Too much stress can actually rewire the brain, impairing memory and decision making capabilities, increasing anxiety and reducing the ability to regulate mood. Thats because chronic stress causes an increase of certain brain chemicals and hormones, like cortisol, that in large quantities can negatively affect parts of the brain that are essential to memory. Find something you enjoy that helps you relax, like a hobby, reading a book or doing yoga. The brain is resilient if you give it a chance! Sleeping enough is also important. Researchers found that people who sleep less than six hours per night or more than nine hours per night tend to have lower cognitive scores than people who slept between 7.5 8 hours per night.