Questions for “Sleep-friendlier lighting is on the way”

a woman looking at a cell phone on a bed in front of a large screen on a dresser. the screen is on and bright white

Most modern indoor lighting and screens use blue LEDs, which emit light wavelengths that confuse the brain’s internal clock. That can make it hard to fall asleep.

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To accompany “Sleep-friendlier lighting is on the way


Before Reading:

1.  How do animals get rid of liquid wastes from their bodies? In humans, what organs help make this happen?

During Reading:

1.  Why are people advised not to watch TV or use digital screens close to bedtime?

2.  What is special about blue wavelengths when it comes to wakefulness or sleepiness?

3.  How does an LED work? How does it create “white” light?

4.  What is melatonin and what role does it play in sleepiness or wakefulness?

5.  What are two ways that people currently can counter the effects of blue light at night, according to the story?

6.  What is a phosphor and how might the new phosphor being developed at the University of Houston help with the light-at-night problem?

7.  What cautions does Mariana Figueiro offer in interpreting the importance of the new LED light?

After Reading:

1.  Based on what you read in this story, when would be the best time of day to use LED-lit devices? What is the worst time to use them? Did the researchers make a compelling enough case for you to consider changing when and how you use LED-lit devices? Explain why or why not.