Keeping your phone next to your bed
Another key to getting better sleep is not letting outside influencers impair your sleep.
The LED screens of our smartphones, tablets, and laptops, for example, give off what is called blue light, which studies have shown can damage vision and suppress production of melatonin, a hormone that helps regulate the sleep cycle.
Research also suggests that people with lower melatonin levels are more prone to be depressed.
suppress vt. 镇压；隐瞒；压制；止住；禁止
The revolt was suppressed in a matter of hours.
All these movements were suppressed by the warlord government.
A common person would not suppress his real name.