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Are you sleeping restlessly, forgetting little things, and feeling depressed and lonely? Don't worry. We've all been there. You're probably just stressed out.
Stress isn't always a bad thing. It can be handy for a burst of extra energy and focus, like when you're playing a competitive sport, or have to speak in public.
But when it's continuous, the kind of situation most of us face daily, it actually begins to change your brain. Chronic （长期的） stress, like being overworked or having arguments at home frequently, can affect brain size, its structure, and how it functions, right down to the level of your genes.
As levels of cortisol （皮质醇） rise, electric signals in your hippocampus （海马体）, the part of the brain associated with learning, memories, and stress control, decline. When the hippocampus weakens, so does your ability to control your stress.
That's not all, though. Cortisol can literally cause your brain to get smaller in size. Too much of it results in the shrinking of the part of your brain that regulates behaviors like concentration, decision-making, judgement, and social interaction.
It also leads to fewer new brain cells being made in the hippocampus. This means chronic stress might make it harder for you to learn and remember things, and also set the stage for more serious mental problems, like depression and eventually Alzheimer's disease.
It's not all bad news, though. There are many ways to change what cortisol does to your stressed brain. The most powerful weapons are exercise and getting into deep thoughts, which involves breathing deeply and being aware and focused on your surroundings. Both of these activities decrease your stress and increase the size of the hippocampus, and therefore your memory improves.
So don't feel defeated by the pressures of daily life. Get control of your stress before it takes control of you.