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The eye has no single megapixel count

Your visual field has a detailed center and a less detailed periphery, and your eyes keep changing where that center falls. Before assigning a camera-like number to vision, you would have to choose a task, viewing conditions, and whether the comparison includes one glance or a sequence of eye movements.

3–7 min

Questions you could explore

  • Would counting light-sensitive cells tell you how much detail someone can actually distinguish?
  • How do eye movements and differences across the retina complicate a camera-style pixel comparison?

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Health and the body

Daylight and the body's clock

Internal daily rhythms respond to outside cues, with light helping coordinate the body's sense of time.

3–5 min

Daylight and the body's clock

Health and the body3–5 minInternal daily rhythms respond to outside cues, with light helping coordinate the body's sense of time.

Health and the body

How vaccines build immune memory

Vaccines make use of recognition and memory, though different vaccine types introduce the relevant information in different ways.

4–5 min

How vaccines build immune memory

Health and the body4–5 minVaccines make use of recognition and memory, though different vaccine types introduce the relevant information in different ways.

Antibiotics and the viruses they cannot treat

Health and the body2–3 minAn antibiotic that helps against certain bacteria has no matching target in the viruses that cause a cold.

The eye has no single megapixel count | Speech Topic | speaking.app