As of Oct. 3, 2026, MyChart is now your new online health record at Children’s Minnesota. Learn more and activate your account now.
As of Oct. 3, 2026, MyChart is now your new online health record at Children’s Minnesota. Learn more and activate your account now.
Article Translations: (Spanish)
Say: PYOO-puls
Pupils are in charge of how much light goes into your eye. That's why your pupils get larger in the dark (to let more light in) and smaller in the light (to keep some light out). You can use a small flashlight to test how your pupils, or your friend's pupils, change when the amount of light near them changes. It's all in a day's work for the incredible, shrinking, growing pupil.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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Managing your child’s health care is easier with MyChart, your secure online health record at Children’s Minnesota. Set up and activate your Children’s Minnesota MyChart account.
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