Auto-Adjust to Brightness

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👁️ The Pupillary Light Reflex: How Eyes Auto-Adjust to Brightness

This simulation demonstrates how the pupillary light reflex pathway converts a change in light intensity into a measurable change in pupil diameter through the retina, midbrain, and iris muscles.

🔬 What It Demonstrates

This simulation demonstrates how the pupillary light reflex pathway converts a change in light intensity into a measurable change in pupil diameter through the retina, midbrain, and iris muscles.

🎮 How to Use

Adjust the light intensity and watch how the pupil size responds in real time, and try toggling single-eye illumination to see the consensual reflex in action.

💡 Did You Know?

The pupillary light reflex is so fast and involuntary that it still functions in unconscious patients, which is why it is used as a bedside indicator of brainstem health.