Upgrades to your first floor

When you face away from activity, your brain is more likely to produce cortisol and adrenaline, hormones associated with stress and anxiety. So the sofa (or the spot where you sit most) should let you see the door to the room and give you a good view through a window. "Scenes of nature light up pathways in the brain that are rich in endorphins," explains Sternberg.

Cost: Zero
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